ifcvt should ignore cfg where true and false successors are the same.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73423 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/IfConversion.cpp b/lib/CodeGen/IfConversion.cpp
index 1d0887f..4d5c3c2 100644
--- a/lib/CodeGen/IfConversion.cpp
+++ b/lib/CodeGen/IfConversion.cpp
@@ -547,7 +547,11 @@
// fallthrough.
if (!BBI.FalseBB)
BBI.FalseBB = findFalseBlock(BBI.BB, BBI.TrueBB);
- assert(BBI.FalseBB && "Expected to find the fallthrough block!");
+ if (!BBI.FalseBB) {
+ // Malformed bcc? True and false blocks are the same?
+ BBI.IsUnpredicable = true;
+ return;
+ }
}
// Then scan all the instructions.
@@ -663,6 +667,13 @@
return BBI;
}
+ // Do not ifcvt if true and false fallthrough blocks are the same.
+ if (!BBI.FalseBB) {
+ BBI.IsBeingAnalyzed = false;
+ BBI.IsAnalyzed = true;
+ return BBI;
+ }
+
BBInfo &TrueBBI = AnalyzeBlock(BBI.TrueBB, Tokens);
BBInfo &FalseBBI = AnalyzeBlock(BBI.FalseBB, Tokens);