[llvm-commits] [llvm] r67638 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/ptr-int-cast.ll
Chris Lattner
sabre at nondot.org
Tue Mar 24 11:35:40 PDT 2009
Author: lattner
Date: Tue Mar 24 13:35:40 2009
New Revision: 67638
URL: http://llvm.org/viewvc/llvm-project?rev=67638&view=rev
Log:
canonicalize inttoptr and ptrtoint instructions which cast pointers
to/from integer types that are not intptr_t to convert to intptr_t
then do an integer conversion to the dest type. This exposes the
cast to the optimizer.
Added:
llvm/trunk/test/Transforms/InstCombine/ptr-int-cast.ll
Modified:
llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=67638&r1=67637&r2=67638&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Tue Mar 24 13:35:40 2009
@@ -218,7 +218,7 @@
Instruction *visitFPToSI(FPToSIInst &FI);
Instruction *visitUIToFP(CastInst &CI);
Instruction *visitSIToFP(CastInst &CI);
- Instruction *visitPtrToInt(CastInst &CI);
+ Instruction *visitPtrToInt(PtrToIntInst &CI);
Instruction *visitIntToPtr(IntToPtrInst &CI);
Instruction *visitBitCast(BitCastInst &CI);
Instruction *FoldSelectOpOp(SelectInst &SI, Instruction *TI,
@@ -474,9 +474,16 @@
Instruction::CastOps firstOp = Instruction::CastOps(CI->getOpcode());
Instruction::CastOps secondOp = Instruction::CastOps(opcode);
- return Instruction::CastOps(
- CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy,
- DstTy, TD->getIntPtrType()));
+ unsigned Res = CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy,
+ DstTy, TD->getIntPtrType());
+
+ // We don't want to form an inttoptr or ptrtoint that converts to an integer
+ // type that differs from the pointer size.
+ if ((Res == Instruction::IntToPtr && SrcTy != TD->getIntPtrType()) ||
+ (Res == Instruction::PtrToInt && DstTy != TD->getIntPtrType()))
+ Res = 0;
+
+ return Instruction::CastOps(Res);
}
/// ValueRequiresCast - Return true if the cast from "V to Ty" actually results
@@ -8536,11 +8543,36 @@
return commonCastTransforms(CI);
}
-Instruction *InstCombiner::visitPtrToInt(CastInst &CI) {
+Instruction *InstCombiner::visitPtrToInt(PtrToIntInst &CI) {
+ // If the destination integer type is smaller than the intptr_t type for
+ // this target, do a ptrtoint to intptr_t then do a trunc. This allows the
+ // trunc to be exposed to other transforms. Don't do this for extending
+ // ptrtoint's, because we don't know if the target sign or zero extends its
+ // pointers.
+ if (CI.getType()->getPrimitiveSizeInBits() < TD->getPointerSizeInBits()) {
+ Value *P = InsertNewInstBefore(new PtrToIntInst(CI.getOperand(0),
+ TD->getIntPtrType(),
+ "tmp"), CI);
+ return new TruncInst(P, CI.getType());
+ }
+
return commonPointerCastTransforms(CI);
}
Instruction *InstCombiner::visitIntToPtr(IntToPtrInst &CI) {
+ // If the source integer type is larger than the intptr_t type for
+ // this target, do a trunc to the intptr_t type, then inttoptr of it. This
+ // allows the trunc to be exposed to other transforms. Don't do this for
+ // extending inttoptr's, because we don't know if the target sign or zero
+ // extends to pointers.
+ if (CI.getOperand(0)->getType()->getPrimitiveSizeInBits() >
+ TD->getPointerSizeInBits()) {
+ Value *P = InsertNewInstBefore(new TruncInst(CI.getOperand(0),
+ TD->getIntPtrType(),
+ "tmp"), CI);
+ return new IntToPtrInst(P, CI.getType());
+ }
+
if (Instruction *I = commonCastTransforms(CI))
return I;
Added: llvm/trunk/test/Transforms/InstCombine/ptr-int-cast.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/ptr-int-cast.ll?rev=67638&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/ptr-int-cast.ll (added)
+++ llvm/trunk/test/Transforms/InstCombine/ptr-int-cast.ll Tue Mar 24 13:35:40 2009
@@ -0,0 +1,16 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis > %t
+
+define i1 @test1(i32 *%x) nounwind {
+entry:
+; RUN: grep {ptrtoint i32\\* %x to i64} %t
+ %tmp = ptrtoint i32* %x to i1
+ ret i1 %tmp
+}
+
+define i32* @test2(i128 %x) nounwind {
+entry:
+; RUN: grep {inttoptr i64 %.mp1 to i32\\*} %t
+ %tmp = inttoptr i128 %x to i32*
+ ret i32* %tmp
+}
+
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