[PATCH 0/5] x86/Intel: AVX512 syntax enhancements

[Cui, Lili]

> -----Original Message-----
> From: Binutils <binutils-bounces+lili.cui=intel.com@sourceware.org> On
> Behalf Of Jan Beulich via Binutils
> Sent: Wednesday, May 4, 2022 7:45 PM
> To: Binutils <binutils@sourceware.org>
> Subject: [PATCH 0/5] x86/Intel: AVX512 syntax enhancements
> 
> As pointed out long ago already, what gas accepts and what objdump emits
> isn't in line with the SDM. Finally I also happened to find mention of this in
> MASM documentation [1]. This series extends (gas) and converts (objdump)
> respective support. As a nice side effect, a few hundred insn templates go
> away from the opcode table.
> 
> 1: Intel: adjust representation of embedded broadcast
> 2: Intel: allow MASM representation of embedded broadcast
> 3: Intel: adjust representation of embedded rounding / SAE
> 4: re-work AVX512 embedded rounding / SAE
> 5: Intel: allow MASM representation of embedded rounding / SAE
> 

Hi Jan, 
I reviewed all the patches in this patch set, I have only one doubt, the others look good.

1. If we use BCST instead {1to*}, it cannot directly reflect the broadcast number. When the register size is zmm, but broadcast number is not the same.

-[      ]*[a-f0-9]+:[   ]*62 f5 54 58 58 31[     ]*vaddph zmm6,zmm5,WORD PTR \[ecx\]\{1to32\}
+[      ]*[a-f0-9]+:[   ]*62 f5 54 58 58 31[     ]*vaddph zmm6,zmm5,WORD BCST \[ecx\]

-[      ]*[a-f0-9]+:[   ]*62 65 7d df 5b 72 80[          ]*vcvtph2dq zmm30\{k7\}\{z\},WORD PTR \[rdx-0x100\]\{1to16\}
+[      ]*[a-f0-9]+:[   ]*62 65 7d df 5b 72 80[          ]*vcvtph2dq zmm30\{k7\}\{z\},WORD BCST \[rdx-0x100\]

2. Just remove the last comma, it's ok for me, I remember FP16 has an instruction with {sae} on the middle position for the ATT format. But the intel format is placed at the end, I don't know if there is any problem.

-[      ]*[a-f0-9]+:[   ]*62 f5 54 18 58 f4[     ]*vaddph zmm6,zmm5,zmm4,\{rn-sae\}
+[      ]*[a-f0-9]+:[   ]*62 f5 54 18 58 f4[     ]*vaddph zmm6,zmm5,zmm4\{rn-sae\}

FP16:
vcvtusi2sh %edx, {rn-sae}, %xmm29, %xmm30
vcvtusi2sh xmm6,xmm5,edx\{rn-sae\}

3. This can reduce the  templates size, it is good to me.

-vsubsh, 0xf35c, None, CpuAVX512_FP16, Modrm|EVexLIG|Masking=3|EVexMap5|VexVVVV|VexW0|Disp8MemShift=1|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { RegXMM|Word|Unspecified|BaseIndex, RegXMM, RegXMM }
-vsubsh, 0xf35c, None, CpuAVX512_FP16, Modrm|EVexLIG|Masking=3|EVexMap5|VexVVVV|VexW0|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|StaticRounding|SAE, { Imm8, RegXMM, RegXMM, RegXMM }

+vsubsh, 0xf35c, None, CpuAVX512_FP16, Modrm|EVexLIG|Masking=3|EVexMap5|VexVVVV|VexW0|Disp8MemShift=1|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|StaticRounding|SAE, { RegXMM|Word|Unspecified|BaseIndex, RegXMM, RegXMM }


Thanks,
Lili.

> Jan
> 
> [1] https://docs.microsoft.com/en-us/cpp/assembler/masm/instruction-
> format?view=msvc-170