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[123.243.199.74]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2ad74f5dd7asm86543625ad.28.2026.02.23.00.22.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Feb 2026 00:22:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1771834927; x=1772439727; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=jL1s5SV3cubFpJlsGLlbrnPoja1OfqVMQ1g/z28whqY=; b=t0z1Rncl4VHQmCds3qTsei37svBaKh95AlT0eTTSXKtRmuWxVcA5ZMZMgM/19EqK0E F9htgvhNofuCA8pYKIBORzf5s2NwkdKVRZYQtYY7y/9i7UnLmXfYmBxFgp3EMeLZlvE0 tS43/6rCjyroQgBk+qImvhNHV5zHQGPbinngB3pFnZSPFKqlrUA2Cl/bSIcSSrcG74Nb iX7D5C2+nA/YKs+Wn6BlzxMnfOmZjLtqDn6sOe3a7gnoMQCySzP8RZPmkCwHnA2XsHmX oTYwWb8H5aqfGjDs9FR+90SgXhPW4wtXvVwVqlfM/wqwbMIC+/Uq4NibubkMUmU8TWPp iWDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771834927; x=1772439727; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=jL1s5SV3cubFpJlsGLlbrnPoja1OfqVMQ1g/z28whqY=; b=pcF9X4ddc7Tx1Xtz2QclRUS8io4/23xcCJKVUJ4r/rgma2p1aXazLECBtynM/fvJ4l xemFrdrzB+SdyzBHsuRcY6fyKwZwF+IQDL93ukGo4wAVNi65o6CUWdLw3HfX0jtLsUcm E6SNpMKBA8ecvpSR3nBjlIcR3+7mIHa3szrbkl1/XxGgOUs/ERC+muoCQ8/qtAH27yEl APTPruwpoBZnWpeVYkg/at3mLxbrkiV/D3hEagEZYWKpuSz4/RzLSv0Kbz3KTz27Xb9P tyyJgDDOr4K6EPHIUFg4p87p3sV/Q+J3ThP7aGlyFh4+rTacs0o+3B5g58mchB0Hf8aP L68A== X-Gm-Message-State: AOJu0YyCeDHHTkdclQgi4JswP+rNY43A/0oO3eiP03o5Yha8g8lKFU+q xR/O42Hi/4FrFceyMNyEdv3ROyDQOt5zyHkkk39YQDsR+cv3Eh9LBxyYbqs9YLUgDxvjSHK96Az 0vHhUgw38EQ== X-Gm-Gg: ATEYQzwRqCPuqMqDeJf1nHLh6XGD6SGqY0ZMs+3bBjGiRrWhTI7b6e9ZLpjcYZhzR3Q kUUAnwQnjfqqW+WkoHuxAgeUB+TIn8YrdLBHU3VEo2W9qTs4Lvyve3ronGRvwcRceRl54fHmB0k ptwr3r5MTmg6E80s+N2Yap01T8KvFSDps3z7a3nRhefjTcy7JrwITIkUMIPai+M35/5zyeB8fot goZKUCrGKHvl7BGy0CBtIyHeYOmWjsY1b1pkR1kop18Uudo+ZxUVgnUoyBQksjDL8WG6ckRVLzg tPnlqKBEPt49ZgPUFBvgxPkDVlw9X3ngt3bFLqAC4gip/njuwGe+miypaX5Lv2fA6DQpRJ26IEO dMgl1myCykh9wjRyBPqULwlJtrRENBv1HP6SjZR4r8EhdV2qaEnAyBknSnWSb4TpWYJe5TrzusQ 8Tnbqs8NS83GJo9JuM5jFtWxXMfavHcBxrQB2GJE79dlqkeE4wxsPezxx3G/9l+YDMBg== X-Received: by 2002:a17:902:d549:b0:2a0:e5cd:80a1 with SMTP id d9443c01a7336-2ad74537235mr75974185ad.41.1771834927286; Mon, 23 Feb 2026 00:22:07 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Cc: max.chou@sifive.com, chao.liu.zevorn@gmail.com Subject: [PATCH v5 1/9] fpu/softfloat: Refactor IEEE format NaN classification to share code Date: Mon, 23 Feb 2026 19:21:46 +1100 Message-ID: <20260223082154.5623-2-richard.henderson@linaro.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260223082154.5623-1-richard.henderson@linaro.org> References: <20260223082154.5623-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::643; envelope-from=richard.henderson@linaro.org; helo=mail-pl1-x643.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1771834945852154100 Content-Type: text/plain; charset="utf-8" From: Max Chou The floatN_is_[quiet|signaling]_nan functions for following formats (float16, bfloat16, float32, float64, float128) contain duplicated logic that should be shared. This commit introduces [float16|bfloat16|float32|float64|float128]_nan_is_snan that determine if a NaN is signaling. Suggested-by: Richard Henderson Signed-off-by: Max Chou Reviewed-by: Richard Henderson Reviewed-by: Chao Liu Signed-off-by: Richard Henderson Message-ID: <20260204051756.667397-3-max.chou@sifive.com> --- fpu/softfloat-specialize.c.inc | 192 ++++++++++++++------------------- 1 file changed, 80 insertions(+), 112 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index ba4fa08b7b..7d2515c1fa 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -226,6 +226,19 @@ floatx80 floatx80_default_inf(bool zSign, float_status= *status) return packFloatx80(zSign, 0x7fff, z ? 0 : (1ULL << 63)); } =20 +/*------------------------------------------------------------------------= ---- +| Determine if a float16 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float16_nan_is_snan(float16 a, float_status *status) +{ + if (no_signaling_nans(status)) { + return false; + } + bool frac_msb_is_one =3D (a >> 9) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); +} + /*------------------------------------------------------------------------= ---- | Returns 1 if the half-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. @@ -233,36 +246,7 @@ floatx80 floatx80_default_inf(bool zSign, float_status= *status) =20 bool float16_is_quiet_nan(float16 a_, float_status *status) { - if (no_signaling_nans(status)) { - return float16_is_any_nan(a_); - } else { - uint16_t a =3D float16_val(a_); - if (snan_bit_is_one(status)) { - return (((a >> 9) & 0x3F) =3D=3D 0x3E) && (a & 0x1FF); - } else { - - return ((a >> 9) & 0x3F) =3D=3D 0x3F; - } - } -} - -/*------------------------------------------------------------------------= ---- -| Returns 1 if the bfloat16 value `a' is a quiet -| NaN; otherwise returns 0. -*-------------------------------------------------------------------------= ---*/ - -bool bfloat16_is_quiet_nan(bfloat16 a_, float_status *status) -{ - if (no_signaling_nans(status)) { - return bfloat16_is_any_nan(a_); - } else { - uint16_t a =3D a_; - if (snan_bit_is_one(status)) { - return (((a >> 6) & 0x1FF) =3D=3D 0x1FE) && (a & 0x3F); - } else { - return ((a >> 6) & 0x1FF) =3D=3D 0x1FF; - } - } + return float16_is_any_nan(a_) && !float16_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -272,35 +256,51 @@ bool bfloat16_is_quiet_nan(bfloat16 a_, float_status = *status) =20 bool float16_is_signaling_nan(float16 a_, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - uint16_t a =3D float16_val(a_); - if (snan_bit_is_one(status)) { - return ((a >> 9) & 0x3F) =3D=3D 0x3F; - } else { - return (((a >> 9) & 0x3F) =3D=3D 0x3E) && (a & 0x1FF); - } - } + return float16_is_any_nan(a_) && float16_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- -| Returns 1 if the bfloat16 value `a' is a signaling -| NaN; otherwise returns 0. +| Determine if a bfloat16 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool bfloat16_nan_is_snan(bfloat16 a, float_status *status) +{ + if (no_signaling_nans(status)) { + return false; + } + bool frac_msb_is_one =3D (a >> 6) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); +} + +/*------------------------------------------------------------------------= ---- +| Returns 1 if the bfloat16 value `a' is a quiet NaN; otherwise returns 0. +*-------------------------------------------------------------------------= ---*/ + +bool bfloat16_is_quiet_nan(bfloat16 a_, float_status *status) +{ + return bfloat16_is_any_nan(a_) && !bfloat16_nan_is_snan(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Returns 1 if the bfloat16 value `a' is a signaling NaN; otherwise return= s 0. *-------------------------------------------------------------------------= ---*/ =20 bool bfloat16_is_signaling_nan(bfloat16 a_, float_status *status) +{ + return bfloat16_is_any_nan(a_) && bfloat16_nan_is_snan(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Determine if a float32 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float32_nan_is_snan(float32 a, float_status *status) { if (no_signaling_nans(status)) { - return 0; - } else { - uint16_t a =3D a_; - if (snan_bit_is_one(status)) { - return ((a >> 6) & 0x1FF) =3D=3D 0x1FF; - } else { - return (((a >> 6) & 0x1FF) =3D=3D 0x1FE) && (a & 0x3F); - } + return false; } + bool frac_msb_is_one =3D (a >> 22) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -310,16 +310,7 @@ bool bfloat16_is_signaling_nan(bfloat16 a_, float_stat= us *status) =20 bool float32_is_quiet_nan(float32 a_, float_status *status) { - if (no_signaling_nans(status)) { - return float32_is_any_nan(a_); - } else { - uint32_t a =3D float32_val(a_); - if (snan_bit_is_one(status)) { - return (((a >> 22) & 0x1FF) =3D=3D 0x1FE) && (a & 0x003FFFFF); - } else { - return ((uint32_t)(a << 1) >=3D 0xFF800000); - } - } + return float32_is_any_nan(a_) && !float32_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -328,17 +319,21 @@ bool float32_is_quiet_nan(float32 a_, float_status *s= tatus) *-------------------------------------------------------------------------= ---*/ =20 bool float32_is_signaling_nan(float32 a_, float_status *status) +{ + return float32_is_any_nan(a_) && float32_nan_is_snan(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Determine if a float64 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float64_nan_is_snan(float64 a, float_status *status) { if (no_signaling_nans(status)) { - return 0; - } else { - uint32_t a =3D float32_val(a_); - if (snan_bit_is_one(status)) { - return ((uint32_t)(a << 1) >=3D 0xFF800000); - } else { - return (((a >> 22) & 0x1FF) =3D=3D 0x1FE) && (a & 0x003FFFFF); - } + return false; } + bool frac_msb_is_one =3D (a >> 51) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -348,17 +343,7 @@ bool float32_is_signaling_nan(float32 a_, float_status= *status) =20 bool float64_is_quiet_nan(float64 a_, float_status *status) { - if (no_signaling_nans(status)) { - return float64_is_any_nan(a_); - } else { - uint64_t a =3D float64_val(a_); - if (snan_bit_is_one(status)) { - return (((a >> 51) & 0xFFF) =3D=3D 0xFFE) - && (a & 0x0007FFFFFFFFFFFFULL); - } else { - return ((a << 1) >=3D 0xFFF0000000000000ULL); - } - } + return float64_is_any_nan(a_) && !float64_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -368,17 +353,7 @@ bool float64_is_quiet_nan(float64 a_, float_status *st= atus) =20 bool float64_is_signaling_nan(float64 a_, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - uint64_t a =3D float64_val(a_); - if (snan_bit_is_one(status)) { - return ((a << 1) >=3D 0xFFF0000000000000ULL); - } else { - return (((a >> 51) & 0xFFF) =3D=3D 0xFFE) - && (a & UINT64_C(0x0007FFFFFFFFFFFF)); - } - } + return float64_is_any_nan(a_) && float64_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -444,6 +419,19 @@ floatx80 floatx80_silence_nan(floatx80 a, float_status= *status) return a; } =20 +/*------------------------------------------------------------------------= ---- +| Determine if a float128 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float128_nan_is_snan(float128 a, float_status *status) +{ + if (no_signaling_nans(status)) { + return false; + } + bool frac_msb_is_one =3D (a.high >> 47) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); +} + /*------------------------------------------------------------------------= ---- | Returns 1 if the quadruple-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. @@ -451,17 +439,7 @@ floatx80 floatx80_silence_nan(floatx80 a, float_status= *status) =20 bool float128_is_quiet_nan(float128 a, float_status *status) { - if (no_signaling_nans(status)) { - return float128_is_any_nan(a); - } else { - if (snan_bit_is_one(status)) { - return (((a.high >> 47) & 0xFFFF) =3D=3D 0xFFFE) - && (a.low || (a.high & 0x00007FFFFFFFFFFFULL)); - } else { - return ((a.high << 1) >=3D 0xFFFF000000000000ULL) - && (a.low || (a.high & 0x0000FFFFFFFFFFFFULL)); - } - } + return float128_is_any_nan(a) && !float128_nan_is_snan(a, status); } =20 /*------------------------------------------------------------------------= ---- @@ -471,15 +449,5 @@ bool float128_is_quiet_nan(float128 a, float_status *s= tatus) =20 bool float128_is_signaling_nan(float128 a, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - if (snan_bit_is_one(status)) { - return ((a.high << 1) >=3D 0xFFFF000000000000ULL) - && (a.low || (a.high & 0x0000FFFFFFFFFFFFULL)); - } else { - return (((a.high >> 47) & 0xFFFF) =3D=3D 0xFFFE) - && (a.low || (a.high & UINT64_C(0x00007FFFFFFFFFFF))); - } - } + return float128_is_any_nan(a) && float128_nan_is_snan(a, status); } --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; 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[123.243.199.74]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2ad74f5dd7asm86543625ad.28.2026.02.23.00.22.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Feb 2026 00:22:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1771834931; x=1772439731; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=WILaMGNYgo59ciXOv8fCSdPpQjQ/av9tdzjHB1/JF6I=; b=lf384EcY1AT7BV1P5rip8nSAi4yqamo+4akZyRWPL+NzhefukGG3RAN0hsptElpVfN nqe562SY60rvHCuoBoq1VBNuH+YVExfcoC+svVw+m3sge5GTwyu0ZvgRlDGkjsxxN3gf JZhCour4EBezGj4SEDrx/p6vOrJ/XciPqsXfxbmDycKvILkKLK2yW5AISRMxLi+EDinb a7gU1ceJBqnN/ksNerux7b02R3pQ0dXD5uYU/UhrGvIgl7qioSwu/DHNPHk2Q4yABmbZ cA09ZBTWMBOow/AZBhNKwofWbvHC4PIyy7Kgc5PL6TP0j9IhX33X49T8zts+RpGs3H7c tsog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771834931; x=1772439731; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=WILaMGNYgo59ciXOv8fCSdPpQjQ/av9tdzjHB1/JF6I=; b=uwULEIEXX4QU9X+aBZAX9sq4Xr9YXXgQepEsVs15TOFvrVWMib8uB3DDG94YjbAgUU hX1vOABvxQUpTZKtVCuY6dkMZXCzbLNHldeB5YFySYBbQU4mQRurnKDnvkFw/L+eKHp5 02XclMCkKdsWsAMdhZOP+Qu9NNWV7DSm5MBk0VR2a3S+IfyvUIys9pKt0CsjKzURAYyg nTe4gtaLxr9S6tDUL4jAYj8gxOohlghD9Lq7GzmBXepAx3WoWHK/GPQz8QutTBGLhqtm kAVIBeSv+++cRU8K7iG75Zciv3jY/EE+x1a15zqp11Cwftp7wJjEmX20MkwvKaNzpl2S XhTQ== X-Gm-Message-State: AOJu0Yz9VxDdUztEy/5Rx6O1ckY1pCgZhnj7TgHuSLTyB5iRFCQ3pz0y +Ct3UQ5REUqBXVJ7sv0+OnqIEFc2xc6q+IOu9lnSUM7d7JKyF9TQR1P4Uf5WjR2HQtDKWODmNGp PvQ1vHONTyQ== X-Gm-Gg: ATEYQzxa1teJAm5F+UFknTXPszdajMbabEccJ6XwU/3Cz/y8/WlQJUUPdVWnfabkuCk yHFC0oi7nm1qJjVSUpNZE0TqbjdGQtJ9ttXA54eRzhnZyqqCHG4UQ8m4xrFQIRJ6fahA+g3k8NN c1UHzzcWwcMEiCu3xzEHoXAvuUK5ed0gfvpfdLXcDfV77mrqf3ghLD0otL4WqLqJcY7TV4B7OyK 7AAj9yldWzrn5WC84H/p5v6iI/FqJ3FSymAckVxicqY9zb2InZw23EpKH9D6BvC+IRNHE/ECscl bBuWmCu0KCAXs68422YJojaLiOjrzo5LUIOoyQNsKsPm05/erNqDQZLpih44X4NUqNyyf9/GL0/ iULAspmnBkAhGS7rca38mzOyitIbSm0pQXjzNsZ4bdPfAU+wUGq+BAZeXyat6afnkhXTFi3sISa abTITHk9nt+PHbxhcIY5Hj/DMyOA3x/XYokVxzGVPafPbVWMcWzK+bLLTlBmsQZ5QWHg== X-Received: by 2002:a17:903:13d0:b0:2aa:d5e8:f4dd with SMTP id d9443c01a7336-2ad74463ebamr79008715ad.15.1771834930930; Mon, 23 Feb 2026 00:22:10 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Cc: max.chou@sifive.com, chao.liu.zevorn@gmail.com Subject: [PATCH v5 2/9] fpu/softfloat: Refactor floatx80 format NaN classification to share code Date: Mon, 23 Feb 2026 19:21:47 +1100 Message-ID: <20260223082154.5623-3-richard.henderson@linaro.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260223082154.5623-1-richard.henderson@linaro.org> References: <20260223082154.5623-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::643; envelope-from=richard.henderson@linaro.org; helo=mail-pl1-x643.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1771834991764158501 Content-Type: text/plain; charset="utf-8" From: Max Chou The floatx80_is_[quiet|signaling]_nan functions contain duplicated logic that should be shared. This commit introduces floatx80_nan_is_snan helper function that determine if a NaN is signaling and change the return type of floatx80_is_[signaling|quiet]_nan to bool. Suggested-by: Richard Henderson Signed-off-by: Max Chou Reviewed-by: Richard Henderson Reviewed-by: Chao Liu Signed-off-by: Richard Henderson Message-ID: <20260204051756.667397-4-max.chou@sifive.com> --- include/fpu/softfloat.h | 4 +-- fpu/softfloat-specialize.c.inc | 53 ++++++++++++---------------------- 2 files changed, 21 insertions(+), 36 deletions(-) diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 66b0c47b5e..69b9041ef0 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -978,8 +978,8 @@ floatx80 floatx80_rem(floatx80, floatx80, float_status = *status); floatx80 floatx80_sqrt(floatx80, float_status *status); FloatRelation floatx80_compare(floatx80, floatx80, float_status *status); FloatRelation floatx80_compare_quiet(floatx80, floatx80, float_status *sta= tus); -int floatx80_is_quiet_nan(floatx80, float_status *status); -int floatx80_is_signaling_nan(floatx80, float_status *status); +bool floatx80_is_quiet_nan(floatx80, float_status *status); +bool floatx80_is_signaling_nan(floatx80, float_status *status); floatx80 floatx80_silence_nan(floatx80, float_status *status); floatx80 floatx80_scalbn(floatx80, int, float_status *status); =20 diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 7d2515c1fa..9ed968c79b 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -357,53 +357,38 @@ bool float64_is_signaling_nan(float64 a_, float_statu= s *status) } =20 /*------------------------------------------------------------------------= ---- -| Returns 1 if the extended double-precision floating-point value `a' is a -| quiet NaN; otherwise returns 0. This slightly differs from the same -| function for other types as floatx80 has an explicit bit. +| Determine if a floatx80 NaN is signaling NaN. +| The MSB of frac differs from the same function for other types as floatx= 80 +| has an explicit bit. *-------------------------------------------------------------------------= ---*/ =20 -int floatx80_is_quiet_nan(floatx80 a, float_status *status) +static bool floatx80_nan_is_snan(floatx80 a, float_status *status) { if (no_signaling_nans(status)) { - return floatx80_is_any_nan(a); - } else { - if (snan_bit_is_one(status)) { - uint64_t aLow; - - aLow =3D a.low & ~0x4000000000000000ULL; - return ((a.high & 0x7FFF) =3D=3D 0x7FFF) - && (aLow << 1) - && (a.low =3D=3D aLow); - } else { - return ((a.high & 0x7FFF) =3D=3D 0x7FFF) - && (UINT64_C(0x8000000000000000) <=3D ((uint64_t)(a.low <<= 1))); - } + return false; } + bool frac_msb_is_one =3D (a.low >> 62) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- | Returns 1 if the extended double-precision floating-point value `a' is a -| signaling NaN; otherwise returns 0. This slightly differs from the same -| function for other types as floatx80 has an explicit bit. +| quiet NaN; otherwise returns 0. *-------------------------------------------------------------------------= ---*/ =20 -int floatx80_is_signaling_nan(floatx80 a, float_status *status) +bool floatx80_is_quiet_nan(floatx80 a, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - if (snan_bit_is_one(status)) { - return ((a.high & 0x7FFF) =3D=3D 0x7FFF) - && ((a.low << 1) >=3D 0x8000000000000000ULL); - } else { - uint64_t aLow; + return floatx80_is_any_nan(a) && !floatx80_nan_is_snan(a, status); +} =20 - aLow =3D a.low & ~UINT64_C(0x4000000000000000); - return ((a.high & 0x7FFF) =3D=3D 0x7FFF) - && (uint64_t)(aLow << 1) - && (a.low =3D=3D aLow); - } - } +/*------------------------------------------------------------------------= ---- +| Returns 1 if the extended double-precision floating-point value `a' is a +| signaling NaN; otherwise returns 0. +*-------------------------------------------------------------------------= ---*/ + +bool floatx80_is_signaling_nan(floatx80 a, float_status *status) +{ + return floatx80_is_any_nan(a) && floatx80_nan_is_snan(a, status); } =20 /*------------------------------------------------------------------------= ---- --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1771834990; cv=none; d=zohomail.com; s=zohoarc; b=DYCMGJu89KfkPKrmGDkS3j7UH+7Yvd8n7snbaqTtsbz/fB9EfCuMaQfos4RqrNAq9PGcyR3YijfvW+Arb075lNkNz/O+RK62BNznL/IccBJmmHqKQyjQnW9Za8iuSXNqFJW2aS+eVJQOvKgPdeKN/doixKe2byXXD1RpFq5V1dE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1771834990; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=7P4L6KRGUfnJuZGklnenZefdnYuPN4EZ2NjRTD5rCHQ=; b=XyebBM6oquzouaPFLHBb9xyrHhWptomgqw/C2er+3arFBF4fQAoOeHMAYKsoADXPKn2DWfwbdvM55HYp3zrZwOKcH7aEp08qD0k54cSJ5vThUXFHXu62gWLBteWDcM6v5H+s/PP3HWkfAHevHt6d7Yr9qZ2QLRXNfrQjGRFAmjU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1771834990566621.7306199465919; Mon, 23 Feb 2026 00:23:10 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vuRCt-0001yk-JT; Mon, 23 Feb 2026 03:22:19 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vuRCs-0001yT-05 for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:18 -0500 Received: from mail-pg1-x52d.google.com ([2607:f8b0:4864:20::52d]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1vuRCq-0007tL-72 for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:17 -0500 Received: by mail-pg1-x52d.google.com with SMTP id 41be03b00d2f7-c61343f82d7so1362680a12.1 for ; Mon, 23 Feb 2026 00:22:15 -0800 (PST) Received: from stoup.. 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[123.243.199.74]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2ad74f5dd7asm86543625ad.28.2026.02.23.00.22.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Feb 2026 00:22:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1771834935; x=1772439735; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=7P4L6KRGUfnJuZGklnenZefdnYuPN4EZ2NjRTD5rCHQ=; b=uAlhqBwF2zjMjg3UGjo76YPmeLQMPz6jx48Z81mnh1vnNt/iAMDtAaJHER6X0TR8Sd CPYL6Q0/Kpv4uy3kcQw4l7i2rcT2Ayn+z9nP9CUlrBAxiUvfWJAX66ABRs/GJBiuuXGE gtnSxBgOaeNG3FxltT6/dxv05gaUUuMlxaQaYOShwx01O9VoN/4Rd0nclO7WXeINDGJH 5/qHIBi9ZVjfpsvaGxhWgmlklhlx5yfCJOI4NKLwkMUQhPXX5OnFQa7Wm3wvbqhyVz5u +uGUUSU251FPRzms12FF6NdoexUHX+jYixaRVtV1Nj0Zlt6Xt+SoMJ3wfbEB4AMZtPZY lYaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771834935; x=1772439735; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=7P4L6KRGUfnJuZGklnenZefdnYuPN4EZ2NjRTD5rCHQ=; b=a5TiMkBhUe5658bYfw+L71klPSqkp2XmbwMuAIB5QVd+0F/Xuk9f2XC2i7rDWSM6Fc 3LT38rfvnBtbNcrJ35/ATZbXlqQAsavcd91Tgn6Oa9l9HdmGzvUxwz2oa6Pp2wkM3QaD fmfGlg933s/i3mMufYfTeK1fO8uZTsfcAFYRmjj7XFdrUU0q6AovhTU6Xz6urveT2kE9 5/kcuOT1gufyTtoA3PH+xC8EeQNtCIBaFsjXDFtqQhzDFoHDtkb9Y1oTsZBvzaTc04dj yJ35R+vbtvUV0IEvPPtlDA12SbpTFWZhpbEzACwm4MTJPxWvLovpx1SR4NyIlPdhqOta Uj4g== X-Gm-Message-State: AOJu0YwTYFoYxPkUqHBzq9riLWzt5VMRYuts7wZLXRg3zrNEdNZzEoLT jtQsijSCbKWoXjY1kW8RFel8R1Kw9tVUe7V6EoNjXzGJ988K5tT0s+wDq+gMS+yQlf7kcijgFF0 xnKgvdqk= X-Gm-Gg: ATEYQzxSO8pTRpFCMiDdcReWTVDwZ5sDJD044jXkaSm9ras/NjW0HXX9hHWOiOi3xyL FRIIjp+cBpGnhYvBRDWiW7pRYJD2gtU9oEN4hnS7ZuWhFNvuHGubiMZ/eMHrclMO0elm+pTefxZ ShK8ofoEVHRNPH+T1ycXofubnRao+wBRwSozfnSMR62RRjrU9tmNtGKkXXGuKqj58Z/gw6E4vs3 R/Yimya/3nPm5ZQIAKlVdOakxDQ0kCh66Cw6Jz7mGGgxAbSibzb1I/cL6Ma680KgN1YceNI8pTG ZDNqmqzZyUOw/P8mHyy2RlTTlShKD18wBNZCGQ0nJbjHn5RgMq4gGBkJ+gPb4dRUYs6OZBzmV+G QaBFLB/XqOgB4LXIyzrbL0CinGSf3gUGmDb5XtKrMC87WZ6Rd9xnAKo65JwkrvC/l98cnnpkIQj PadGAA99FU57rgBr4km3Tr+6O7odZy/jrIH9VctXkOpKpSJEQXiMaZcFm7E5+T/rt4Xg== X-Received: by 2002:a17:902:cf10:b0:2ad:4029:9e01 with SMTP id d9443c01a7336-2ad74463f6fmr65391145ad.14.1771834934724; Mon, 23 Feb 2026 00:22:14 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Cc: max.chou@sifive.com, chao.liu.zevorn@gmail.com Subject: [PATCH v5 3/9] target/i386: Fix pseudo-NaN handling in FPATAN/FYL2XP1/FYL2X helpers Date: Mon, 23 Feb 2026 19:21:48 +1100 Message-ID: <20260223082154.5623-4-richard.henderson@linaro.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260223082154.5623-1-richard.henderson@linaro.org> References: <20260223082154.5623-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::52d; envelope-from=richard.henderson@linaro.org; helo=mail-pg1-x52d.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1771834992353154100 Content-Type: text/plain; charset="utf-8" From: Max Chou According to Intel's x87 FPU specification (Table 8-10, Vol. 1), arithmetic operations on operands in unsupported formats (including pseudo-NaNs) must return the QNaN floating-point indefinite value. The helper functions for FPATAN, FYL2XP1, and FYL2X incorrectly check for signaling NaN before checking for invalid encodings. This causes pseudo-NaNs to be treated as valid signaling NaNs and silenced, rather than being rejected as unsupported formats. Reorder the checks to test floatx80_invalid_encoding before floatx80_is_signaling_nan, matching the correct behavior already implemented in helper_fscale. Signed-off-by: Max Chou Reviewed-by: Richard Henderson Reviewed-by: Chao Liu Signed-off-by: Richard Henderson Message-ID: <20260204051756.667397-5-max.chou@sifive.com> --- target/i386/tcg/fpu_helper.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/target/i386/tcg/fpu_helper.c b/target/i386/tcg/fpu_helper.c index b3b23823fd..37c83ded38 100644 --- a/target/i386/tcg/fpu_helper.c +++ b/target/i386/tcg/fpu_helper.c @@ -1377,16 +1377,16 @@ void helper_fpatan(CPUX86State *env) int32_t arg1_exp =3D extractFloatx80Exp(ST1); bool arg1_sign =3D extractFloatx80Sign(ST1); =20 - if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + if (floatx80_invalid_encoding(ST0, &env->fp_status) || + floatx80_invalid_encoding(ST1, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST1 =3D floatx80_default_nan(&env->fp_status); + } else if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST0, &env->fp_status); } else if (floatx80_is_signaling_nan(ST1, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST1, &env->fp_status); - } else if (floatx80_invalid_encoding(ST0, &env->fp_status) || - floatx80_invalid_encoding(ST1, &env->fp_status)) { - float_raise(float_flag_invalid, &env->fp_status); - ST1 =3D floatx80_default_nan(&env->fp_status); } else if (floatx80_is_any_nan(ST0)) { ST1 =3D ST0; } else if (floatx80_is_any_nan(ST1)) { @@ -2061,16 +2061,16 @@ void helper_fyl2xp1(CPUX86State *env) int32_t arg1_exp =3D extractFloatx80Exp(ST1); bool arg1_sign =3D extractFloatx80Sign(ST1); =20 - if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + if (floatx80_invalid_encoding(ST0, &env->fp_status) || + floatx80_invalid_encoding(ST1, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST1 =3D floatx80_default_nan(&env->fp_status); + } else if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST0, &env->fp_status); } else if (floatx80_is_signaling_nan(ST1, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST1, &env->fp_status); - } else if (floatx80_invalid_encoding(ST0, &env->fp_status) || - floatx80_invalid_encoding(ST1, &env->fp_status)) { - float_raise(float_flag_invalid, &env->fp_status); - ST1 =3D floatx80_default_nan(&env->fp_status); } else if (floatx80_is_any_nan(ST0)) { ST1 =3D ST0; } else if (floatx80_is_any_nan(ST1)) { @@ -2159,16 +2159,16 @@ void helper_fyl2x(CPUX86State *env) int32_t arg1_exp =3D extractFloatx80Exp(ST1); bool arg1_sign =3D extractFloatx80Sign(ST1); =20 - if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { + if (floatx80_invalid_encoding(ST0, &env->fp_status) || + floatx80_invalid_encoding(ST1, &env->fp_status)) { + float_raise(float_flag_invalid, &env->fp_status); + ST1 =3D floatx80_default_nan(&env->fp_status); + } else if (floatx80_is_signaling_nan(ST0, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST0, &env->fp_status); } else if (floatx80_is_signaling_nan(ST1, &env->fp_status)) { float_raise(float_flag_invalid, &env->fp_status); ST1 =3D floatx80_silence_nan(ST1, &env->fp_status); - } else if (floatx80_invalid_encoding(ST0, &env->fp_status) || - floatx80_invalid_encoding(ST1, &env->fp_status)) { - float_raise(float_flag_invalid, &env->fp_status); - ST1 =3D floatx80_default_nan(&env->fp_status); } else if (floatx80_is_any_nan(ST0)) { ST1 =3D ST0; } else if (floatx80_is_any_nan(ST1)) { --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1771834970; cv=none; d=zohomail.com; s=zohoarc; b=k1TXUjwuK8oQsZpAKyopJgY8M401Sf0T5EJcyTQdHEu709I+aOivcAUx1M6619u+yGr8gAmyv3oTD00JzoAvWwwr27nziBjF7twXRkJHLwx6R4clVEkCKrXk29oNd5wquD7lDcGqQUQeiwTXPyNZJ2uvECmTvmeX+k87Qpd1JaU= ARC-Message-Signature: i=1; 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Reorganize canonicalize and uncanon_normal to use a switch statement, allowing more cases to be added trivially. Signed-off-by: Richard Henderson Reviewed-by: Chao Liu --- fpu/softfloat.c | 17 ++++++-- fpu/softfloat-parts.c.inc | 92 ++++++++++++++++++++++++--------------- 2 files changed, 69 insertions(+), 40 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 8740975348..8d8e576757 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -522,7 +522,16 @@ typedef struct { #define DECOMPOSED_BINARY_POINT 63 #define DECOMPOSED_IMPLICIT_BIT (1ull << DECOMPOSED_BINARY_POINT) =20 -/* Structure holding all of the relevant parameters for a format. +/* Format-specific handling of exp =3D=3D exp_max */ +typedef enum __attribute__((__packed__)) { + /* exp=3D=3Dmax, frac=3D=3D0 ? infinity : nan; this is ieee standard. = */ + float_expmax_ieee, + /* exp=3D=3Dmax is a normal number; no infinity or nan representation.= */ + float_expmax_normal, +} FloatFmtExpMaxKind; + +/* + * Structure holding all of the relevant parameters for a format. * exp_size: the size of the exponent field * exp_bias: the offset applied to the exponent field * exp_max: the maximum normalised exponent @@ -531,7 +540,7 @@ typedef struct { * The following are computed based the size of fraction * round_mask: bits below lsb which must be rounded * The following optional modifiers are available: - * arm_althp: handle ARM Alternative Half Precision + * exp_max_kind: affects how exp =3D=3D exp_max is interpreted * has_explicit_bit: has an explicit integer bit; this affects whether * the float_status floatx80_behaviour handling applies */ @@ -542,7 +551,7 @@ typedef struct { int exp_max; int frac_size; int frac_shift; - bool arm_althp; + FloatFmtExpMaxKind exp_max_kind; bool has_explicit_bit; uint64_t round_mask; } FloatFmt; @@ -566,7 +575,7 @@ static const FloatFmt float16_params =3D { =20 static const FloatFmt float16_params_ahp =3D { FLOAT_PARAMS(5, 10), - .arm_althp =3D true + .exp_max_kind =3D float_expmax_normal, }; =20 static const FloatFmt bfloat16_params =3D { diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 79b56014ab..455bbf281e 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -227,18 +227,30 @@ static void partsN(canonicalize)(FloatPartsN *p, floa= t_status *status, p->exp =3D fmt->frac_shift - fmt->exp_bias - shift + !has_pseudo_denormals; } - } else if (likely(p->exp < fmt->exp_max) || fmt->arm_althp) { - p->cls =3D float_class_normal; - p->exp -=3D fmt->exp_bias; - frac_shl(p, fmt->frac_shift); - p->frac_hi |=3D DECOMPOSED_IMPLICIT_BIT; - } else if (likely(frac_eqz(p))) { - p->cls =3D float_class_inf; - } else { - frac_shl(p, fmt->frac_shift); - p->cls =3D (parts_is_snan_frac(p->frac_hi, status) - ? float_class_snan : float_class_qnan); + return; } + if (unlikely(p->exp =3D=3D fmt->exp_max)) { + switch (fmt->exp_max_kind) { + case float_expmax_ieee: + if (likely(frac_eqz(p))) { + p->cls =3D float_class_inf; + } else { + frac_shl(p, fmt->frac_shift); + p->cls =3D (parts_is_snan_frac(p->frac_hi, status) + ? float_class_snan : float_class_qnan); + } + return; + case float_expmax_normal: + break; + default: + g_assert_not_reached(); + } + } + + p->cls =3D float_class_normal; + p->exp -=3D fmt->exp_bias; + frac_shl(p, fmt->frac_shift); + p->frac_hi |=3D DECOMPOSED_IMPLICIT_BIT; } =20 /* @@ -314,29 +326,37 @@ static void partsN(uncanon_normal)(FloatPartsN *p, fl= oat_status *s, p->frac_lo &=3D ~round_mask; } =20 - if (fmt->arm_althp) { - /* ARM Alt HP eschews Inf and NaN for a wider exponent. */ - if (unlikely(exp > exp_max)) { - /* Overflow. Return the maximum normal. */ - flags =3D float_flag_invalid; - exp =3D exp_max; - frac_allones(p); - p->frac_lo &=3D ~round_mask; - } - } else if (unlikely(exp >=3D exp_max)) { - flags |=3D float_flag_overflow; - if (s->rebias_overflow) { - exp -=3D fmt->exp_re_bias; - } else if (overflow_norm) { - flags |=3D float_flag_inexact; - exp =3D exp_max - 1; - frac_allones(p); - p->frac_lo &=3D ~round_mask; - } else { - flags |=3D float_flag_inexact; - p->cls =3D float_class_inf; - exp =3D exp_max; - frac_clear(p); + if (unlikely(exp >=3D exp_max)) { + switch (fmt->exp_max_kind) { + case float_expmax_ieee: + flags |=3D float_flag_overflow; + if (s->rebias_overflow) { + exp -=3D fmt->exp_re_bias; + } else if (overflow_norm) { + flags |=3D float_flag_inexact; + exp =3D exp_max - 1; + frac_allones(p); + p->frac_lo &=3D ~round_mask; + } else { + flags |=3D float_flag_inexact; + p->cls =3D float_class_inf; + exp =3D exp_max; + frac_clear(p); + } + break; + + case float_expmax_normal: + if (unlikely(exp > exp_max)) { + /* Overflow. Return the maximum normal. */ + flags =3D float_flag_invalid; + exp =3D exp_max; + frac_allones(p); + p->frac_lo &=3D ~round_mask; + } + break; + + default: + g_assert_not_reached(); } } frac_shr(p, frac_shift); @@ -434,13 +454,13 @@ static void partsN(uncanon)(FloatPartsN *p, float_sta= tus *s, frac_clear(p); return; case float_class_inf: - g_assert(!fmt->arm_althp); + assert(fmt->exp_max_kind =3D=3D float_expmax_ieee); p->exp =3D fmt->exp_max; frac_clear(p); return; case float_class_qnan: case float_class_snan: - g_assert(!fmt->arm_althp); + assert(fmt->exp_max_kind !=3D float_expmax_normal); p->exp =3D fmt->exp_max; frac_shr(p, fmt->frac_shift); return; --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1771835001; cv=none; d=zohomail.com; s=zohoarc; b=WIGer5diFTSbpKUb8AmJOCnM/j7tg+0eNq/xzXWszUsu6qwlUkaQFU5MgpvkR3wv08xj0oSJJ3e2hNjbHuH7rPdf9JvqLXE1mDgueoPV1KSmVjQPeW1q+BX7tP7zaaT15sEpm3sS42Ve2yQF82yXWex83rpUikL6eGmghAYDfbI= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1771835001; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=2SssxklF3WDtpYf8gJiGXdyp/wnJOPYk1NXsSx2j5Wc=; b=eD5oQtkqlQ3bPSSLGpF78Lb1rx8OEAhJYigSW8loe5MVEyJOttQ6IN372Ml2518LRxNbHKbglMr7Y8wzq51MSjqnOIS9buXnM3LOHJP9w1kXsE84uG5n+nsK+kihi9YEC6rP11Yt6toAXSE/yEkVmgZHOZHs2t0GMHSWeDDCV58= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1771835001728312.535530900523; Mon, 23 Feb 2026 00:23:21 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vuRD2-0002Bb-CA; Mon, 23 Feb 2026 03:22:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vuRCz-00025f-Ed for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:25 -0500 Received: from mail-pl1-x62e.google.com ([2607:f8b0:4864:20::62e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1vuRCx-000879-NG for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:25 -0500 Received: by mail-pl1-x62e.google.com with SMTP id d9443c01a7336-2a7a9b8ed69so35797585ad.2 for ; Mon, 23 Feb 2026 00:22:23 -0800 (PST) Received: from stoup.. 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Add a flag to control this effect. Signed-off-by: Max Chou [rth: Split out of a larger patch] Signed-off-by: Richard Henderson Reviewed-by: Chao Liu --- fpu/softfloat.c | 6 +++++- fpu/softfloat-parts.c.inc | 4 +++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 8d8e576757..9d06a1bb59 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -542,7 +542,9 @@ typedef enum __attribute__((__packed__)) { * The following optional modifiers are available: * exp_max_kind: affects how exp =3D=3D exp_max is interpreted * has_explicit_bit: has an explicit integer bit; this affects whether - * the float_status floatx80_behaviour handling applies + * the float_status floatx80_behaviour handling applies + * overflow_raises_invalid: for float_expmax_normal, raise invalid + * instead of overflow. */ typedef struct { int exp_size; @@ -553,6 +555,7 @@ typedef struct { int frac_shift; FloatFmtExpMaxKind exp_max_kind; bool has_explicit_bit; + bool overflow_raises_invalid; uint64_t round_mask; } FloatFmt; =20 @@ -576,6 +579,7 @@ static const FloatFmt float16_params =3D { static const FloatFmt float16_params_ahp =3D { FLOAT_PARAMS(5, 10), .exp_max_kind =3D float_expmax_normal, + .overflow_raises_invalid =3D true, }; =20 static const FloatFmt bfloat16_params =3D { diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 455bbf281e..4909ff7418 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -348,7 +348,9 @@ static void partsN(uncanon_normal)(FloatPartsN *p, floa= t_status *s, case float_expmax_normal: if (unlikely(exp > exp_max)) { /* Overflow. Return the maximum normal. */ - flags =3D float_flag_invalid; + flags =3D (fmt->overflow_raises_invalid + ? float_flag_invalid + : float_flag_overflow | float_flag_inexact); exp =3D exp_max; frac_allones(p); p->frac_lo &=3D ~round_mask; --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1771835006; cv=none; d=zohomail.com; s=zohoarc; b=TGcE4PNQYqmzodSGDLfiEtTcIR85KDqXrYcwbzy1wYC7oEYC3tlLtgtumaYSoPBUR5+NvBI485Mexvh677xZG/QiCf0mB2ETHnVzQM1jtch21Bgqk6Gu/Ty373xteThDtJMKb3FMv606p5HxSAHqw6RNMo9tTzkRCGkrQ6FuwV4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1771835006; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=7svS/Rh77Kfa8iIXf30fKW59Bgc3MJuDhuxENPk//BU=; b=kUNohh14fL4TvEso9ME6JhSLtVreWkU4Rzc51kBFRr/OvroLFi483nKbjd79+acyL3uUh+xkoTp8A1LqFL1V9ZvbJECvFFN1UBiMkTK7AnZMeeC63HWPafYQGTjz2RRZfyXXW5cuXBTHPaNrAKvj0Qo6CN526FGeiJS/ckysmyg= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1771835005993809.2556362847453; Mon, 23 Feb 2026 00:23:25 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vuRD5-0002He-EX; Mon, 23 Feb 2026 03:22:31 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vuRD3-0002Dk-0y for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:29 -0500 Received: from mail-pl1-x62c.google.com ([2607:f8b0:4864:20::62c]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1vuRD1-0008DD-1a for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:28 -0500 Received: by mail-pl1-x62c.google.com with SMTP id d9443c01a7336-2a91215c158so26961705ad.0 for ; Mon, 23 Feb 2026 00:22:26 -0800 (PST) Received: from stoup.. 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Add a parameter, currently always false. Signed-off-by: Max Chou [rth: Split out of a larger patch] Signed-off-by: Richard Henderson Reviewed-by: Chao Liu --- fpu/softfloat.c | 46 +++++++++++++++++++-------------------- fpu/softfloat-parts.c.inc | 15 ++++++++----- 2 files changed, 32 insertions(+), 29 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 9d06a1bb59..b3c4104854 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -771,20 +771,20 @@ static void parts128_canonicalize(FloatParts128 *p, f= loat_status *status, PARTS_GENERIC_64_128(canonicalize, A)(A, S, F) =20 static void parts64_uncanon_normal(FloatParts64 *p, float_status *status, - const FloatFmt *fmt); + const FloatFmt *fmt, bool saturate); static void parts128_uncanon_normal(FloatParts128 *p, float_status *status, - const FloatFmt *fmt); + const FloatFmt *fmt, bool saturate); =20 -#define parts_uncanon_normal(A, S, F) \ - PARTS_GENERIC_64_128(uncanon_normal, A)(A, S, F) +#define parts_uncanon_normal(A, S, F, X) \ + PARTS_GENERIC_64_128(uncanon_normal, A)(A, S, F, X) =20 static void parts64_uncanon(FloatParts64 *p, float_status *status, - const FloatFmt *fmt); + const FloatFmt *fmt, bool saturate); static void parts128_uncanon(FloatParts128 *p, float_status *status, - const FloatFmt *fmt); + const FloatFmt *fmt, bool saturate); =20 -#define parts_uncanon(A, S, F) \ - PARTS_GENERIC_64_128(uncanon, A)(A, S, F) +#define parts_uncanon(A, S, F, X) \ + PARTS_GENERIC_64_128(uncanon, A)(A, S, F, X) =20 static void parts64_add_normal(FloatParts64 *a, FloatParts64 *b); static void parts128_add_normal(FloatParts128 *a, FloatParts128 *b); @@ -1699,7 +1699,7 @@ static float16 float16a_round_pack_canonical(FloatPar= ts64 *p, float_status *s, const FloatFmt *params) { - parts_uncanon(p, s, params); + parts_uncanon(p, s, params, false); return float16_pack_raw(p); } =20 @@ -1712,7 +1712,7 @@ static float16 float16_round_pack_canonical(FloatPart= s64 *p, static bfloat16 bfloat16_round_pack_canonical(FloatParts64 *p, float_status *s) { - parts_uncanon(p, s, &bfloat16_params); + parts_uncanon(p, s, &bfloat16_params, false); return bfloat16_pack_raw(p); } =20 @@ -1726,7 +1726,7 @@ static void float32_unpack_canonical(FloatParts64 *p,= float32 f, static float32 float32_round_pack_canonical(FloatParts64 *p, float_status *s) { - parts_uncanon(p, s, &float32_params); + parts_uncanon(p, s, &float32_params, false); return float32_pack_raw(p); } =20 @@ -1740,7 +1740,7 @@ static void float64_unpack_canonical(FloatParts64 *p,= float64 f, static float64 float64_round_pack_canonical(FloatParts64 *p, float_status *s) { - parts_uncanon(p, s, &float64_params); + parts_uncanon(p, s, &float64_params, false); return float64_pack_raw(p); } =20 @@ -1789,7 +1789,7 @@ static float64 float64r32_pack_raw(FloatParts64 *p) static float64 float64r32_round_pack_canonical(FloatParts64 *p, float_status *s) { - parts_uncanon(p, s, &float32_params); + parts_uncanon(p, s, &float32_params, false); return float64r32_pack_raw(p); } =20 @@ -1803,7 +1803,7 @@ static void float128_unpack_canonical(FloatParts128 *= p, float128 f, static float128 float128_round_pack_canonical(FloatParts128 *p, float_status *s) { - parts_uncanon(p, s, &float128_params); + parts_uncanon(p, s, &float128_params, false); return float128_pack_raw(p); } =20 @@ -1851,7 +1851,7 @@ static floatx80 floatx80_round_pack_canonical(FloatPa= rts128 *p, case float_class_normal: case float_class_denormal: if (s->floatx80_rounding_precision =3D=3D floatx80_precision_x) { - parts_uncanon_normal(p, s, fmt); + parts_uncanon_normal(p, s, fmt, false); frac =3D p->frac_hi; exp =3D p->exp; } else { @@ -1860,7 +1860,7 @@ static floatx80 floatx80_round_pack_canonical(FloatPa= rts128 *p, p64.sign =3D p->sign; p64.exp =3D p->exp; frac_truncjam(&p64, p); - parts_uncanon_normal(&p64, s, fmt); + parts_uncanon_normal(&p64, s, fmt, false); frac =3D p64.frac; exp =3D p64.exp; } @@ -2258,7 +2258,7 @@ float16_muladd_scalbn(float16 a, float16 b, float16 c, pr =3D parts_muladd_scalbn(&pa, &pb, &pc, scale, flags, status); =20 /* Round before applying negate result. */ - parts_uncanon(pr, status, &float16_params); + parts_uncanon(pr, status, &float16_params, false); if ((flags & float_muladd_negate_result) && !is_nan(pr->cls)) { pr->sign ^=3D 1; } @@ -2283,7 +2283,7 @@ float32_muladd_scalbn(float32 a, float32 b, float32 c, pr =3D parts_muladd_scalbn(&pa, &pb, &pc, scale, flags, status); =20 /* Round before applying negate result. */ - parts_uncanon(pr, status, &float32_params); + parts_uncanon(pr, status, &float32_params, false); if ((flags & float_muladd_negate_result) && !is_nan(pr->cls)) { pr->sign ^=3D 1; } @@ -2302,7 +2302,7 @@ float64_muladd_scalbn(float64 a, float64 b, float64 c, pr =3D parts_muladd_scalbn(&pa, &pb, &pc, scale, flags, status); =20 /* Round before applying negate result. */ - parts_uncanon(pr, status, &float64_params); + parts_uncanon(pr, status, &float64_params, false); if ((flags & float_muladd_negate_result) && !is_nan(pr->cls)) { pr->sign ^=3D 1; } @@ -2461,7 +2461,7 @@ float64 float64r32_muladd(float64 a, float64 b, float= 64 c, pr =3D parts_muladd_scalbn(&pa, &pb, &pc, 0, flags, status); =20 /* Round before applying negate result. */ - parts_uncanon(pr, status, &float32_params); + parts_uncanon(pr, status, &float32_params, false); if ((flags & float_muladd_negate_result) && !is_nan(pr->cls)) { pr->sign ^=3D 1; } @@ -2479,7 +2479,7 @@ bfloat16 QEMU_FLATTEN bfloat16_muladd(bfloat16 a, bfl= oat16 b, bfloat16 c, pr =3D parts_muladd_scalbn(&pa, &pb, &pc, 0, flags, status); =20 /* Round before applying negate result. */ - parts_uncanon(pr, status, &bfloat16_params); + parts_uncanon(pr, status, &bfloat16_params, false); if ((flags & float_muladd_negate_result) && !is_nan(pr->cls)) { pr->sign ^=3D 1; } @@ -2497,7 +2497,7 @@ float128 QEMU_FLATTEN float128_muladd(float128 a, flo= at128 b, float128 c, pr =3D parts_muladd_scalbn(&pa, &pb, &pc, 0, flags, status); =20 /* Round before applying negate result. */ - parts_uncanon(pr, status, &float128_params); + parts_uncanon(pr, status, &float128_params, false); if ((flags & float_muladd_negate_result) && !is_nan(pr->cls)) { pr->sign ^=3D 1; } @@ -5435,7 +5435,7 @@ static void parts_s390_divide_to_integer(FloatParts64= *a, FloatParts64 *b, /* Round remainder to the target format */ *r =3D *r_precise; status->float_exception_flags =3D 0; - parts_uncanon(r, status, fmt); + parts_uncanon(r, status, fmt, false); r_flags =3D status->float_exception_flags; r->frac &=3D (1ULL << fmt->frac_size) - 1; parts_canonicalize(r, status, fmt); diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 4909ff7418..09be686645 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -258,9 +258,12 @@ static void partsN(canonicalize)(FloatPartsN *p, float= _status *status, * are FRAC_SHIFT bits that may require rounding at the bottom of the * fraction; these bits will be removed. The exponent will be biased * by EXP_BIAS and must be bounded by [EXP_MAX-1, 0]. + * + * The saturate parameter controls saturation behavior for formats that + * support it -- when true, overflow produces max normal instead of infini= ty. */ static void partsN(uncanon_normal)(FloatPartsN *p, float_status *s, - const FloatFmt *fmt) + const FloatFmt *fmt, bool saturate) { const int exp_max =3D fmt->exp_max; const int frac_shift =3D fmt->frac_shift; @@ -269,7 +272,7 @@ static void partsN(uncanon_normal)(FloatPartsN *p, floa= t_status *s, const uint64_t frac_lsbm1 =3D round_mask ^ (round_mask >> 1); const uint64_t roundeven_mask =3D round_mask | frac_lsb; uint64_t inc; - bool overflow_norm =3D false; + bool overflow_norm =3D saturate; int exp, flags =3D 0; =20 switch (s->float_rounding_mode) { @@ -294,11 +297,11 @@ static void partsN(uncanon_normal)(FloatPartsN *p, fl= oat_status *s, break; case float_round_up: inc =3D p->sign ? 0 : round_mask; - overflow_norm =3D p->sign; + overflow_norm |=3D p->sign; break; case float_round_down: inc =3D p->sign ? round_mask : 0; - overflow_norm =3D !p->sign; + overflow_norm |=3D !p->sign; break; case float_round_to_odd: overflow_norm =3D true; @@ -445,10 +448,10 @@ static void partsN(uncanon_normal)(FloatPartsN *p, fl= oat_status *s, } =20 static void partsN(uncanon)(FloatPartsN *p, float_status *s, - const FloatFmt *fmt) + const FloatFmt *fmt, bool saturate) { if (likely(is_anynorm(p->cls))) { - parts_uncanon_normal(p, s, fmt); + parts_uncanon_normal(p, s, fmt, saturate); } else { switch (p->cls) { case float_class_zero: --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1771834995; cv=none; d=zohomail.com; s=zohoarc; b=hhYObN0xPbtvIDVF30Is7lhKHChKevbTclyaDCRMZYDAa2SLiIM4WHV9kIEJIr/5zV7p6uJpC7zpBvEA59jIli1LaoV1YaOjhO87zdUjHNWrScYvyDpCFFzYCrTw9Gx7QKkDfe4kKz7QIkdtt/13EjJLFEOizh6AMr2yFDTV+hk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1771834995; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=qvXQWwSoWNG2h69uqztIMwRPFmzt/DYVgxqvm8Zixf0=; b=Bui7kOW5fyKfbGOXfH4nJnHDw7LtrxOURKTTULkeS0VyRmn507v3T5QzofdA9Kl09P1gJQQslg/0r69nyNxzylSn6wvelywh3RSzONu9sK36MojZyHmUYyd/AoStqDVKFkszNCzmA9GMNm14pxVMIwn6F9bxqwHGbtFUo0ake9E= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1771834995391602.862607865421; Mon, 23 Feb 2026 00:23:15 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vuRD8-0002Ka-Fa; Mon, 23 Feb 2026 03:22:34 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vuRD6-0002IW-BZ for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:32 -0500 Received: from mail-pl1-x62a.google.com ([2607:f8b0:4864:20::62a]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1vuRD4-0008KD-Ln for qemu-devel@nongnu.org; Mon, 23 Feb 2026 03:22:32 -0500 Received: by mail-pl1-x62a.google.com with SMTP id d9443c01a7336-2a7d98c1879so26021835ad.3 for ; Mon, 23 Feb 2026 00:22:30 -0800 (PST) Received: from stoup.. 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charset="utf-8" From: Max Chou Signed-off-by: Max Chou [rth: Split out of a larger patch] Signed-off-by: Richard Henderson Reviewed-by: Chao Liu --- include/fpu/softfloat-types.h | 5 +++ include/fpu/softfloat.h | 8 ++++ fpu/softfloat.c | 85 +++++++++++++++++++++++++++++++++++ 3 files changed, 98 insertions(+) diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index 8f82fdfc97..be7e2de6e3 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -119,6 +119,11 @@ typedef struct { */ typedef uint16_t bfloat16; =20 +/* + * Open Compute Project (OCP) Microscaling Formats + */ +typedef uint8_t float8_e5m2; + /* * Software IEC/IEEE floating-point underflow tininess-detection mode. */ diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 69b9041ef0..4385462992 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -189,6 +189,14 @@ float128 int128_to_float128(Int128, float_status *stat= us); float128 uint64_to_float128(uint64_t, float_status *status); float128 uint128_to_float128(Int128, float_status *status); =20 +/*------------------------------------------------------------------------= ---- +| OCP FP8 conversion routines. +*-------------------------------------------------------------------------= ---*/ + +bfloat16 float8_e5m2_to_bfloat16(float8_e5m2, float_status *status); +float8_e5m2 bfloat16_to_float8_e5m2(bfloat16, bool sat, float_status *stat= us); +float8_e5m2 float32_to_float8_e5m2(float32, bool sat, float_status *status= ); + /*------------------------------------------------------------------------= ---- | Software half-precision conversion routines. *-------------------------------------------------------------------------= ---*/ diff --git a/fpu/softfloat.c b/fpu/softfloat.c index b3c4104854..0dc769283d 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -572,6 +572,10 @@ typedef struct { .frac_shift =3D (-F - 1) & 63, \ .round_mask =3D (1ull << ((-F - 1) & 63)) - 1 =20 +static const FloatFmt float8_e5m2_params =3D { + FLOAT_PARAMS(5, 2) +}; + static const FloatFmt float16_params =3D { FLOAT_PARAMS(5, 10) }; @@ -627,6 +631,11 @@ static void unpack_raw64(FloatParts64 *r, const FloatF= mt *fmt, uint64_t raw) }; } =20 +static void QEMU_FLATTEN float8_e5m2_unpack_raw(FloatParts64 *p, float8_e5= m2 f) +{ + unpack_raw64(p, &float8_e5m2_params, f); +} + static void QEMU_FLATTEN float16_unpack_raw(FloatParts64 *p, float16 f) { unpack_raw64(p, &float16_params, f); @@ -684,6 +693,11 @@ static uint64_t pack_raw64(const FloatParts64 *p, cons= t FloatFmt *fmt) return ret; } =20 +static float8_e5m2 QEMU_FLATTEN float8_e5m2_pack_raw(const FloatParts64 *p) +{ + return pack_raw64(p, &float8_e5m2_params); +} + static float16 QEMU_FLATTEN float16_pack_raw(const FloatParts64 *p) { return make_float16(pack_raw64(p, &float16_params)); @@ -1675,6 +1689,13 @@ static const uint16_t rsqrt_tab[128] =3D { * Pack/unpack routines with a specific FloatFmt. */ =20 +static void float8_e5m2_unpack_canonical(FloatParts64 *p, float8_e5m2 f, + float_status *s) +{ + float8_e5m2_unpack_raw(p, f); + parts_canonicalize(p, s, &float8_e5m2_params); +} + static void float16a_unpack_canonical(FloatParts64 *p, float16 f, float_status *s, const FloatFmt *par= ams) { @@ -1695,6 +1716,14 @@ static void bfloat16_unpack_canonical(FloatParts64 *= p, bfloat16 f, parts_canonicalize(p, s, &bfloat16_params); } =20 +static float8_e5m2 float8_e5m2_round_pack_canonical(FloatParts64 *p, + float_status *s, + bool saturate) +{ + parts_uncanon(p, s, &float8_e5m2_params, saturate); + return float8_e5m2_pack_raw(p); +} + static float16 float16a_round_pack_canonical(FloatParts64 *p, float_status *s, const FloatFmt *params) @@ -2772,6 +2801,35 @@ static void parts_float_to_ahp(FloatParts64 *a, floa= t_status *s) } } =20 +static void parts_float_to_e5m2(FloatParts64 *a, float_status *s, bool sat= urate) +{ + switch (a->cls) { + case float_class_snan: + case float_class_qnan: + parts_return_nan(a, s); + break; + + case float_class_inf: + /* Per OCP, conversion in SATURATE mode bounds Inf to MAX. */ + if (saturate) { + a->cls =3D float_class_normal; + a->exp =3D float8_e5m2_params.exp_max - 1; + a->frac =3D MAKE_64BIT_MASK(float8_e5m2_params.frac_shift, + float8_e5m2_params.frac_size + 1); + } + break; + + case float_class_denormal: + float_raise(float_flag_input_denormal_used, s); + break; + case float_class_normal: + case float_class_zero: + break; + default: + g_assert_not_reached(); + } +} + static void parts64_float_to_float(FloatParts64 *a, float_status *s) { if (is_nan(a->cls)) { @@ -2836,6 +2894,15 @@ static void parts_float_to_float_widen(FloatParts128= *a, FloatParts64 *b, } } =20 +bfloat16 float8_e5m2_to_bfloat16(float8_e5m2 a, float_status *s) +{ + FloatParts64 p; + + float8_e5m2_unpack_canonical(&p, a, s); + parts_float_to_float(&p, s); + return bfloat16_round_pack_canonical(&p, s); +} + float32 float16_to_float32(float16 a, bool ieee, float_status *s) { const FloatFmt *fmt16 =3D ieee ? &float16_params : &float16_params_ahp; @@ -2856,6 +2923,15 @@ float64 float16_to_float64(float16 a, bool ieee, flo= at_status *s) return float64_round_pack_canonical(&p, s); } =20 +float8_e5m2 float32_to_float8_e5m2(float32 a, bool saturate, float_status = *s) +{ + FloatParts64 p; + + float32_unpack_canonical(&p, a, s); + parts_float_to_e5m2(&p, s, saturate); + return float8_e5m2_round_pack_canonical(&p, s, saturate); +} + float16 float32_to_float16(float32 a, bool ieee, float_status *s) { FloatParts64 p; @@ -2923,6 +2999,15 @@ float32 float64_to_float32(float64 a, float_status *= s) return float32_round_pack_canonical(&p, s); } =20 +float8_e5m2 bfloat16_to_float8_e5m2(bfloat16 a, bool saturate, float_statu= s *s) +{ + FloatParts64 p; + + bfloat16_unpack_canonical(&p, a, s); + parts_float_to_e5m2(&p, s, saturate); + return float8_e5m2_round_pack_canonical(&p, s, saturate); +} + float32 bfloat16_to_float32(bfloat16 a, float_status *s) { FloatParts64 p; --=20 2.43.0 From nobody Sun Apr 12 00:58:41 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; 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Mon, 23 Feb 2026 00:22:32 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Cc: max.chou@sifive.com, chao.liu.zevorn@gmail.com Subject: [PATCH v5 8/9] fpu: Add conversion routines for OCP FP8 E4M3 Date: Mon, 23 Feb 2026 19:21:53 +1100 Message-ID: <20260223082154.5623-9-richard.henderson@linaro.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260223082154.5623-1-richard.henderson@linaro.org> References: <20260223082154.5623-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::629; envelope-from=richard.henderson@linaro.org; helo=mail-pl1-x629.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1771835005884158500 Content-Type: text/plain; charset="utf-8" From: Max Chou Signed-off-by: Max Chou [rth: Split out of a larger patch; adjust overflow detection.] Signed-off-by: Richard Henderson Reviewed-by: Chao Liu --- include/fpu/softfloat-types.h | 1 + include/fpu/softfloat.h | 4 +++ fpu/softfloat.c | 62 +++++++++++++++++++++++++++++++++++ fpu/softfloat-parts.c.inc | 45 +++++++++++++++++++++++-- 4 files changed, 109 insertions(+), 3 deletions(-) diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index be7e2de6e3..9c84a101e5 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -122,6 +122,7 @@ typedef uint16_t bfloat16; /* * Open Compute Project (OCP) Microscaling Formats */ +typedef uint8_t float8_e4m3; typedef uint8_t float8_e5m2; =20 /* diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 4385462992..31d3f76d3f 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -193,6 +193,10 @@ float128 uint128_to_float128(Int128, float_status *sta= tus); | OCP FP8 conversion routines. *-------------------------------------------------------------------------= ---*/ =20 +bfloat16 float8_e4m3_to_bfloat16(float8_e4m3, float_status *status); +float8_e4m3 bfloat16_to_float8_e4m3(bfloat16, bool sat, float_status *stat= us); +float8_e4m3 float32_to_float8_e4m3(float32, bool sat, float_status *status= ); + bfloat16 float8_e5m2_to_bfloat16(float8_e5m2, float_status *status); float8_e5m2 bfloat16_to_float8_e5m2(bfloat16, bool sat, float_status *stat= us); float8_e5m2 float32_to_float8_e5m2(float32, bool sat, float_status *status= ); diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 0dc769283d..6e21882ab2 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -528,6 +528,8 @@ typedef enum __attribute__((__packed__)) { float_expmax_ieee, /* exp=3D=3Dmax is a normal number; no infinity or nan representation.= */ float_expmax_normal, + /* exp=3D=3Dmax, frac=3D=3Dmax ? nan : normal; no infinity representat= ion. */ + float_expmax_e4m3, } FloatFmtExpMaxKind; =20 /* @@ -572,6 +574,14 @@ typedef struct { .frac_shift =3D (-F - 1) & 63, \ .round_mask =3D (1ull << ((-F - 1) & 63)) - 1 =20 +static const FloatFmt float8_e4m3_params =3D { + FLOAT_PARAMS(4, 3), + .exp_max_kind =3D float_expmax_e4m3 +}; + +/* 110 << frac_shift, with the implicit bit set */ +#define E4M3_NORMAL_FRAC_MAX 0xe000000000000000ull + static const FloatFmt float8_e5m2_params =3D { FLOAT_PARAMS(5, 2) }; @@ -631,6 +641,11 @@ static void unpack_raw64(FloatParts64 *r, const FloatF= mt *fmt, uint64_t raw) }; } =20 +static void QEMU_FLATTEN float8_e4m3_unpack_raw(FloatParts64 *p, float8_e4= m3 f) +{ + unpack_raw64(p, &float8_e4m3_params, f); +} + static void QEMU_FLATTEN float8_e5m2_unpack_raw(FloatParts64 *p, float8_e5= m2 f) { unpack_raw64(p, &float8_e5m2_params, f); @@ -693,6 +708,11 @@ static uint64_t pack_raw64(const FloatParts64 *p, cons= t FloatFmt *fmt) return ret; } =20 +static float8_e4m3 QEMU_FLATTEN float8_e4m3_pack_raw(const FloatParts64 *p) +{ + return pack_raw64(p, &float8_e4m3_params); +} + static float8_e5m2 QEMU_FLATTEN float8_e5m2_pack_raw(const FloatParts64 *p) { return pack_raw64(p, &float8_e5m2_params); @@ -1689,6 +1709,13 @@ static const uint16_t rsqrt_tab[128] =3D { * Pack/unpack routines with a specific FloatFmt. */ =20 +static void float8_e4m3_unpack_canonical(FloatParts64 *p, float8_e4m3 f, + float_status *s) +{ + float8_e4m3_unpack_raw(p, f); + parts_canonicalize(p, s, &float8_e4m3_params); +} + static void float8_e5m2_unpack_canonical(FloatParts64 *p, float8_e5m2 f, float_status *s) { @@ -1716,6 +1743,14 @@ static void bfloat16_unpack_canonical(FloatParts64 *= p, bfloat16 f, parts_canonicalize(p, s, &bfloat16_params); } =20 +static float8_e4m3 float8_e4m3_round_pack_canonical(FloatParts64 *p, + float_status *s, + bool saturate) +{ + parts_uncanon(p, s, &float8_e4m3_params, saturate); + return float8_e4m3_pack_raw(p); +} + static float8_e5m2 float8_e5m2_round_pack_canonical(FloatParts64 *p, float_status *s, bool saturate) @@ -2894,6 +2929,15 @@ static void parts_float_to_float_widen(FloatParts128= *a, FloatParts64 *b, } } =20 +bfloat16 float8_e4m3_to_bfloat16(float8_e4m3 a, float_status *s) +{ + FloatParts64 p; + + float8_e4m3_unpack_canonical(&p, a, s); + parts_float_to_float(&p, s); + return bfloat16_round_pack_canonical(&p, s); +} + bfloat16 float8_e5m2_to_bfloat16(float8_e5m2 a, float_status *s) { FloatParts64 p; @@ -2923,6 +2967,15 @@ float64 float16_to_float64(float16 a, bool ieee, flo= at_status *s) return float64_round_pack_canonical(&p, s); } =20 +float8_e4m3 float32_to_float8_e4m3(float32 a, bool saturate, float_status = *s) +{ + FloatParts64 p; + + float32_unpack_canonical(&p, a, s); + parts_float_to_float(&p, s); + return float8_e4m3_round_pack_canonical(&p, s, saturate); +} + float8_e5m2 float32_to_float8_e5m2(float32 a, bool saturate, float_status = *s) { FloatParts64 p; @@ -2999,6 +3052,15 @@ float32 float64_to_float32(float64 a, float_status *= s) return float32_round_pack_canonical(&p, s); } =20 +float8_e4m3 bfloat16_to_float8_e4m3(bfloat16 a, bool saturate, float_statu= s *s) +{ + FloatParts64 p; + + bfloat16_unpack_canonical(&p, a, s); + parts_float_to_float(&p, s); + return float8_e4m3_round_pack_canonical(&p, s, saturate); +} + float8_e5m2 bfloat16_to_float8_e5m2(bfloat16 a, bool saturate, float_statu= s *s) { FloatParts64 p; diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 09be686645..61b07307bf 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -242,6 +242,15 @@ static void partsN(canonicalize)(FloatPartsN *p, float= _status *status, return; case float_expmax_normal: break; + case float_expmax_e4m3: + if (p->frac_hi =3D=3D 0b111) { + frac_shl(p, fmt->frac_shift); + p->cls =3D (parts_is_snan_frac(p->frac_hi, status) + ? float_class_snan : float_class_qnan); + return; + } + /* otherwise normal */ + break; default: g_assert_not_reached(); } @@ -262,6 +271,21 @@ static void partsN(canonicalize)(FloatPartsN *p, float= _status *status, * The saturate parameter controls saturation behavior for formats that * support it -- when true, overflow produces max normal instead of infini= ty. */ + +/* Helper for uncanon_normal and uncanon, for FP8 E4M3. */ +static void partsN(uncanon_e4m3_overflow)(FloatPartsN *p, float_status *s, + const FloatFmt *fmt, bool satura= te) +{ + assert(N =3D=3D 64); + float_raise(float_flag_overflow | float_flag_inexact, s); + if (saturate) { + p->exp =3D fmt->exp_max; + p->frac_hi =3D E4M3_NORMAL_FRAC_MAX; + } else { + parts_default_nan(p, s); + } +} + static void partsN(uncanon_normal)(FloatPartsN *p, float_status *s, const FloatFmt *fmt, bool saturate) { @@ -360,6 +384,12 @@ static void partsN(uncanon_normal)(FloatPartsN *p, flo= at_status *s, } break; =20 + case float_expmax_e4m3: + if (exp > exp_max || p->frac_hi > E4M3_NORMAL_FRAC_MAX) { + partsN(uncanon_e4m3_overflow)(p, s, fmt, overflow_norm= ); + } + break; + default: g_assert_not_reached(); } @@ -459,9 +489,18 @@ static void partsN(uncanon)(FloatPartsN *p, float_stat= us *s, frac_clear(p); return; case float_class_inf: - assert(fmt->exp_max_kind =3D=3D float_expmax_ieee); - p->exp =3D fmt->exp_max; - frac_clear(p); + switch (fmt->exp_max_kind) { + case float_expmax_ieee: + p->exp =3D fmt->exp_max; + frac_clear(p); + break; + case float_expmax_e4m3: + partsN(uncanon_e4m3_overflow)(p, s, fmt, saturate); 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charset="utf-8" From: Max Chou Signed-off-by: Max Chou [rth: Update for exp_max_kind] Signed-off-by: Richard Henderson Reviewed-by: Chao Liu --- include/fpu/softfloat-types.h | 1 + include/fpu/softfloat.h | 4 +++- fpu/softfloat.c | 26 ++++++++++++++++++++++++++ 3 files changed, 30 insertions(+), 1 deletion(-) diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index 9c84a101e5..ead146c22d 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -122,6 +122,7 @@ typedef uint16_t bfloat16; /* * Open Compute Project (OCP) Microscaling Formats */ +typedef uint8_t float4_e2m1; typedef uint8_t float8_e4m3; typedef uint8_t float8_e5m2; =20 diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 31d3f76d3f..8389a07b04 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -190,9 +190,11 @@ float128 uint64_to_float128(uint64_t, float_status *st= atus); float128 uint128_to_float128(Int128, float_status *status); =20 /*------------------------------------------------------------------------= ---- -| OCP FP8 conversion routines. +| OCP FP{4,8} conversion routines. *-------------------------------------------------------------------------= ---*/ =20 +float8_e4m3 float4_e2m1_to_float8_e4m3(float4_e2m1, float_status *status); + bfloat16 float8_e4m3_to_bfloat16(float8_e4m3, float_status *status); float8_e4m3 bfloat16_to_float8_e4m3(bfloat16, bool sat, float_status *stat= us); float8_e4m3 float32_to_float8_e4m3(float32, bool sat, float_status *status= ); diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 6e21882ab2..91c34307c8 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -574,6 +574,11 @@ typedef struct { .frac_shift =3D (-F - 1) & 63, \ .round_mask =3D (1ull << ((-F - 1) & 63)) - 1 =20 +static const FloatFmt float4_e2m1_params =3D { + FLOAT_PARAMS(2, 1), + .exp_max_kind =3D float_expmax_normal, +}; + static const FloatFmt float8_e4m3_params =3D { FLOAT_PARAMS(4, 3), .exp_max_kind =3D float_expmax_e4m3 @@ -641,6 +646,11 @@ static void unpack_raw64(FloatParts64 *r, const FloatF= mt *fmt, uint64_t raw) }; } =20 +static void QEMU_FLATTEN float4_e2m1_unpack_raw(FloatParts64 *p, float4_e2= m1 f) +{ + unpack_raw64(p, &float4_e2m1_params, f); +} + static void QEMU_FLATTEN float8_e4m3_unpack_raw(FloatParts64 *p, float8_e4= m3 f) { unpack_raw64(p, &float8_e4m3_params, f); @@ -1709,6 +1719,13 @@ static const uint16_t rsqrt_tab[128] =3D { * Pack/unpack routines with a specific FloatFmt. */ =20 +static void float4_e2m1_unpack_canonical(FloatParts64 *p, float4_e2m1 f, + float_status *s) +{ + float4_e2m1_unpack_raw(p, f); + parts_canonicalize(p, s, &float4_e2m1_params); +} + static void float8_e4m3_unpack_canonical(FloatParts64 *p, float8_e4m3 f, float_status *s) { @@ -2929,6 +2946,15 @@ static void parts_float_to_float_widen(FloatParts128= *a, FloatParts64 *b, } } =20 +float8_e4m3 float4_e2m1_to_float8_e4m3(float4_e2m1 a, float_status *s) +{ + FloatParts64 p; + + float4_e2m1_unpack_canonical(&p, a, s); + parts_float_to_float(&p, s); + return float8_e4m3_round_pack_canonical(&p, s, false); +} + bfloat16 float8_e4m3_to_bfloat16(float8_e4m3 a, float_status *s) { FloatParts64 p; --=20 2.43.0