Add Constant Hoisting Pass

Retry commit r200022 with a fix for the build bot errors. Constant expressions
have (unlike instructions) module scope use lists and therefore may have users
in different functions. The fix is to simply ignore these out-of-function uses.

llvm-svn: 200034

1 files changed, 95 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index da2b021da93..781be2fddd9 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -18,6 +18,7 @@
 #include "X86.h"
 #include "X86TargetMachine.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/IntrinsicInst.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Target/CostTable.h"
 #include "llvm/Target/TargetLowering.h"
@@ -107,6 +108,14 @@ public:
   virtual unsigned getReductionCost(unsigned Opcode, Type *Ty,
                                     bool IsPairwiseForm) const LLVM_OVERRIDE;
 
+  virtual unsigned getIntImmCost(const APInt &Imm,
+                                 Type *Ty) const LLVM_OVERRIDE;
+
+  virtual unsigned getIntImmCost(unsigned Opcode, const APInt &Imm,
+                                 Type *Ty) const LLVM_OVERRIDE;
+  virtual unsigned getIntImmCost(Intrinsic::ID IID, const APInt &Imm,
+                                 Type *Ty) const LLVM_OVERRIDE;
+
   /// @}
 };
 
@@ -694,3 +703,89 @@ unsigned X86TTI::getReductionCost(unsigned Opcode, Type *ValTy,
   return TargetTransformInfo::getReductionCost(Opcode, ValTy, IsPairwise);
 }
 
+unsigned X86TTI::getIntImmCost(const APInt &Imm, Type *Ty) const {
+  assert(Ty->isIntegerTy());
+
+  unsigned BitSize = Ty->getPrimitiveSizeInBits();
+  if (BitSize == 0)
+    return ~0U;
+
+  if (Imm.getBitWidth() <= 64 &&
+      (isInt<32>(Imm.getSExtValue()) || isUInt<32>(Imm.getZExtValue())))
+    return TCC_Basic;
+  else
+    return 2 * TCC_Basic;
+}
+
+unsigned X86TTI::getIntImmCost(unsigned Opcode, const APInt &Imm,
+                               Type *Ty) const {
+  assert(Ty->isIntegerTy());
+
+  unsigned BitSize = Ty->getPrimitiveSizeInBits();
+  if (BitSize == 0)
+    return ~0U;
+
+  switch (Opcode) {
+  case Instruction::Add:
+  case Instruction::Sub:
+  case Instruction::Mul:
+  case Instruction::UDiv:
+  case Instruction::SDiv:
+  case Instruction::URem:
+  case Instruction::SRem:
+  case Instruction::Shl:
+  case Instruction::LShr:
+  case Instruction::AShr:
+  case Instruction::And:
+  case Instruction::Or:
+  case Instruction::Xor:
+  case Instruction::ICmp:
+    if (Imm.getBitWidth() <= 64 && isInt<32>(Imm.getSExtValue()))
+      return TCC_Free;
+    else
+      return X86TTI::getIntImmCost(Imm, Ty);
+  case Instruction::Trunc:
+  case Instruction::ZExt:
+  case Instruction::SExt:
+  case Instruction::IntToPtr:
+  case Instruction::PtrToInt:
+  case Instruction::BitCast:
+  case Instruction::Call:
+  case Instruction::Select:
+  case Instruction::Ret:
+  case Instruction::Load:
+  case Instruction::Store:
+    return X86TTI::getIntImmCost(Imm, Ty);
+  }
+  return TargetTransformInfo::getIntImmCost(Opcode, Imm, Ty);
+}
+
+unsigned X86TTI::getIntImmCost(Intrinsic::ID IID, const APInt &Imm,
+                               Type *Ty) const {
+  assert(Ty->isIntegerTy());
+
+  unsigned BitSize = Ty->getPrimitiveSizeInBits();
+  if (BitSize == 0)
+    return ~0U;
+
+  switch (IID) {
+  default: return TargetTransformInfo::getIntImmCost(IID, Imm, Ty);
+  case Intrinsic::sadd_with_overflow:
+  case Intrinsic::uadd_with_overflow:
+  case Intrinsic::ssub_with_overflow:
+  case Intrinsic::usub_with_overflow:
+  case Intrinsic::smul_with_overflow:
+  case Intrinsic::umul_with_overflow:
+    if (Imm.getBitWidth() <= 64 && isInt<32>(Imm.getSExtValue()))
+      return TCC_Free;
+    else
+      return X86TTI::getIntImmCost(Imm, Ty);
+  case Intrinsic::experimental_stackmap:
+  case Intrinsic::experimental_patchpoint_void:
+  case Intrinsic::experimental_patchpoint_i64:
+    if (Imm.getBitWidth() <= 64 && isInt<64>(Imm.getSExtValue()))
+      return TCC_Free;
+    else
+      return X86TTI::getIntImmCost(Imm, Ty);
+  }
+}