[llvm] [X86][MC] Support Enc/Dec for EGPR for promoted SHA instruction (PR #75582)

[Phoebe Wang via llvm-commits]

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@@ -0,0 +1,10 @@
+
+# RUN: llvm-mc -triple x86_64 -x86-asm-syntax=intel -output-asm-variant=1 --show-encoding %s | FileCheck %s
+
+# CHECK: sha256rnds2	xmm12, xmm13, xmm0
+# CHECK: encoding: [0x45,0x0f,0x38,0xcb,0xe5]
+         sha256rnds2	xmm12, xmm13, xmm0
+
+# CHECK: sha256rnds2	xmm12, xmmword ptr [r28 + 4*r29 + 291], xmm0
+# CHECK: encoding: [0x62,0x1c,0x78,0x08,0xdb,0xa4,0xac,0x23,0x01,0x00,0x00]
+         sha256rnds2	xmm12, xmmword ptr [r28 + 4*r29 + 291], xmm0
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phoebewang wrote:

ditto.

https://github.com/llvm/llvm-project/pull/75582