[llvm-commits] [llvm] r108113 - in /llvm/trunk: lib/Analysis/ConstantFolding.cpp test/Transforms/InstCombine/load3.ll

[Chris Lattner]

Author: lattner
Date: Sun Jul 11 19:22:51 2010
New Revision: 108113

URL: http://llvm.org/viewvc/llvm-project?rev=108113&view=rev
Log:
fix PR7429, a crash turning a load from a string into a float.

Modified:
    llvm/trunk/lib/Analysis/ConstantFolding.cpp
    llvm/trunk/test/Transforms/InstCombine/load3.ll

Modified: llvm/trunk/lib/Analysis/ConstantFolding.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ConstantFolding.cpp?rev=108113&r1=108112&r2=108113&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ConstantFolding.cpp (original)
+++ llvm/trunk/lib/Analysis/ConstantFolding.cpp Sun Jul 11 19:22:51 2010
@@ -436,8 +436,10 @@
     unsigned StrLen = Str.length();
     const Type *Ty = cast<PointerType>(CE->getType())->getElementType();
     unsigned NumBits = Ty->getPrimitiveSizeInBits();
-    // Replace LI with immediate integer store.
-    if ((NumBits >> 3) == StrLen + 1) {
+    // Replace load with immediate integer if the result is an integer or fp
+    // value.
+    if ((NumBits >> 3) == StrLen + 1 && (NumBits & 7) == 0 &&
+        isa<IntegerType>(Ty) || Ty->isFloatingPointTy()) {
       APInt StrVal(NumBits, 0);
       APInt SingleChar(NumBits, 0);
       if (TD->isLittleEndian()) {
@@ -454,7 +456,11 @@
         SingleChar = 0;
         StrVal = (StrVal << 8) | SingleChar;
       }
-      return ConstantInt::get(CE->getContext(), StrVal);
+      
+      Constant *Res = ConstantInt::get(CE->getContext(), StrVal);
+      if (Ty->isFloatingPointTy())
+        Res = ConstantExpr::getBitCast(Res, Ty);
+      return Res;
     }
   }
   

Modified: llvm/trunk/test/Transforms/InstCombine/load3.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/load3.ll?rev=108113&r1=108112&r2=108113&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/load3.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/load3.ll Sun Jul 11 19:22:51 2010
@@ -1,4 +1,6 @@
 ; RUN: opt < %s -instcombine -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"
+target triple = "x86_64-apple-darwin10.0.0"
 
 ; Instcombine should be able to do trivial CSE of loads.
 
@@ -12,3 +14,14 @@
 ; CHECK: @test1
 ; CHECK: ret i32 0
 }
+
+
+; PR7429
+ at .str = private constant [4 x i8] c"XYZ\00"
+define float @test2() {
+  %tmp = load float* bitcast ([4 x i8]* @.str to float*), align 1
+  ret float %tmp
+  
+; CHECK: @test2
+; CHECK: ret float 0x3806965600000000
+}
\ No newline at end of file