Enable rematerialization of constants using AliasAnalysis::pointsToConstantMemory,
and knowledge of PseudoSourceValues. This unfortunately isn't sufficient to allow
constants to be rematerialized in PIC mode -- the extra indirection is a
complication.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54000 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PseudoSourceValue.cpp b/lib/CodeGen/PseudoSourceValue.cpp
index 2799554..bcf4ea8 100644
--- a/lib/CodeGen/PseudoSourceValue.cpp
+++ b/lib/CodeGen/PseudoSourceValue.cpp
@@ -11,6 +11,7 @@
//
//===----------------------------------------------------------------------===//
+#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Support/Compiler.h"
@@ -51,6 +52,9 @@
const int FI;
public:
explicit FixedStackPseudoSourceValue(int fi) : FI(fi) {}
+
+ virtual bool isConstant(const MachineFrameInfo *MFI) const;
+
virtual void print(std::ostream &OS) const {
OS << "FixedStack" << FI;
}
@@ -64,4 +68,20 @@
V = new FixedStackPseudoSourceValue(FI);
return V;
}
+
+ bool PseudoSourceValue::isConstant(const MachineFrameInfo *) const {
+ if (this == getStack())
+ return false;
+ if (this == getGOT() ||
+ this == getConstantPool() ||
+ this == getJumpTable())
+ return true;
+ assert(0 && "Unknown PseudoSourceValue!");
+ return false;
+ }
+
+ bool
+ FixedStackPseudoSourceValue::isConstant(const MachineFrameInfo *MFI) const {
+ return MFI && MFI->isImmutableObjectIndex(FI);
+ }
}