1. merge fast-isel-shift-imm.ll into fast-isel-x86-64.ll

2. implement rdar://9289501 - fast isel should fold trivial multiplies to shifts
3. teach tblgen to handle shift immediates that are different sizes than the 
   shifted operands, eliminating some code from the X86 fast isel backend.
4. Have FastISel::SelectBinaryOp use (the poorly named) FastEmit_ri_ function
   instead of FastEmit_ri to simplify code.

llvm-svn: 129666

1 files changed, 13 insertions, 22 deletions

diff --git a/llvm/lib/Target/X86/X86FastISel.cpp b/llvm/lib/Target/X86/X86FastISel.cpp
index 8aa2a72e4e5..7be7f18e985 100644
--- a/llvm/lib/Target/X86/X86FastISel.cpp
+++ b/llvm/lib/Target/X86/X86FastISel.cpp
@@ -1084,42 +1084,42 @@ bool X86FastISel::X86SelectBranch(const Instruction *I) {
 }
 
 bool X86FastISel::X86SelectShift(const Instruction *I) {
-  unsigned CReg = 0, OpReg = 0, OpImm = 0;
+  unsigned CReg = 0, OpReg = 0;
   const TargetRegisterClass *RC = NULL;
   if (I->getType()->isIntegerTy(8)) {
     CReg = X86::CL;
     RC = &X86::GR8RegClass;
     switch (I->getOpcode()) {
-    case Instruction::LShr: OpReg = X86::SHR8rCL; OpImm = X86::SHR8ri; break;
-    case Instruction::AShr: OpReg = X86::SAR8rCL; OpImm = X86::SAR8ri; break;
-    case Instruction::Shl:  OpReg = X86::SHL8rCL; OpImm = X86::SHL8ri; break;
+    case Instruction::LShr: OpReg = X86::SHR8rCL; break;
+    case Instruction::AShr: OpReg = X86::SAR8rCL; break;
+    case Instruction::Shl:  OpReg = X86::SHL8rCL; break;
     default: return false;
     }
   } else if (I->getType()->isIntegerTy(16)) {
     CReg = X86::CX;
     RC = &X86::GR16RegClass;
     switch (I->getOpcode()) {
-    case Instruction::LShr: OpReg = X86::SHR16rCL; OpImm = X86::SHR16ri; break;
-    case Instruction::AShr: OpReg = X86::SAR16rCL; OpImm = X86::SAR16ri; break;
-    case Instruction::Shl:  OpReg = X86::SHL16rCL; OpImm = X86::SHL16ri; break;
+    case Instruction::LShr: OpReg = X86::SHR16rCL; break;
+    case Instruction::AShr: OpReg = X86::SAR16rCL; break;
+    case Instruction::Shl:  OpReg = X86::SHL16rCL; break;
     default: return false;
     }
   } else if (I->getType()->isIntegerTy(32)) {
     CReg = X86::ECX;
     RC = &X86::GR32RegClass;
     switch (I->getOpcode()) {
-    case Instruction::LShr: OpReg = X86::SHR32rCL; OpImm = X86::SHR32ri; break;
-    case Instruction::AShr: OpReg = X86::SAR32rCL; OpImm = X86::SAR32ri; break;
-    case Instruction::Shl:  OpReg = X86::SHL32rCL; OpImm = X86::SHL32ri; break;
+    case Instruction::LShr: OpReg = X86::SHR32rCL; break;
+    case Instruction::AShr: OpReg = X86::SAR32rCL; break;
+    case Instruction::Shl:  OpReg = X86::SHL32rCL; break;
     default: return false;
     }
   } else if (I->getType()->isIntegerTy(64)) {
     CReg = X86::RCX;
     RC = &X86::GR64RegClass;
     switch (I->getOpcode()) {
-    case Instruction::LShr: OpReg = X86::SHR64rCL; OpImm = X86::SHR64ri; break;
-    case Instruction::AShr: OpReg = X86::SAR64rCL; OpImm = X86::SAR64ri; break;
-    case Instruction::Shl:  OpReg = X86::SHL64rCL; OpImm = X86::SHL64ri; break;
+    case Instruction::LShr: OpReg = X86::SHR64rCL; break;
+    case Instruction::AShr: OpReg = X86::SAR64rCL; break;
+    case Instruction::Shl:  OpReg = X86::SHL64rCL; break;
     default: return false;
     }
   } else {
@@ -1133,15 +1133,6 @@ bool X86FastISel::X86SelectShift(const Instruction *I) {
   unsigned Op0Reg = getRegForValue(I->getOperand(0));
   if (Op0Reg == 0) return false;
 
-  // Fold immediate in shl(x,3).
-  if (const ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
-    unsigned ResultReg = createResultReg(RC);
-    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(OpImm),
-            ResultReg).addReg(Op0Reg).addImm(CI->getZExtValue() & 0xff);
-    UpdateValueMap(I, ResultReg);
-    return true;
-  }
-
   unsigned Op1Reg = getRegForValue(I->getOperand(1));
   if (Op1Reg == 0) return false;
   BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),