Attempt to handle MRMInitReg in emitVEXOpcodePrefix. Hopefully fixes PR12711.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155896 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp
index 79404da..09524fe 100644
--- a/lib/Target/X86/X86CodeEmitter.cpp
+++ b/lib/Target/X86/X86CodeEmitter.cpp
@@ -939,7 +939,18 @@
// Classify VEX_B, VEX_4V, VEX_R, VEX_X
unsigned CurOp = 0;
switch (TSFlags & X86II::FormMask) {
- case X86II::MRMInitReg: llvm_unreachable("FIXME: Remove this!");
+ case X86II::MRMInitReg:
+ // Duplicate register.
+ if (X86II::isX86_64ExtendedReg(MI.getOperand(CurOp).getReg()))
+ VEX_R = 0x0;
+
+ if (HasVEX_4V)
+ VEX_4V = getVEXRegisterEncoding(MI, CurOp);
+ if (X86II::isX86_64ExtendedReg(MI.getOperand(CurOp).getReg()))
+ VEX_B = 0x0;
+ if (HasVEX_4VOp3)
+ VEX_4V = getVEXRegisterEncoding(MI, CurOp);
+ break;
case X86II::MRMDestMem: {
// MRMDestMem instructions forms:
// MemAddr, src1(ModR/M)