[llvm] [X86][MC] Support decoding of EGPR for APX (PR #72102)

[Phoebe Wang via llvm-commits]

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@@ -33,13 +33,24 @@ namespace X86Disassembler {
 #define xFromREX(rex)        (((rex) & 0x2) >> 1)
 #define bFromREX(rex)        ((rex) & 0x1)
 
+#define mFromREX2(rex2) (((rex2) >> 7) & 0x1)
+#define r2FromREX2(rex2) (((rex2) >> 6) & 0x1)
+#define x2FromREX2(rex2) (((rex2) >> 5) & 0x1)
+#define b2FromREX2(rex2) (((rex2) >> 4) & 0x1)
+#define wFromREX2(rex2) (((rex2) >> 3) & 0x1)
+#define rFromREX2(rex2) (((rex2) >> 2) & 0x1)
+#define xFromREX2(rex2) (((rex2) >> 1) & 0x1)
+#define bFromREX2(rex2) ((rex2) & 0x1)
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phoebewang wrote:

Align with the code around, and use & 0xXX >> X format to align.

https://github.com/llvm/llvm-project/pull/72102