Shrink the size of AllocationInst by using its SubclassData
field to store the alignment value instead of haing a
separate field.
llvm-svn: 48727
diff --git a/llvm/lib/VMCore/Instructions.cpp b/llvm/lib/VMCore/Instructions.cpp
index df5a2fc..33ab1c6 100644
--- a/llvm/lib/VMCore/Instructions.cpp
+++ b/llvm/lib/VMCore/Instructions.cpp
@@ -677,8 +677,8 @@
unsigned Align, const std::string &Name,
Instruction *InsertBefore)
: UnaryInstruction(PointerType::getUnqual(Ty), iTy, getAISize(ArraySize),
- InsertBefore), Alignment(Align) {
- assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
+ InsertBefore) {
+ setAlignment(Align);
assert(Ty != Type::VoidTy && "Cannot allocate void!");
setName(Name);
}
@@ -687,8 +687,8 @@
unsigned Align, const std::string &Name,
BasicBlock *InsertAtEnd)
: UnaryInstruction(PointerType::getUnqual(Ty), iTy, getAISize(ArraySize),
- InsertAtEnd), Alignment(Align) {
- assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
+ InsertAtEnd) {
+ setAlignment(Align);
assert(Ty != Type::VoidTy && "Cannot allocate void!");
setName(Name);
}
@@ -697,6 +697,12 @@
AllocationInst::~AllocationInst() {
}
+void AllocationInst::setAlignment(unsigned Align) {
+ assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
+ SubclassData = Log2_32(Align) + 1;
+ assert(getAlignment() == Align && "Alignment representation error!");
+}
+
bool AllocationInst::isArrayAllocation() const {
if (ConstantInt *CI = dyn_cast<ConstantInt>(getOperand(0)))
return CI->getZExtValue() != 1;