From: "Lucas Mateus Castro (alqotel)" <lucas.araujo@eldorado.org.br>
Implement the following PowerISA v3.1 instructions:
xvf16ger2: VSX Vector 16-bit Floating-Point GER (rank-2 update)
xvf16ger2nn: VSX Vector 16-bit Floating-Point GER (rank-2 update) Negative
multiply, Negative accumulate
xvf16ger2np: VSX Vector 16-bit Floating-Point GER (rank-2 update) Negative
multiply, Positive accumulate
xvf16ger2pn: VSX Vector 16-bit Floating-Point GER (rank-2 update) Positive
multiply, Negative accumulate
xvf16ger2pp: VSX Vector 16-bit Floating-Point GER (rank-2 update) Positive
multiply, Positive accumulate
Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
---
include/fpu/softfloat.h | 9 ++++
target/ppc/cpu.h | 3 ++
target/ppc/fpu_helper.c | 65 +++++++++++++++++++++++++++++
target/ppc/helper.h | 1 +
target/ppc/insn32.decode | 6 +++
target/ppc/translate/vsx-impl.c.inc | 6 +++
6 files changed, 90 insertions(+)
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 3dcf20e3a2..63d7ff18f0 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -619,6 +619,15 @@ static inline float32 float32_chs(float32 a)
return make_float32(float32_val(a) ^ 0x80000000);
}
+static inline float32 float32_neg(float32 a)
+{
+ if (((a & 0x7f800000) == 0x7f800000) && (a & 0x007fffff)) {
+ return a;
+ } else {
+ return float32_chs(a);
+ }
+}
+
static inline bool float32_is_infinity(float32 a)
{
return (float32_val(a) & 0x7fffffff) == 0x7f800000;
diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index b5d7b35dda..91167f8cc0 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -225,6 +225,7 @@ typedef union _ppc_vsr_t {
int16_t s16[8];
int32_t s32[4];
int64_t s64[2];
+ float16 f16[8];
float32 f32[4];
float64 f64[2];
float128 f128;
@@ -2652,6 +2653,7 @@ static inline bool lsw_reg_in_range(int start, int nregs, int rx)
#define VsrSW(i) s32[i]
#define VsrD(i) u64[i]
#define VsrSD(i) s64[i]
+#define VsrHF(i) f16[i]
#define VsrSF(i) f32[i]
#define VsrDF(i) f64[i]
#else
@@ -2663,6 +2665,7 @@ static inline bool lsw_reg_in_range(int start, int nregs, int rx)
#define VsrSW(i) s32[3 - (i)]
#define VsrD(i) u64[1 - (i)]
#define VsrSD(i) s64[1 - (i)]
+#define VsrHF(i) f16[7 - (i)]
#define VsrSF(i) f32[3 - (i)]
#define VsrDF(i) f64[1 - (i)]
#endif
diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c
index 6b03666d09..c3aead642a 100644
--- a/target/ppc/fpu_helper.c
+++ b/target/ppc/fpu_helper.c
@@ -3478,6 +3478,67 @@ static inline bool ger_neg_acc_flag(uint32_t flag)
return flag & 0x4;
}
+#define float16_to_float32(A, PTR) float16_to_float32(A, true, PTR)
+
+#define GET_VSR(VSR, A, I, SRC_T, TARGET_T) \
+ SRC_T##_to_##TARGET_T(A->VSR(I), excp_ptr)
+
+#define VSXGER16(NAME, ORIG_T, OR_EL) \
+ void NAME(CPUPPCState *env, uint32_t a_r, uint32_t b_r, \
+ uint32_t at_r, uint32_t mask, uint32_t packed_flags) \
+ { \
+ ppc_vsr_t *at; \
+ float32 psum, aux_acc, va, vb, vc, vd; \
+ int i, j, xmsk_bit, ymsk_bit; \
+ uint8_t xmsk = mask & 0x0F; \
+ uint8_t ymsk = (mask >> 4) & 0x0F; \
+ uint8_t pmsk = (mask >> 8) & 0x3; \
+ ppc_vsr_t *b = cpu_vsr_ptr(env, b_r); \
+ ppc_vsr_t *a = cpu_vsr_ptr(env, a_r); \
+ float_status *excp_ptr = &env->fp_status; \
+ bool acc = ger_acc_flag(packed_flags); \
+ bool neg_acc = ger_neg_acc_flag(packed_flags); \
+ bool neg_mul = ger_neg_mul_flag(packed_flags); \
+ for (i = 0, xmsk_bit = 1 << 3; i < 4; i++, xmsk_bit >>= 1) { \
+ at = cpu_vsr_ptr(env, at_r + i); \
+ for (j = 0, ymsk_bit = 1 << 3; j < 4; j++, ymsk_bit >>= 1) {\
+ if ((xmsk_bit & xmsk) && (ymsk_bit & ymsk)) { \
+ va = !(pmsk & 2) ? float32_zero : \
+ GET_VSR(Vsr##OR_EL, a, \
+ 2 * i, ORIG_T, float32); \
+ vb = !(pmsk & 2) ? float32_zero : \
+ GET_VSR(Vsr##OR_EL, b, \
+ 2 * j, ORIG_T, float32); \
+ vc = !(pmsk & 1) ? float32_zero : \
+ GET_VSR(Vsr##OR_EL, a, \
+ 2 * i + 1, ORIG_T, float32);\
+ vd = !(pmsk & 1) ? float32_zero : \
+ GET_VSR(Vsr##OR_EL, b, \
+ 2 * j + 1, ORIG_T, float32);\
+ psum = float32_mul(va, vb, excp_ptr); \
+ psum = float32_muladd(vc, vd, psum, 0, excp_ptr); \
+ if (acc) { \
+ if (neg_mul) { \
+ psum = float32_neg(psum); \
+ } \
+ if (neg_acc) { \
+ aux_acc = float32_neg(at->VsrSF(j)); \
+ } else { \
+ aux_acc = at->VsrSF(j); \
+ } \
+ at->VsrSF(j) = float32_add(psum, aux_acc, \
+ excp_ptr); \
+ } else { \
+ at->VsrSF(j) = psum; \
+ } \
+ } else { \
+ at->VsrSF(j) = 0; \
+ } \
+ } \
+ } \
+ do_float_check_status(env, GETPC()); \
+ }
+
#define VSXGER(NAME, TYPE, EL) \
void NAME(CPUPPCState *env, uint32_t a_r, uint32_t b_r, \
uint32_t at_r, uint32_t mask, uint32_t packed_flags) \
@@ -3522,7 +3583,11 @@ static inline bool ger_neg_acc_flag(uint32_t flag)
do_float_check_status(env, GETPC()); \
}
+VSXGER16(helper_XVF16GER2, float16, HF)
VSXGER(helper_XVF32GER, float32, SF)
VSXGER(helper_XVF64GER, float64, DF)
+#undef VSXGER16
#undef VSXGER
+#undef GET_VSR
+#undef float16_to_float32
diff --git a/target/ppc/helper.h b/target/ppc/helper.h
index 7d725292b1..cc59a3b71d 100644
--- a/target/ppc/helper.h
+++ b/target/ppc/helper.h
@@ -540,6 +540,7 @@ DEF_HELPER_5(XXBLENDVD, void, vsr, vsr, vsr, vsr, i32)
DEF_HELPER_6(XVI4GER8, void, env, i32, i32, i32, i32, i32)
DEF_HELPER_6(XVI8GER4, void, env, i32, i32, i32, i32, i32)
DEF_HELPER_6(XVI16GER2, void, env, i32, i32, i32, i32, i32)
+DEF_HELPER_6(XVF16GER2, void, env, i32, i32, i32, i32, i32)
DEF_HELPER_6(XVF32GER, void, env, i32, i32, i32, i32, i32)
DEF_HELPER_6(XVF64GER, void, env, i32, i32, i32, i32, i32)
diff --git a/target/ppc/insn32.decode b/target/ppc/insn32.decode
index 9652ca286c..a204730d1d 100644
--- a/target/ppc/insn32.decode
+++ b/target/ppc/insn32.decode
@@ -736,6 +736,12 @@ XVI8GER4SPP 111011 ... -- ..... ..... 01100011 ..- @XX3_at xa=%xx_xa
XVI16GER2S 111011 ... -- ..... ..... 00101011 ..- @XX3_at xa=%xx_xa
XVI16GER2SPP 111011 ... -- ..... ..... 00101010 ..- @XX3_at xa=%xx_xa
+XVF16GER2 111011 ... -- ..... ..... 00010011 ..- @XX3_at xa=%xx_xa
+XVF16GER2PP 111011 ... -- ..... ..... 00010010 ..- @XX3_at xa=%xx_xa
+XVF16GER2PN 111011 ... -- ..... ..... 10010010 ..- @XX3_at xa=%xx_xa
+XVF16GER2NP 111011 ... -- ..... ..... 01010010 ..- @XX3_at xa=%xx_xa
+XVF16GER2NN 111011 ... -- ..... ..... 11010010 ..- @XX3_at xa=%xx_xa
+
XVF32GER 111011 ... -- ..... ..... 00011011 ..- @XX3_at xa=%xx_xa
XVF32GERPP 111011 ... -- ..... ..... 00011010 ..- @XX3_at xa=%xx_xa
XVF32GERPN 111011 ... -- ..... ..... 10011010 ..- @XX3_at xa=%xx_xa
diff --git a/target/ppc/translate/vsx-impl.c.inc b/target/ppc/translate/vsx-impl.c.inc
index b1fb0f31f3..9285e27159 100644
--- a/target/ppc/translate/vsx-impl.c.inc
+++ b/target/ppc/translate/vsx-impl.c.inc
@@ -2917,6 +2917,12 @@ TRANS64(PMXVI16GER2SPP, do_ger_MMIRR_XX3, GER_SPP, gen_helper_XVI16GER2)
#define GER_PN ger_pack_flags_xvf(true, false, true)
#define GER_NN ger_pack_flags_xvf(true, true, true)
+TRANS(XVF16GER2, do_ger_XX3, GER_NOP, gen_helper_XVF16GER2)
+TRANS(XVF16GER2PP, do_ger_XX3, GER_PP, gen_helper_XVF16GER2)
+TRANS(XVF16GER2PN, do_ger_XX3, GER_PN, gen_helper_XVF16GER2)
+TRANS(XVF16GER2NP, do_ger_XX3, GER_NP, gen_helper_XVF16GER2)
+TRANS(XVF16GER2NN, do_ger_XX3, GER_NN, gen_helper_XVF16GER2)
+
TRANS(XVF32GER, do_ger_XX3, GER_NOP, gen_helper_XVF32GER)
TRANS(XVF32GERPP, do_ger_XX3, GER_PP, gen_helper_XVF32GER)
TRANS(XVF32GERPN, do_ger_XX3, GER_PN, gen_helper_XVF32GER)
--
2.31.1On 4/26/22 05:50, Lucas Mateus Castro(alqotel) wrote:
> +#define VSXGER16(NAME, ORIG_T, OR_EL) \
> + void NAME(CPUPPCState *env, uint32_t a_r, uint32_t b_r, \
> + uint32_t at_r, uint32_t mask, uint32_t packed_flags) \
> + { \
> + ppc_vsr_t *at; \
> + float32 psum, aux_acc, va, vb, vc, vd; \
> + int i, j, xmsk_bit, ymsk_bit; \
> + uint8_t xmsk = mask & 0x0F; \
> + uint8_t ymsk = (mask >> 4) & 0x0F; \
> + uint8_t pmsk = (mask >> 8) & 0x3; \
> + ppc_vsr_t *b = cpu_vsr_ptr(env, b_r); \
> + ppc_vsr_t *a = cpu_vsr_ptr(env, a_r); \
> + float_status *excp_ptr = &env->fp_status; \
> + bool acc = ger_acc_flag(packed_flags); \
> + bool neg_acc = ger_neg_acc_flag(packed_flags); \
> + bool neg_mul = ger_neg_mul_flag(packed_flags); \
> + for (i = 0, xmsk_bit = 1 << 3; i < 4; i++, xmsk_bit >>= 1) { \
> + at = cpu_vsr_ptr(env, at_r + i); \
> + for (j = 0, ymsk_bit = 1 << 3; j < 4; j++, ymsk_bit >>= 1) {\
> + if ((xmsk_bit & xmsk) && (ymsk_bit & ymsk)) { \
> + va = !(pmsk & 2) ? float32_zero : \
> + GET_VSR(Vsr##OR_EL, a, \
> + 2 * i, ORIG_T, float32); \
> + vb = !(pmsk & 2) ? float32_zero : \
> + GET_VSR(Vsr##OR_EL, b, \
> + 2 * j, ORIG_T, float32); \
> + vc = !(pmsk & 1) ? float32_zero : \
> + GET_VSR(Vsr##OR_EL, a, \
> + 2 * i + 1, ORIG_T, float32);\
> + vd = !(pmsk & 1) ? float32_zero : \
> + GET_VSR(Vsr##OR_EL, b, \
> + 2 * j + 1, ORIG_T, float32);\
> + psum = float32_mul(va, vb, excp_ptr); \
> + psum = float32_muladd(vc, vd, psum, 0, excp_ptr); \
This isn't correct -- the intermediate 'prod' (the first multiply) is not rounded. I
think the correct way to implement this (barring new softfloat functions) is to compute
the intermediate product as float64 with float_round_to_odd, then float64r32_muladd into
the correct rounding mode to finish.
> + if (acc) { \
> + if (neg_mul) { \
> + psum = float32_neg(psum); \
> + } \
> + if (neg_acc) { \
> + aux_acc = float32_neg(at->VsrSF(j)); \
> + } else { \
> + aux_acc = at->VsrSF(j); \
> + } \
> + at->VsrSF(j) = float32_add(psum, aux_acc, \
> + excp_ptr); \
This one, thankfully, uses the rounded intermediate result 'msum', so is ok.
Please do convert this from a macro. Given that float16 and bfloat16 are addressed the
same, I think the only callback you need is the conversion from float16_to_float64. Drop
the bf16 accessor to ppc_vsr_t.
r~
On 26/04/2022 21:26, Richard Henderson wrote:
> On 4/26/22 05:50, Lucas Mateus Castro(alqotel) wrote:
>> +#define VSXGER16(NAME, ORIG_T,
>> OR_EL) \
>> + void NAME(CPUPPCState *env, uint32_t a_r, uint32_t
>> b_r, \
>> + uint32_t at_r, uint32_t mask, uint32_t
>> packed_flags) \
>> + { \
>> + ppc_vsr_t
>> *at; \
>> + float32 psum, aux_acc, va, vb, vc,
>> vd; \
>> + int i, j, xmsk_bit,
>> ymsk_bit; \
>> + uint8_t xmsk = mask &
>> 0x0F; \
>> + uint8_t ymsk = (mask >> 4) &
>> 0x0F; \
>> + uint8_t pmsk = (mask >> 8) &
>> 0x3; \
>> + ppc_vsr_t *b = cpu_vsr_ptr(env,
>> b_r); \
>> + ppc_vsr_t *a = cpu_vsr_ptr(env,
>> a_r); \
>> + float_status *excp_ptr =
>> &env->fp_status; \
>> + bool acc =
>> ger_acc_flag(packed_flags); \
>> + bool neg_acc =
>> ger_neg_acc_flag(packed_flags); \
>> + bool neg_mul =
>> ger_neg_mul_flag(packed_flags); \
>> + for (i = 0, xmsk_bit = 1 << 3; i < 4; i++, xmsk_bit >>= 1)
>> { \
>> + at = cpu_vsr_ptr(env, at_r +
>> i); \
>> + for (j = 0, ymsk_bit = 1 << 3; j < 4; j++, ymsk_bit >>=
>> 1) {\
>> + if ((xmsk_bit & xmsk) && (ymsk_bit & ymsk))
>> { \
>> + va = !(pmsk & 2) ? float32_zero
>> : \
>> + GET_VSR(Vsr##OR_EL,
>> a, \
>> + 2 * i, ORIG_T,
>> float32); \
>> + vb = !(pmsk & 2) ? float32_zero
>> : \
>> + GET_VSR(Vsr##OR_EL,
>> b, \
>> + 2 * j, ORIG_T,
>> float32); \
>> + vc = !(pmsk & 1) ? float32_zero
>> : \
>> + GET_VSR(Vsr##OR_EL,
>> a, \
>> + 2 * i + 1, ORIG_T,
>> float32);\
>> + vd = !(pmsk & 1) ? float32_zero
>> : \
>> + GET_VSR(Vsr##OR_EL,
>> b, \
>> + 2 * j + 1, ORIG_T,
>> float32);\
>> + psum = float32_mul(va, vb,
>> excp_ptr); \
>> + psum = float32_muladd(vc, vd, psum, 0,
>> excp_ptr); \
>
> This isn't correct -- the intermediate 'prod' (the first multiply) is
> not rounded. I
> think the correct way to implement this (barring new softfloat
> functions) is to compute
> the intermediate product as float64 with float_round_to_odd, then
> float64r32_muladd into
> the correct rounding mode to finish.
While not mentioned in the pseudocode the instruction description says:
- Let prod be the single-precision product of src10 and src20
Which I understand as the result of the first multiplication being
stored in a float32
But in xvbf16ger2* it's different (and I think this is the reason the
last patch is resulting in the wrong signal in some 0 and inf results),
the description says:
- Let prod be the product of src10 and src20, having infinite precision
and unbounded exponent range. - Let psum be the sum of the product,
src11 multiplied by src21, and prod, having infinite precision and
unbounded exponent range.
- Let r1 be the value psum with its significand rounded to 24-bit
precision using the rounding mode specified by RN, but retaining
unbounded exponent range (i.e., cannot overflow or underflow).
>
>> + if (acc)
>> { \
>> + if (neg_mul)
>> { \
>> + psum =
>> float32_neg(psum); \
>> + } \
>> + if (neg_acc)
>> { \
>> + aux_acc =
>> float32_neg(at->VsrSF(j)); \
>> + } else
>> { \
>> + aux_acc =
>> at->VsrSF(j); \
>> + } \
>> + at->VsrSF(j) = float32_add(psum,
>> aux_acc, \
>> + excp_ptr); \
>
> This one, thankfully, uses the rounded intermediate result 'msum', so
> is ok.
Yes this one is the easier one to deal with, in the description for the
xvf16ger2* it specifies that msum and the result is rounded to
single-precision and in the description for the xvbf16ger2 it specifies
that r1 is 'rounded to a 24-bit significand precision and 8-bit exponent
range (i.e., single-precision)'
>
> Please do convert this from a macro. Given that float16 and bfloat16
> are addressed the
> same, I think the only callback you need is the conversion from
> float16_to_float64. Drop
> the bf16 accessor to ppc_vsr_t.
>
Will do, although I'm considering instead of the callback being the
conversion, maybe have it be a 4 float multiplication
typedef float32 mul_4float(float16, float16, float16, float16);
Since float16 and bfloat16 are addressed the same, any thoughts?
>
> r~
--
Lucas Mateus M. Araujo e Castro
Instituto de Pesquisas ELDORADO
<https://www.eldorado.org.br/?utm_campaign=assinatura_de_e-mail&utm_medium=email&utm_source=RD+Station>
Departamento Computação Embarcada
Analista de Software Trainee
Aviso Legal - Disclaimer <https://www.eldorado.org.br/disclaimer.html>
On 4/27/22 14:11, Lucas Mateus Martins Araujo e Castro wrote: >> Please do convert this from a macro. Given that float16 and bfloat16 are addressed the >> same, I think the only callback you need is the conversion from float16_to_float64. Drop >> the bf16 accessor to ppc_vsr_t. >> > Will do, although I'm considering instead of the callback being the conversion, maybe have > it be a 4 float multiplication > typedef float32 mul_4float(float16, float16, float16, float16); > Since float16 and bfloat16 are addressed the same, any thoughts? The multiplication would be identical for the two types -- only the conversion is different. r~
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