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target/arm: Simplify SMMLA, SMMLAR, SMMLS, SMMLSR

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All of the inputs to these instructions are 32-bits.  Rather than
extend each input to 64-bits and then extract the high 32-bits of
the output, use tcg_gen_muls2_i32 and other 32-bit generator functions.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190808202616.13782-7-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Richard Henderson 2019-08-08 13:26:15 -07:00 committed by Peter Maydell
parent adefba76e8
commit 5f8cd06ebc
1 changed files with 26 additions and 46 deletions
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72
target/arm/translate.c
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@ -376,34 +376,6 @@ static void gen_revsh(TCGv_i32 var)
tcg_gen_ext16s_i32(var, var);
}
/* Return (b << 32) + a. Mark inputs as dead */
static TCGv_i64 gen_addq_msw(TCGv_i64 a, TCGv_i32 b)
{
TCGv_i64 tmp64 = tcg_temp_new_i64();
tcg_gen_extu_i32_i64(tmp64, b);
tcg_temp_free_i32(b);
tcg_gen_shli_i64(tmp64, tmp64, 32);
tcg_gen_add_i64(a, tmp64, a);
tcg_temp_free_i64(tmp64);
return a;
}
/* Return (b << 32) - a. Mark inputs as dead. */
static TCGv_i64 gen_subq_msw(TCGv_i64 a, TCGv_i32 b)
{
TCGv_i64 tmp64 = tcg_temp_new_i64();
tcg_gen_extu_i32_i64(tmp64, b);
tcg_temp_free_i32(b);
tcg_gen_shli_i64(tmp64, tmp64, 32);
tcg_gen_sub_i64(a, tmp64, a);
tcg_temp_free_i64(tmp64);
return a;
}
/* 32x32->64 multiply. Marks inputs as dead. */
static TCGv_i64 gen_mulu_i64_i32(TCGv_i32 a, TCGv_i32 b)
{
@ -8857,23 +8829,27 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
(SMMUL, SMMLA, SMMLS) */
tmp = load_reg(s, rm);
tmp2 = load_reg(s, rs);
tmp64 = gen_muls_i64_i32(tmp, tmp2);
tcg_gen_muls2_i32(tmp2, tmp, tmp, tmp2);
if (rd != 15) {
tmp = load_reg(s, rd);
tmp3 = load_reg(s, rd);
if (insn & (1 << 6)) {
tmp64 = gen_subq_msw(tmp64, tmp);
tcg_gen_sub_i32(tmp, tmp, tmp3);
} else {
tmp64 = gen_addq_msw(tmp64, tmp);
tcg_gen_add_i32(tmp, tmp, tmp3);
}
tcg_temp_free_i32(tmp3);
}
if (insn & (1 << 5)) {
tcg_gen_addi_i64(tmp64, tmp64, 0x80000000u);
/*
* Adding 0x80000000 to the 64-bit quantity
* means that we have carry in to the high
* word when the low word has the high bit set.
*/
tcg_gen_shri_i32(tmp2, tmp2, 31);
tcg_gen_add_i32(tmp, tmp, tmp2);
}
tcg_gen_shri_i64(tmp64, tmp64, 32);
tmp = tcg_temp_new_i32();
tcg_gen_extrl_i64_i32(tmp, tmp64);
tcg_temp_free_i64(tmp64);
tcg_temp_free_i32(tmp2);
store_reg(s, rn, tmp);
break;
case 0:
@ -10099,22 +10075,26 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn)
}
break;
case 5: case 6: /* 32 * 32 -> 32msb (SMMUL, SMMLA, SMMLS) */
tmp64 = gen_muls_i64_i32(tmp, tmp2);
tcg_gen_muls2_i32(tmp2, tmp, tmp, tmp2);
if (rs != 15) {
tmp = load_reg(s, rs);
tmp3 = load_reg(s, rs);
if (insn & (1 << 20)) {
tmp64 = gen_addq_msw(tmp64, tmp);
tcg_gen_add_i32(tmp, tmp, tmp3);
} else {
tmp64 = gen_subq_msw(tmp64, tmp);
tcg_gen_sub_i32(tmp, tmp, tmp3);
}
tcg_temp_free_i32(tmp3);
}
if (insn & (1 << 4)) {
tcg_gen_addi_i64(tmp64, tmp64, 0x80000000u);
/*
* Adding 0x80000000 to the 64-bit quantity
* means that we have carry in to the high
* word when the low word has the high bit set.
*/
tcg_gen_shri_i32(tmp2, tmp2, 31);
tcg_gen_add_i32(tmp, tmp, tmp2);
}
tcg_gen_shri_i64(tmp64, tmp64, 32);
tmp = tcg_temp_new_i32();
tcg_gen_extrl_i64_i32(tmp, tmp64);
tcg_temp_free_i64(tmp64);
tcg_temp_free_i32(tmp2);
break;
case 7: /* Unsigned sum of absolute differences. */
gen_helper_usad8(tmp, tmp, tmp2);