[llvm] [X86][MC] Support Enc/Dec for EGPR for promoted CRC32 (PR #76434)

[via llvm-commits]

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@@ -6698,6 +6698,30 @@ let Constraints = "$src1 = $dst" in {
     def CRC32r64r8 : SS42I_crc32r<0xF0, "crc32{b}", GR64, GR8,
                                    null_frag>, REX_W;
   }
+
+  def CRC32r32m8_EVEX  : SS42I_crc32m<0xF0, "crc32{b}", GR32, i8mem,
+                                      int_x86_sse42_crc32_32_8>, EVEX, T_MAP4, PS;
+  def CRC32r32r8_EVEX  : SS42I_crc32r<0xF0, "crc32{b}", GR32, GR8,
+                                      int_x86_sse42_crc32_32_8>, EVEX, T_MAP4, PS;
+  def CRC32r32m16_EVEX : SS42I_crc32m<0xF1, "crc32{w}", GR32, i16mem,
+                                      int_x86_sse42_crc32_32_16>, EVEX, T_MAP4, PD;
+  def CRC32r32r16_EVEX : SS42I_crc32r<0xF1, "crc32{w}", GR32, GR16,
+                                      int_x86_sse42_crc32_32_16>, EVEX, T_MAP4, PD;
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XinWang10 wrote:

EVEX encoding would set CD8_Scale by default, which could interfere compiler when encoding disp8, like 
crc32w 123(%r28,%r29,4), %r18d, we expect compiler could encode the 123 in one byte, but if we have non-zero CD8_Scare, we still need 4 bytes.

https://github.com/llvm/llvm-project/pull/76434