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[97.113.183.164]) by smtp.gmail.com with ESMTPSA id q15sm27246032pgt.12.2018.01.09.21.39.10 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 09 Jan 2018 21:39:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id; bh=XzqZqwsV4kKiwUA+mYrdiigFBy82UavXbafctX4idWs=; b=hK9IAy+CzjdAckKapFRXqGGTnyBZDc+lcvC/UAN9SHD/PXjs4uzvwL7zS51Ar+y2/h PRbT6hAgF6xobby4bl8vP+ZMBYnHYdmGpgZOuc6cuEWPJO2blhZ9J7hXyBWO1a7Sg+bS b1rxzSkMhMT/w//ELvcYWmXfsVQmfgC5NVvY7WQUrirb9THi1mYibO74Hgwr6DD/JNwF 1Ptw6EoIapYRxqk2j+rkFctYshOxP5+dojWWtZcs28aKDXMi5PryqHD7zU7QDwimT1Or dI/GaQ945yMclq3t80EaloD3SxH4e/ptWLGJ3tQHs3NEjEK/wUO84zomKC4UEGJkpJNQ tHzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id; bh=XzqZqwsV4kKiwUA+mYrdiigFBy82UavXbafctX4idWs=; b=ItnLtZanKJmBTqqGZ0rfpjSVkASBue92sceYJoAonYo2nFFsjM5S2xVmdaqAhHajPP QfdL8XwlPLBCwoMd/lea+PuRu2BVAutD1eiCKEWhDjh+tUIP+v5mtrJZf8s3l7UaEE6p DDvG2dsjFk184/1R0TaR3ku+69ob5mWaw+I4q+9Q0kUscm8Ekgv0eh82ZrSx0QrJJ/g+ uGRgViQCQsvlHUFTUpMhsS6wCKqlJlcYgcGw3jRKYKugvb8F+GECYs/amHprdcdxrPZR ovlUCmwQ+3AJsg+E7LkEf1n3Pt5bCc2ATVWlv1NpfE3eYHgp/9CS7D3V5B5vMoXCtVck jgsA== X-Gm-Message-State: AKGB3mJfRzTl+ViKaDb+OcrsTjxHRiccwfx8rmNMawkGgVc6X+DoJXWZ WWcGOwEUuEnoleg4Oia6aTfAOdvG X-Google-Smtp-Source: ACJfBotdWfpZV5qfOlqhFX01NsCBN1BwOtOi0AP6wW5RQ+smxLMT4UfHwhGB+N2G07MCkIFgn8yszg== X-Received: by 10.84.240.71 with SMTP id h7mr17803322plt.418.1515562751478; Tue, 09 Jan 2018 21:39:11 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Date: Tue, 9 Jan 2018 21:39:08 -0800 Message-Id: <1515562748-32287-1-git-send-email-rth@twiddle.net> X-Mailer: git-send-email 1.8.3.1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:400e:c01::243 Subject: [Qemu-devel] [PATCH] tcg/arm: Fix double-word comparisons X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, pbonzini@redhat.com, mdroth@linux.vnet.ibm.com, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZohoMail: RDKM_2 RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The code sequence we were generating was only good for unsigned comparisons. For signed comparisions, use the sequence from gcc. Fixes booting of ppc64 firmware, with a patch changing the code sequence for ppc comparisons. Signed-off-by: Richard Henderson Tested-by: Michael Roth --- tcg/arm/tcg-target.inc.c | 112 +++++++++++++++++++++++++++++++++----------= ---- 1 file changed, 80 insertions(+), 32 deletions(-) diff --git a/tcg/arm/tcg-target.inc.c b/tcg/arm/tcg-target.inc.c index 98a1253..b9890c8 100644 --- a/tcg/arm/tcg-target.inc.c +++ b/tcg/arm/tcg-target.inc.c @@ -239,10 +239,11 @@ static void patch_reloc(tcg_insn_unit *code_ptr, int = type, } } =20 -#define TCG_CT_CONST_ARM 0x100 -#define TCG_CT_CONST_INV 0x200 -#define TCG_CT_CONST_NEG 0x400 -#define TCG_CT_CONST_ZERO 0x800 +#define TCG_CT_CONST_ARM 0x0100 +#define TCG_CT_CONST_INV 0x0200 +#define TCG_CT_CONST_NEG 0x0400 +#define TCG_CT_CONST_INVNEG 0x0800 +#define TCG_CT_CONST_ZERO 0x1000 =20 /* parse target specific constraints */ static const char *target_parse_constraint(TCGArgConstraint *ct, @@ -258,6 +259,9 @@ static const char *target_parse_constraint(TCGArgConstr= aint *ct, case 'N': /* The gcc constraint letter is L, already used here. */ ct->ct |=3D TCG_CT_CONST_NEG; break; + case 'M': + ct->ct |=3D TCG_CT_CONST_INVNEG; + break; case 'Z': ct->ct |=3D TCG_CT_CONST_ZERO; break; @@ -351,8 +355,7 @@ static inline int check_fit_imm(uint32_t imm) static inline int tcg_target_const_match(tcg_target_long val, TCGType type, const TCGArgConstraint *arg_ct) { - int ct; - ct =3D arg_ct->ct; + int ct =3D arg_ct->ct; if (ct & TCG_CT_CONST) { return 1; } else if ((ct & TCG_CT_CONST_ARM) && check_fit_imm(val)) { @@ -361,6 +364,9 @@ static inline int tcg_target_const_match(tcg_target_lon= g val, TCGType type, return 1; } else if ((ct & TCG_CT_CONST_NEG) && check_fit_imm(-val)) { return 1; + } else if ((ct & TCG_CT_CONST_INVNEG) + && check_fit_imm(~val) && check_fit_imm(-val)) { + return 1; } else if ((ct & TCG_CT_CONST_ZERO) && val =3D=3D 0) { return 1; } else { @@ -1103,6 +1109,64 @@ static inline void tcg_out_mb(TCGContext *s, TCGArg = a0) } } =20 +static TCGCond tcg_out_cmp2(TCGContext *s, const TCGArg *args, + const int *const_args) +{ + TCGReg al =3D args[0]; + TCGReg ah =3D args[1]; + TCGArg bl =3D args[2]; + TCGArg bh =3D args[3]; + TCGCond cond =3D args[4]; + int const_bl =3D const_args[2]; + int const_bh =3D const_args[3]; + + switch (cond) { + case TCG_COND_EQ: + case TCG_COND_NE: + case TCG_COND_LTU: + case TCG_COND_LEU: + case TCG_COND_GTU: + case TCG_COND_GEU: + /* We perform a conditional comparision. If the high half is + equal, then overwrite the flags with the comparison of the + low half. The resulting flags cover the whole. */ + tcg_out_dat_rIN(s, COND_AL, ARITH_CMP, ARITH_CMN, 0, ah, bh, const= _bh); + tcg_out_dat_rIN(s, COND_EQ, ARITH_CMP, ARITH_CMN, 0, al, bl, const= _bl); + return cond; + + case TCG_COND_LT: + case TCG_COND_GE: + /* We perform a double-word subtraction and examine the result. + We do not actually need the result of the subtract, so the + low part "subtract" is a compare. For the high half we have + no choice but to compute into a temporary. */ + tcg_out_dat_rIN(s, COND_AL, ARITH_CMP, ARITH_CMN, 0, al, bl, const= _bl); + tcg_out_dat_rIK(s, COND_AL, ARITH_SBC | TO_CPSR, ARITH_ADC | TO_CP= SR, + TCG_REG_TMP, ah, bh, const_bh); + return cond; + + case TCG_COND_LE: + case TCG_COND_GT: + /* Similar, but with swapped arguments. And of course we must + force the immediates into a register. */ + if (const_bl) { + tcg_out_movi(s, TCG_TYPE_REG, TCG_REG_TMP, bl); + bl =3D TCG_REG_TMP; + } + tcg_out_dat_rIN(s, COND_AL, ARITH_CMP, ARITH_CMN, 0, bl, al, 0); + if (const_bh) { + tcg_out_movi(s, TCG_TYPE_REG, TCG_REG_TMP, bh); + bh =3D TCG_REG_TMP; + } + tcg_out_dat_rIK(s, COND_AL, ARITH_SBC | TO_CPSR, ARITH_ADC | TO_CP= SR, + TCG_REG_TMP, bh, ah, 0); + return tcg_swap_cond(cond); + + default: + g_assert_not_reached(); + } +} + #ifdef CONFIG_SOFTMMU #include "tcg-ldst.inc.c" =20 @@ -1964,22 +2028,6 @@ static inline void tcg_out_op(TCGContext *s, TCGOpco= de opc, tcg_out_goto_label(s, tcg_cond_to_arm_cond[args[2]], arg_label(args[3])); break; - case INDEX_op_brcond2_i32: - /* The resulting conditions are: - * TCG_COND_EQ --> a0 =3D=3D a2 && a1 =3D=3D a3, - * TCG_COND_NE --> (a0 !=3D a2 && a1 =3D=3D a3) || a1 !=3D a3, - * TCG_COND_LT(U) --> (a0 < a2 && a1 =3D=3D a3) || a1 < a3, - * TCG_COND_GE(U) --> (a0 >=3D a2 && a1 =3D=3D a3) || (a1 >=3D a3 = && a1 !=3D a3), - * TCG_COND_LE(U) --> (a0 <=3D a2 && a1 =3D=3D a3) || (a1 <=3D a3 = && a1 !=3D a3), - * TCG_COND_GT(U) --> (a0 > a2 && a1 =3D=3D a3) || a1 > a3, - */ - tcg_out_dat_rIN(s, COND_AL, ARITH_CMP, ARITH_CMN, 0, - args[1], args[3], const_args[3]); - tcg_out_dat_rIN(s, COND_EQ, ARITH_CMP, ARITH_CMN, 0, - args[0], args[2], const_args[2]); - tcg_out_goto_label(s, tcg_cond_to_arm_cond[args[4]], - arg_label(args[5])); - break; case INDEX_op_setcond_i32: tcg_out_dat_rIN(s, COND_AL, ARITH_CMP, ARITH_CMN, 0, args[1], args[2], const_args[2]); @@ -1988,15 +2036,15 @@ static inline void tcg_out_op(TCGContext *s, TCGOpc= ode opc, tcg_out_dat_imm(s, tcg_cond_to_arm_cond[tcg_invert_cond(args[3])], ARITH_MOV, args[0], 0, 0); break; + + case INDEX_op_brcond2_i32: + c =3D tcg_out_cmp2(s, args, const_args); + tcg_out_goto_label(s, tcg_cond_to_arm_cond[c], arg_label(args[5])); + break; case INDEX_op_setcond2_i32: - /* See brcond2_i32 comment */ - tcg_out_dat_rIN(s, COND_AL, ARITH_CMP, ARITH_CMN, 0, - args[2], args[4], const_args[4]); - tcg_out_dat_rIN(s, COND_EQ, ARITH_CMP, ARITH_CMN, 0, - args[1], args[3], const_args[3]); - tcg_out_dat_imm(s, tcg_cond_to_arm_cond[args[5]], - ARITH_MOV, args[0], 0, 1); - tcg_out_dat_imm(s, tcg_cond_to_arm_cond[tcg_invert_cond(args[5])], + c =3D tcg_out_cmp2(s, args + 1, const_args + 1); + tcg_out_dat_imm(s, tcg_cond_to_arm_cond[c], ARITH_MOV, args[0], 0,= 1); + tcg_out_dat_imm(s, tcg_cond_to_arm_cond[tcg_invert_cond(c)], ARITH_MOV, args[0], 0, 0); break; =20 @@ -2093,9 +2141,9 @@ static const TCGTargetOpDef *tcg_target_op_def(TCGOpc= ode op) static const TCGTargetOpDef sub2 =3D { .args_ct_str =3D { "r", "r", "rI", "rI", "rIN", "rIK" } }; static const TCGTargetOpDef br2 - =3D { .args_ct_str =3D { "r", "r", "rIN", "rIN" } }; + =3D { .args_ct_str =3D { "r", "r", "rIM", "rIM" } }; static const TCGTargetOpDef setc2 - =3D { .args_ct_str =3D { "r", "r", "r", "rIN", "rIN" } }; + =3D { .args_ct_str =3D { "r", "r", "r", "rIM", "rIM" } }; =20 switch (op) { case INDEX_op_goto_ptr: --=20 1.8.3.1