Handle the case where there is no "not". It is possible it got

folded into the select.

llvm-svn: 59389

2 files changed, 16 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
index ac9fc01c20c..c2df3a5b243 100644
--- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -4222,9 +4222,13 @@ static Instruction *MatchSelectFromAndOr(Value *A, Value *B,
   // Handle "cond ? -1 : 0".
   if (C1->isAllOnesValue() && C2->isZero()) {
     // ((cond?-1:0)&C) | (B&(cond?0:-1)) -> cond ? C : B.
+    if (match(D, SELECT_MATCH(Cond2, 0, -1)) && Cond2 == Cond)
+      return SelectInst::Create(Cond, C, B);
     if (match(D, m_Not(SELECT_MATCH(Cond2, -1, 0))) && Cond2 == Cond)
       return SelectInst::Create(Cond, C, B);
     // ((cond?-1:0)&C) | ((cond?0:-1)&D) -> cond ? C : D.
+    if (match(B, SELECT_MATCH(Cond2, 0, -1)) && Cond2 == Cond)
+      return SelectInst::Create(Cond, C, D);
     if (match(B, m_Not(SELECT_MATCH(Cond2, -1, 0))) && Cond2 == Cond)
       return SelectInst::Create(Cond, C, D);
   }
diff --git a/llvm/test/Transforms/InstCombine/logical-select.ll b/llvm/test/Transforms/InstCombine/logical-select.ll
index ffdaa914545..3bb2d348b38 100644
--- a/llvm/test/Transforms/InstCombine/logical-select.ll
+++ b/llvm/test/Transforms/InstCombine/logical-select.ll
@@ -1,5 +1,5 @@
 ; RUN: llvm-as < %s | opt -instcombine | llvm-dis > %t
-; RUN: grep select %t | count 4
+; RUN: grep select %t | count 5
 ; RUN: not grep and %t
 ; RUN: not grep or %t
 
@@ -31,6 +31,17 @@ entry:
   %3 = or i32 %1, %2
   ret i32 %3
 }
+define i32 @poo(i32 %a, i32 %b, i32 %c, i32 %d) nounwind {
+entry:
+  %0 = icmp slt i32 %a, %b
+  %iftmp.0.0 = select i1 %0, i32 -1, i32 0
+  %1 = and i32 %iftmp.0.0, %c
+  %iftmp = select i1 %0, i32 0, i32 -1
+  %2 = and i32 %iftmp, %d
+  %3 = or i32 %1, %2
+  ret i32 %3
+}
+
 define i32 @par(i32 %a, i32 %b, i32 %c, i32 %d) nounwind {
 entry:
   %0 = icmp slt i32 %a, %b