target/arm: Convert PMUL.8 to gvec

The gvec form will be needed for implementing SVE2.

Extend the implementation to operate on uint64_t instead of uint32_t.
Use a counted inner loop instead of terminating when op1 goes to zero,
looking toward the required implementation for ARMv8.4-DIT.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200216214232.4230-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Richard Henderson 2020-02-16 13:42:30 -08:00 committed by Peter Maydell
parent 87b74e8b6e
commit a21bb78e58
5 changed files with 39 additions and 37 deletions

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@ -342,7 +342,6 @@ DEF_HELPER_2(neon_sub_u8, i32, i32, i32)
DEF_HELPER_2(neon_sub_u16, i32, i32, i32)
DEF_HELPER_2(neon_mul_u8, i32, i32, i32)
DEF_HELPER_2(neon_mul_u16, i32, i32, i32)
DEF_HELPER_2(neon_mul_p8, i32, i32, i32)
DEF_HELPER_2(neon_mull_p8, i64, i32, i32)
DEF_HELPER_2(neon_tst_u8, i32, i32, i32)
@ -696,6 +695,8 @@ DEF_HELPER_FLAGS_4(gvec_sshl_h, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_4(gvec_ushl_b, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_4(gvec_ushl_h, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, i32)
DEF_HELPER_FLAGS_4(gvec_pmul_b, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, i32)
#ifdef TARGET_AARCH64
#include "helper-a64.h"
#include "helper-sve.h"

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@ -1131,28 +1131,6 @@ NEON_VOP(mul_u16, neon_u16, 2)
/* Polynomial multiplication is like integer multiplication except the
partial products are XORed, not added. */
uint32_t HELPER(neon_mul_p8)(uint32_t op1, uint32_t op2)
{
uint32_t mask;
uint32_t result;
result = 0;
while (op1) {
mask = 0;
if (op1 & 1)
mask |= 0xff;
if (op1 & (1 << 8))
mask |= (0xff << 8);
if (op1 & (1 << 16))
mask |= (0xff << 16);
if (op1 & (1 << 24))
mask |= (0xff << 24);
result ^= op2 & mask;
op1 = (op1 >> 1) & 0x7f7f7f7f;
op2 = (op2 << 1) & 0xfefefefe;
}
return result;
}
uint64_t HELPER(neon_mull_p8)(uint32_t op1, uint32_t op2)
{
uint64_t result = 0;

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@ -11169,9 +11169,10 @@ static void disas_simd_3same_int(DisasContext *s, uint32_t insn)
case 0x13: /* MUL, PMUL */
if (!u) { /* MUL */
gen_gvec_fn3(s, is_q, rd, rn, rm, tcg_gen_gvec_mul, size);
return;
} else { /* PMUL */
gen_gvec_op3_ool(s, is_q, rd, rn, rm, 0, gen_helper_gvec_pmul_b);
}
break;
return;
case 0x12: /* MLA, MLS */
if (u) {
gen_gvec_op3(s, is_q, rd, rn, rm, &mls_op[size]);
@ -11301,11 +11302,6 @@ static void disas_simd_3same_int(DisasContext *s, uint32_t insn)
genfn = fns[size][u];
break;
}
case 0x13: /* MUL, PMUL */
assert(u); /* PMUL */
assert(size == 0);
genfn = gen_helper_neon_mul_p8;
break;
case 0x16: /* SQDMULH, SQRDMULH */
{
static NeonGenTwoOpEnvFn * const fns[2][2] = {

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@ -5007,16 +5007,17 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
case NEON_3R_VMUL: /* VMUL */
if (u) {
/* Polynomial case allows only P8 and is handled below. */
/* Polynomial case allows only P8. */
if (size != 0) {
return 1;
}
tcg_gen_gvec_3_ool(rd_ofs, rn_ofs, rm_ofs, vec_size, vec_size,
0, gen_helper_gvec_pmul_b);
} else {
tcg_gen_gvec_mul(size, rd_ofs, rn_ofs, rm_ofs,
vec_size, vec_size);
return 0;
}
break;
return 0;
case NEON_3R_VML: /* VMLA, VMLS */
tcg_gen_gvec_3(rd_ofs, rn_ofs, rm_ofs, vec_size, vec_size,
@ -5206,10 +5207,6 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
tmp2 = neon_load_reg(rd, pass);
gen_neon_add(size, tmp, tmp2);
break;
case NEON_3R_VMUL:
/* VMUL.P8; other cases already eliminated. */
gen_helper_neon_mul_p8(tmp, tmp, tmp2);
break;
case NEON_3R_VPMAX:
GEN_NEON_INTEGER_OP(pmax);
break;

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@ -1134,3 +1134,33 @@ void HELPER(gvec_ushl_h)(void *vd, void *vn, void *vm, uint32_t desc)
}
clear_tail(d, opr_sz, simd_maxsz(desc));
}
/*
* 8x8->8 polynomial multiply.
*
* Polynomial multiplication is like integer multiplication except the
* partial products are XORed, not added.
*
* TODO: expose this as a generic vector operation, as it is a common
* crypto building block.
*/
void HELPER(gvec_pmul_b)(void *vd, void *vn, void *vm, uint32_t desc)
{
intptr_t i, j, opr_sz = simd_oprsz(desc);
uint64_t *d = vd, *n = vn, *m = vm;
for (i = 0; i < opr_sz / 8; ++i) {
uint64_t nn = n[i];
uint64_t mm = m[i];
uint64_t rr = 0;
for (j = 0; j < 8; ++j) {
uint64_t mask = (nn & 0x0101010101010101ull) * 0xff;
rr ^= mm & mask;
mm = (mm << 1) & 0xfefefefefefefefeull;
nn >>= 1;
}
d[i] = rr;
}
clear_tail(d, opr_sz, simd_maxsz(desc));
}