[llvm-commits] CVS: llvm/lib/Transforms/Scalar/InstructionCombining.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.340 -> 1.341
---
Log message:

Fix a miscompilation of crafty by clobbering the "A" variable.


---
Diffs of the changes:  (+10 -9)

 InstructionCombining.cpp |   19 ++++++++++---------
 1 files changed, 10 insertions(+), 9 deletions(-)


Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.340 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.341
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.340	Fri May  6 01:48:21 2005
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Sat May  7 18:49:08 2005
@@ -1856,8 +1856,16 @@
         return NV;
   }
 
-  // (A & C1)|(A & C2) == A & (C1|C2)
   Value *A, *B; ConstantInt *C1, *C2;
+
+  if (match(Op0, m_And(m_Value(A), m_Value(B))))
+    if (A == Op1 || B == Op1)    // (A & ?) | A  --> A
+      return ReplaceInstUsesWith(I, Op1);
+  if (match(Op1, m_And(m_Value(A), m_Value(B))))
+    if (A == Op0 || B == Op0)    // A | (A & ?)  --> A
+      return ReplaceInstUsesWith(I, Op0);
+
+  // (A & C1)|(A & C2) == A & (C1|C2)
   if (match(Op0, m_And(m_Value(A), m_ConstantInt(C1))) &&
       match(Op1, m_And(m_Value(B), m_ConstantInt(C2))) && A == B)
     return BinaryOperator::createAnd(A, ConstantExpr::getOr(C1, C2));
@@ -1869,14 +1877,7 @@
   } else {
     A = 0;
   }
-
-  if (match(Op0, m_And(m_Value(A), m_Value(B))))
-    if (A == Op1 || B == Op1)    // (A & ?) | A  --> A
-      return ReplaceInstUsesWith(I, Op1);
-  if (match(Op1, m_And(m_Value(A), m_Value(B))))
-    if (A == Op0 || B == Op0)    // A | (A & ?)  --> A
-      return ReplaceInstUsesWith(I, Op0);
-
+  // Note, A is still live here!
   if (match(Op1, m_Not(m_Value(B)))) {   // Op0 | ~B
     if (Op0 == B)
       return ReplaceInstUsesWith(I,