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author | Richard Henderson <richard.henderson@linaro.org> | 2022-09-07 09:25:06 +0200 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-10-18 13:58:05 +0200 |
commit | d4af67a27a817c2e96b7de176045fd95e2e9420b (patch) | |
tree | 307f7875885e577cc1bc7d7dda917f2f3788e533 | |
parent | 7906847768613ea6b6e737f3295c77cdb4ff67f4 (diff) | |
download | qemu-d4af67a27a817c2e96b7de176045fd95e2e9420b.zip qemu-d4af67a27a817c2e96b7de176045fd95e2e9420b.tar.gz qemu-d4af67a27a817c2e96b7de176045fd95e2e9420b.tar.bz2 |
target/i386: Use tcg gvec ops for pmovmskb
As pmovmskb is used by strlen et al, this is the third
highest overhead sse operation at %0.8.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
[Reorganize to generate code for any vector size. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r-- | target/i386/tcg/emit.c.inc | 88 |
1 files changed, 83 insertions, 5 deletions
diff --git a/target/i386/tcg/emit.c.inc b/target/i386/tcg/emit.c.inc index 062c92e..ad93094 100644 --- a/target/i386/tcg/emit.c.inc +++ b/target/i386/tcg/emit.c.inc @@ -1191,14 +1191,92 @@ static void gen_PINSR(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode) gen_pinsr(s, env, decode, decode->op[2].ot); } +static void gen_pmovmskb_i64(TCGv_i64 d, TCGv_i64 s) +{ + TCGv_i64 t = tcg_temp_new_i64(); + + tcg_gen_andi_i64(d, s, 0x8080808080808080ull); + + /* + * After each shift+or pair: + * 0: a.......b.......c.......d.......e.......f.......g.......h....... + * 7: ab......bc......cd......de......ef......fg......gh......h....... + * 14: abcd....bcde....cdef....defg....efgh....fgh.....gh......h....... + * 28: abcdefghbcdefgh.cdefgh..defgh...efgh....fgh.....gh......h....... + * The result is left in the high bits of the word. + */ + tcg_gen_shli_i64(t, d, 7); + tcg_gen_or_i64(d, d, t); + tcg_gen_shli_i64(t, d, 14); + tcg_gen_or_i64(d, d, t); + tcg_gen_shli_i64(t, d, 28); + tcg_gen_or_i64(d, d, t); +} + +static void gen_pmovmskb_vec(unsigned vece, TCGv_vec d, TCGv_vec s) +{ + TCGv_vec t = tcg_temp_new_vec_matching(d); + TCGv_vec m = tcg_constant_vec_matching(d, MO_8, 0x80); + + /* See above */ + tcg_gen_and_vec(vece, d, s, m); + tcg_gen_shli_vec(vece, t, d, 7); + tcg_gen_or_vec(vece, d, d, t); + tcg_gen_shli_vec(vece, t, d, 14); + tcg_gen_or_vec(vece, d, d, t); + tcg_gen_shli_vec(vece, t, d, 28); + tcg_gen_or_vec(vece, d, d, t); +} + +#ifdef TARGET_X86_64 +#define TCG_TARGET_HAS_extract2_tl TCG_TARGET_HAS_extract2_i64 +#else +#define TCG_TARGET_HAS_extract2_tl TCG_TARGET_HAS_extract2_i32 +#endif + static void gen_PMOVMSKB(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode) { - if (s->prefix & PREFIX_DATA) { - gen_helper_pmovmskb_xmm(s->tmp2_i32, cpu_env, OP_PTR2); - } else { - gen_helper_pmovmskb_mmx(s->tmp2_i32, cpu_env, OP_PTR2); + static const TCGOpcode vecop_list[] = { INDEX_op_shli_vec, 0 }; + static const GVecGen2 g = { + .fni8 = gen_pmovmskb_i64, + .fniv = gen_pmovmskb_vec, + .opt_opc = vecop_list, + .vece = MO_64, + .prefer_i64 = TCG_TARGET_REG_BITS == 64 + }; + MemOp ot = decode->op[2].ot; + int vec_len = vector_len(s, decode); + TCGv t = tcg_temp_new(); + + tcg_gen_gvec_2(offsetof(CPUX86State, xmm_t0) + xmm_offset(ot), decode->op[2].offset, + vec_len, vec_len, &g); + tcg_gen_ld8u_tl(s->T0, cpu_env, offsetof(CPUX86State, xmm_t0.ZMM_B(vec_len - 1))); + while (vec_len > 8) { + vec_len -= 8; + if (TCG_TARGET_HAS_extract2_tl) { + /* + * Load the next byte of the result into the high byte of T. + * TCG does a similar expansion of deposit to shl+extract2; by + * loading the whole word, the shift left is avoided. + */ +#ifdef TARGET_X86_64 + tcg_gen_ld_tl(t, cpu_env, offsetof(CPUX86State, xmm_t0.ZMM_Q((vec_len - 1) / 8))); +#else + tcg_gen_ld_tl(t, cpu_env, offsetof(CPUX86State, xmm_t0.ZMM_L((vec_len - 1) / 4))); +#endif + + tcg_gen_extract2_tl(s->T0, t, s->T0, TARGET_LONG_BITS - 8); + } else { + /* + * The _previous_ value is deposited into bits 8 and higher of t. Because + * those bits are known to be zero after ld8u, this becomes a shift+or + * if deposit is not available. + */ + tcg_gen_ld8u_tl(t, cpu_env, offsetof(CPUX86State, xmm_t0.ZMM_B(vec_len - 1))); + tcg_gen_deposit_tl(s->T0, t, s->T0, 8, TARGET_LONG_BITS - 8); + } } - tcg_gen_extu_i32_tl(s->T0, s->tmp2_i32); + tcg_temp_free(t); } static void gen_PSHUFW(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode) |