From fab01c190883724f92111e5bdb4d4d82748284eb Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper@gmail.com>
Date: Thu, 16 Jan 2014 06:14:45 +0000
Subject: [PATCH] Remove use of OpSize for populating VEX_PP field. A prefix
 encoding is now used instead. Simplify some other code. No functional changes
 intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199353 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp | 14 ++++----------
 lib/Target/X86/X86CodeEmitter.cpp                | 14 ++++----------
 2 files changed, 8 insertions(+), 20 deletions(-)

diff --git a/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp b/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
index bd3c00626d6..55a89329261 100644
--- a/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
@@ -634,7 +634,7 @@ void X86MCCodeEmitter::EmitVEXOpcodePrefix(uint64_t TSFlags, unsigned &CurByte,
   unsigned char VEX_W = 0;
 
   // XOP: Use XOP prefix byte 0x8f instead of VEX.
-  bool XOP = false;
+  bool XOP = (TSFlags >> X86II::VEXShift) & X86II::XOP;
 
   // VEX_5M (VEX m-mmmmm field):
   //
@@ -688,16 +688,9 @@ void X86MCCodeEmitter::EmitVEXOpcodePrefix(uint64_t TSFlags, unsigned &CurByte,
 
   bool EncodeRC = false;
 
-  // Encode the operand size opcode prefix as needed.
-  if (TSFlags & X86II::OpSize)
-    VEX_PP = 0x01;
-
   if ((TSFlags >> X86II::VEXShift) & X86II::VEX_W)
     VEX_W = 1;
 
-  if ((TSFlags >> X86II::VEXShift) & X86II::XOP)
-    XOP = true;
-
   if ((TSFlags >> X86II::VEXShift) & X86II::VEX_L)
     VEX_L = 1;
   if (HasEVEX && ((TSFlags >> X86II::VEXShift) & X86II::EVEX_L2))
@@ -780,6 +773,9 @@ void X86MCCodeEmitter::EmitVEXOpcodePrefix(uint64_t TSFlags, unsigned &CurByte,
     ++CurOp;
 
   switch (TSFlags & X86II::FormMask) {
+  default: llvm_unreachable("Unexpected form in EmitVEXOpcodePrefix!");
+  case X86II::RawFrm:
+    break;
   case X86II::MRMDestMem: {
     // MRMDestMem instructions forms:
     //  MemAddr, src1(ModR/M)
@@ -978,8 +974,6 @@ void X86MCCodeEmitter::EmitVEXOpcodePrefix(uint64_t TSFlags, unsigned &CurByte,
     if (HasEVEX && X86II::is32ExtendedReg(MI.getOperand(CurOp).getReg()))
       VEX_X = 0x0;
     break;
-  default: // RawFrm
-    break;
   }
 
   // Emit segment override opcode prefix as needed.
diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp
index 5dba4ecbfdb..a699d67919f 100644
--- a/lib/Target/X86/X86CodeEmitter.cpp
+++ b/lib/Target/X86/X86CodeEmitter.cpp
@@ -834,7 +834,7 @@ void Emitter<CodeEmitter>::emitVEXOpcodePrefix(uint64_t TSFlags,
   unsigned char VEX_W = 0;
 
   // XOP: Use XOP prefix byte 0x8f instead of VEX.
-  bool XOP = false;
+  bool XOP = (TSFlags >> X86II::VEXShift) & X86II::XOP;
 
   // VEX_5M (VEX m-mmmmm field):
   //
@@ -869,16 +869,9 @@ void Emitter<CodeEmitter>::emitVEXOpcodePrefix(uint64_t TSFlags,
   //
   unsigned char VEX_PP = 0;
 
-  // Encode the operand size opcode prefix as needed.
-  if (TSFlags & X86II::OpSize)
-    VEX_PP = 0x01;
-
   if ((TSFlags >> X86II::VEXShift) & X86II::VEX_W)
     VEX_W = 1;
 
-  if ((TSFlags >> X86II::VEXShift) & X86II::XOP)
-    XOP = true;
-
   if ((TSFlags >> X86II::VEXShift) & X86II::VEX_L)
     VEX_L = 1;
 
@@ -946,6 +939,9 @@ void Emitter<CodeEmitter>::emitVEXOpcodePrefix(uint64_t TSFlags,
   }
 
   switch (TSFlags & X86II::FormMask) {
+    default: llvm_unreachable("Unexpected form in emitVEXOpcodePrefix!");
+    case X86II::RawFrm:
+      break;
     case X86II::MRMDestMem: {
       // MRMDestMem instructions forms:
       //  MemAddr, src1(ModR/M)
@@ -1062,8 +1058,6 @@ void Emitter<CodeEmitter>::emitVEXOpcodePrefix(uint64_t TSFlags,
       if (X86II::isX86_64ExtendedReg(MI.getOperand(CurOp).getReg()))
         VEX_B = 0x0;
       break;
-    default: // RawFrm
-      break;
   }
 
   // Emit segment override opcode prefix as needed.