[llvm-commits] [llvm] r124713 - /llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
Dan Gohman
gohman at apple.com
Tue Feb 1 18:05:46 PST 2011
Author: djg
Date: Tue Feb 1 20:05:46 2011
New Revision: 124713
URL: http://llvm.org/viewvc/llvm-project?rev=124713&view=rev
Log:
Conservatively, clear optional flags, such as nsw, when performing
reassociation. No testcase, because I wasn't able to create a testcase
which actually demonstrates a problem.
Modified:
llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
Modified: llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp?rev=124713&r1=124712&r2=124713&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp Tue Feb 1 20:05:46 2011
@@ -157,6 +157,9 @@
// It simplifies to V. Form "A op V".
I.setOperand(0, A);
I.setOperand(1, V);
+ // Conservatively clear the optional flags, since they may not be
+ // preserved by the reassociation.
+ I.clearSubclassOptionalData();
Changed = true;
++NumReassoc;
continue;
@@ -174,6 +177,9 @@
// It simplifies to V. Form "V op C".
I.setOperand(0, V);
I.setOperand(1, C);
+ // Conservatively clear the optional flags, since they may not be
+ // preserved by the reassociation.
+ I.clearSubclassOptionalData();
Changed = true;
++NumReassoc;
continue;
@@ -193,6 +199,9 @@
// It simplifies to V. Form "V op B".
I.setOperand(0, V);
I.setOperand(1, B);
+ // Conservatively clear the optional flags, since they may not be
+ // preserved by the reassociation.
+ I.clearSubclassOptionalData();
Changed = true;
++NumReassoc;
continue;
@@ -210,6 +219,9 @@
// It simplifies to V. Form "B op V".
I.setOperand(0, B);
I.setOperand(1, V);
+ // Conservatively clear the optional flags, since they may not be
+ // preserved by the reassociation.
+ I.clearSubclassOptionalData();
Changed = true;
++NumReassoc;
continue;
@@ -234,6 +246,9 @@
Worklist.Add(New);
I.setOperand(0, New);
I.setOperand(1, Folded);
+ // Conservatively clear the optional flags, since they may not be
+ // preserved by the reassociation.
+ I.clearSubclassOptionalData();
Changed = true;
continue;
}
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