6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-03-20 11:32:33 +00:00
Code Issues Projects Releases Wiki Activity

Add SCCP support for constant folding calls, implementing:

Browse Source 
test/Regression/Transforms/SCCP/calltest.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12921 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2004-04-13 19:43:54 +00:00
parent 3d78b23d24
commit 58b7b08ad7
1 changed files with 33 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
lib/Transforms/Scalar/SCCP.cpp
View File

@ -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 @@ private:
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);
@ -777,3 +778,34 @@ void SCCP::visitLoadInst(LoadInst &I) {
// 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);
}