[llvm-commits] CVS: llvm/lib/Transforms/Scalar/SCCP.cpp
Chris Lattner
lattner at cs.uiuc.edu
Tue Apr 13 14:44:07 PDT 2004
Changes in directory llvm/lib/Transforms/Scalar:
SCCP.cpp updated: 1.93 -> 1.94
---
Log message:
Add SCCP support for constant folding calls, implementing:
test/Regression/Transforms/SCCP/calltest.ll
---
Diffs of the changes: (+33 -1)
Index: llvm/lib/Transforms/Scalar/SCCP.cpp
diff -u llvm/lib/Transforms/Scalar/SCCP.cpp:1.93 llvm/lib/Transforms/Scalar/SCCP.cpp:1.94
--- llvm/lib/Transforms/Scalar/SCCP.cpp:1.93 Sun Apr 4 20:29:05 2004
+++ llvm/lib/Transforms/Scalar/SCCP.cpp Tue Apr 13 14:43:54 2004
@@ -29,6 +29,7 @@
#include "llvm/Pass.h"
#include "llvm/Type.h"
#include "llvm/Support/InstVisitor.h"
+#include "llvm/Transforms/Utils/Local.h"
#include "Support/Debug.h"
#include "Support/Statistic.h"
#include "Support/STLExtras.h"
@@ -220,7 +221,7 @@
void visitStoreInst (Instruction &I) { /*returns void*/ }
void visitLoadInst (LoadInst &I);
void visitGetElementPtrInst(GetElementPtrInst &I);
- void visitCallInst (Instruction &I) { markOverdefined(&I); }
+ void visitCallInst (CallInst &I);
void visitInvokeInst (TerminatorInst &I) {
if (I.getType() != Type::VoidTy) markOverdefined(&I);
visitTerminatorInst(I);
@@ -776,4 +777,35 @@
// Otherwise we cannot say for certain what value this load will produce.
// Bail out.
markOverdefined(IV, &I);
+}
+
+void SCCP::visitCallInst(CallInst &I) {
+ InstVal &IV = ValueState[&I];
+ if (IV.isOverdefined()) return;
+
+ Function *F = I.getCalledFunction();
+ if (F == 0 || !canConstantFoldCallTo(F)) {
+ markOverdefined(IV, &I);
+ return;
+ }
+
+ std::vector<Constant*> Operands;
+ Operands.reserve(I.getNumOperands()-1);
+
+ for (unsigned i = 1, e = I.getNumOperands(); i != e; ++i) {
+ InstVal &State = getValueState(I.getOperand(i));
+ if (State.isUndefined())
+ return; // Operands are not resolved yet...
+ else if (State.isOverdefined()) {
+ markOverdefined(IV, &I);
+ return;
+ }
+ assert(State.isConstant() && "Unknown state!");
+ Operands.push_back(State.getConstant());
+ }
+
+ if (Constant *C = ConstantFoldCall(F, Operands))
+ markConstant(IV, &I, C);
+ else
+ markOverdefined(IV, &I);
}
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