[llvm] r190859 - Bugfix for PR17099:

[Stepan Dyatkovskiy]

Author: dyatkovskiy
Date: Tue Sep 17 04:36:11 2013
New Revision: 190859

URL: http://llvm.org/viewvc/llvm-project?rev=190859&view=rev
Log:
Bugfix for PR17099:
Wrong cast operation.
MergeFunctions emits Bitcast instead of pointer-to-integer operation.
Patch fixes MergeFunctions::writeThunk function. It replaces
unconditional Bitcast creation with "Value* createCast(...)" method, that
checks operand types and selects proper instruction.
See unit-test as example.


Added:
    llvm/trunk/test/Transforms/MergeFunc/merge-ptr-and-int.ll
Modified:
    llvm/trunk/lib/Transforms/IPO/MergeFunctions.cpp

Modified: llvm/trunk/lib/Transforms/IPO/MergeFunctions.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/MergeFunctions.cpp?rev=190859&r1=190858&r2=190859&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/MergeFunctions.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/MergeFunctions.cpp Tue Sep 17 04:36:11 2013
@@ -713,6 +713,19 @@ void MergeFunctions::writeThunkOrAlias(F
   writeThunk(F, G);
 }
 
+// Helper for writeThunk,
+// Selects proper bitcast operation,
+// but a bit simplier then CastInst::getCastOpcode.
+static Value* createCast(IRBuilder<false> &Builder, Value *V, Type *DestTy) {
+  Type *SrcTy = V->getType();
+  if (SrcTy->isIntegerTy() && DestTy->isPointerTy())
+    return Builder.CreateIntToPtr(V, DestTy);
+  else if (SrcTy->isPointerTy() && DestTy->isIntegerTy())
+    return Builder.CreatePtrToInt(V, DestTy);
+  else
+    return Builder.CreateBitCast(V, DestTy);
+}
+
 // Replace G with a simple tail call to bitcast(F). Also replace direct uses
 // of G with bitcast(F). Deletes G.
 void MergeFunctions::writeThunk(Function *F, Function *G) {
@@ -738,7 +751,7 @@ void MergeFunctions::writeThunk(Function
   FunctionType *FFTy = F->getFunctionType();
   for (Function::arg_iterator AI = NewG->arg_begin(), AE = NewG->arg_end();
        AI != AE; ++AI) {
-    Args.push_back(Builder.CreateBitCast(AI, FFTy->getParamType(i)));
+    Args.push_back(createCast(Builder, (Value*)AI, FFTy->getParamType(i)));
     ++i;
   }
 
@@ -748,13 +761,7 @@ void MergeFunctions::writeThunk(Function
   if (NewG->getReturnType()->isVoidTy()) {
     Builder.CreateRetVoid();
   } else {
-    Type *RetTy = NewG->getReturnType();
-    if (CI->getType()->isIntegerTy() && RetTy->isPointerTy())
-      Builder.CreateRet(Builder.CreateIntToPtr(CI, RetTy));
-    else if (CI->getType()->isPointerTy() && RetTy->isIntegerTy())
-      Builder.CreateRet(Builder.CreatePtrToInt(CI, RetTy));
-    else
-      Builder.CreateRet(Builder.CreateBitCast(CI, RetTy));
+    Builder.CreateRet(createCast(Builder, CI, NewG->getReturnType()));
   }
 
   NewG->copyAttributesFrom(G);

Added: llvm/trunk/test/Transforms/MergeFunc/merge-ptr-and-int.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/MergeFunc/merge-ptr-and-int.ll?rev=190859&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/MergeFunc/merge-ptr-and-int.ll (added)
+++ llvm/trunk/test/Transforms/MergeFunc/merge-ptr-and-int.ll Tue Sep 17 04:36:11 2013
@@ -0,0 +1,18 @@
+; RUN: opt -S -mergefunc < %s | FileCheck %s
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+
+; CHECK-LABEL: f0
+define void @f0(i64 %p0) {
+entry:
+  ret void
+}
+
+; CHECK-LABEL: f1
+; CHECK: ptrtoint i64*
+; CHECK: tail call void @f0(i64
+
+define void @f1(i64* %p0) {
+entry:
+  ret void
+}
+