For PR950:
This patch converts the old SHR instruction into two instructions,
AShr (Arithmetic) and LShr (Logical). The Shr instructions now are not
dependent on the sign of their operands.
llvm-svn: 31542
diff --git a/llvm/lib/VMCore/Constants.cpp b/llvm/lib/VMCore/Constants.cpp
index bcfd387..ee855ca 100644
--- a/llvm/lib/VMCore/Constants.cpp
+++ b/llvm/lib/VMCore/Constants.cpp
@@ -498,20 +498,11 @@
Constant *ConstantExpr::getShl(Constant *C1, Constant *C2) {
return get(Instruction::Shl, C1, C2);
}
-Constant *ConstantExpr::getShr(Constant *C1, Constant *C2) {
- return get(Instruction::Shr, C1, C2);
+Constant *ConstantExpr::getLShr(Constant *C1, Constant *C2) {
+ return get(Instruction::LShr, C1, C2);
}
-
-Constant *ConstantExpr::getUShr(Constant *C1, Constant *C2) {
- if (C1->getType()->isUnsigned()) return getShr(C1, C2);
- return getCast(getShr(getCast(C1,
- C1->getType()->getUnsignedVersion()), C2), C1->getType());
-}
-
-Constant *ConstantExpr::getSShr(Constant *C1, Constant *C2) {
- if (C1->getType()->isSigned()) return getShr(C1, C2);
- return getCast(getShr(getCast(C1,
- C1->getType()->getSignedVersion()), C2), C1->getType());
+Constant *ConstantExpr::getAShr(Constant *C1, Constant *C2) {
+ return get(Instruction::AShr, C1, C2);
}
/// getWithOperandReplaced - Return a constant expression identical to this
@@ -1330,7 +1321,9 @@
return new UnaryConstantExpr(Instruction::Cast, V.second[0], Ty);
if ((V.first >= Instruction::BinaryOpsBegin &&
V.first < Instruction::BinaryOpsEnd) ||
- V.first == Instruction::Shl || V.first == Instruction::Shr)
+ V.first == Instruction::Shl ||
+ V.first == Instruction::LShr ||
+ V.first == Instruction::AShr)
return new BinaryConstantExpr(V.first, V.second[0], V.second[1]);
if (V.first == Instruction::Select)
return new SelectConstantExpr(V.second[0], V.second[1], V.second[2]);
@@ -1364,7 +1357,8 @@
OldC->getOperand(2));
break;
case Instruction::Shl:
- case Instruction::Shr:
+ case Instruction::LShr:
+ case Instruction::AShr:
New = ConstantExpr::getShiftTy(NewTy, OldC->getOpcode(),
OldC->getOperand(0), OldC->getOperand(1));
break;
@@ -1453,7 +1447,8 @@
Constant *ConstantExpr::getTy(const Type *ReqTy, unsigned Opcode,
Constant *C1, Constant *C2) {
- if (Opcode == Instruction::Shl || Opcode == Instruction::Shr)
+ if (Opcode == Instruction::Shl || Opcode == Instruction::LShr ||
+ Opcode == Instruction::AShr)
return getShiftTy(ReqTy, Opcode, C1, C2);
// Check the operands for consistency first
assert(Opcode >= Instruction::BinaryOpsBegin &&
@@ -1521,9 +1516,10 @@
assert(C1->getType() == C2->getType() && "Op types should be identical!");
break;
case Instruction::Shl:
- case Instruction::Shr:
+ case Instruction::LShr:
+ case Instruction::AShr:
assert(C2->getType() == Type::UByteTy && "Shift should be by ubyte!");
- assert((C1->getType()->isInteger() || isa<PackedType>(C1->getType())) &&
+ assert(C1->getType()->isInteger() &&
"Tried to create a shift operation on a non-integer type!");
break;
default:
@@ -1558,8 +1554,9 @@
Constant *ConstantExpr::getShiftTy(const Type *ReqTy, unsigned Opcode,
Constant *C1, Constant *C2) {
// Check the operands for consistency first
- assert((Opcode == Instruction::Shl ||
- Opcode == Instruction::Shr) &&
+ assert((Opcode == Instruction::Shl ||
+ Opcode == Instruction::LShr ||
+ Opcode == Instruction::AShr) &&
"Invalid opcode in binary constant expression");
assert(C1->getType()->isIntegral() && C2->getType() == Type::UByteTy &&
"Invalid operand types for Shift constant expr!");