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

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.385 -> 1.386
---
Log message:

relax this a bit, as we only support the default rounding mode


---
Diffs of the changes:  (+4 -2)

 InstructionCombining.cpp |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)


Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.385 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.386
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.385	Sun Oct  9 17:08:50 2005
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Mon Oct 17 12:49:32 2005
@@ -694,8 +694,10 @@
       return ReplaceInstUsesWith(I, RHS);
 
     // X + 0 --> X
-    if (!I.getType()->isFloatingPoint() && // -0 + +0 = +0, so it's not a noop
-        RHSC->isNullValue())
+    // NOTE: -0 + +0 = +0 in non-default rounding modes.  When we support them
+    // we must disable this.  Note that 0.0-0.0 = -0.0, so this doesn't hold
+    // for SUB.
+    if (RHSC->isNullValue())
       return ReplaceInstUsesWith(I, LHS);
 
     // X + (signbit) --> X ^ signbit