[llvm-commits] [llvm] r44318 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/select.ll

[Chris Lattner]

Author: lattner
Date: Sun Nov 25 15:27:53 2007
New Revision: 44318

URL: http://llvm.org/viewvc/llvm-project?rev=44318&view=rev
Log:
Implement PR1822

Modified:
    llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
    llvm/trunk/test/Transforms/InstCombine/select.ll

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=44318&r1=44317&r2=44318&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Sun Nov 25 15:27:53 2007
@@ -7326,6 +7326,13 @@
         return BinaryOperator::createOr(NotCond, TrueVal);
       }
     }
+    
+    // select a, b, a  -> a&b
+    // select a, a, b  -> a|b
+    if (CondVal == TrueVal)
+      return BinaryOperator::createOr(CondVal, FalseVal);
+    else if (CondVal == FalseVal)
+      return BinaryOperator::createAnd(CondVal, TrueVal);
   }
 
   // Selecting between two integer constants?

Modified: llvm/trunk/test/Transforms/InstCombine/select.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/select.ll?rev=44318&r1=44317&r2=44318&view=diff

==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/select.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/select.ll Sun Nov 25 15:27:53 2007
@@ -1,8 +1,7 @@
 ; This test makes sure that these instructions are properly eliminated.
+; PR1822
 
-; RUN: llvm-upgrade < %s | llvm-as | opt -instcombine | llvm-dis | \
-; RUN:    not grep select
-; END.
+; RUN: llvm-upgrade < %s | llvm-as | opt -instcombine | llvm-dis | not grep select
 
 implementation
 
@@ -180,3 +179,12 @@
         ret short %retval
 }
 
+bool %test23(bool %a, bool %b) {
+	%c = select bool %a, bool %b, bool %a
+	ret bool %c
+}
+
+bool %test24(bool %a, bool %b) {
+	%c = select bool %a, bool %a, bool %b
+	ret bool %c
+}