LoopProcessWorklist.push_back(NewLoop);
redoLoop = true;
+ // Keep a WeakVH holding onto LIC. If the first call to RewriteLoopBody
+ // deletes the instruction (for example by simplifying a PHI that feeds into
+ // the condition that we're unswitching on), we don't rewrite the second
+ // iteration.
+ WeakVH LICHandle(LIC);
+
// Now we rewrite the original code to know that the condition is true and the
// new code to know that the condition is false.
RewriteLoopBodyWithConditionConstant(L, LIC, Val, false);
-
- // It's possible that simplifying one loop could cause the other to be
- // deleted. If so, don't simplify it.
- if (!LoopProcessWorklist.empty() && LoopProcessWorklist.back() == NewLoop)
- RewriteLoopBodyWithConditionConstant(NewLoop, LIC, Val, true);
+ // It's possible that simplifying one loop could cause the other to be
+ // changed to another value or a constant. If its a constant, don't simplify
+ // it.
+ if (!LoopProcessWorklist.empty() && LoopProcessWorklist.back() == NewLoop &&
+ LICHandle && !isa<Constant>(LICHandle))
+ RewriteLoopBodyWithConditionConstant(NewLoop, LICHandle, Val, true);
}
/// RemoveFromWorklist - Remove all instances of I from the worklist vector
continue;
}
+ // FIXME: Change this to use instruction simplify interfaces!
+
// Special case hacks that appear commonly in unswitched code.
switch (I->getOpcode()) {
case Instruction::Select:
for.end: ; preds = %for.body, %entry
ret void
}
+
+; PR6879
+define i32* @test3(i32** %p_45, i16 zeroext %p_46, i64 %p_47, i64 %p_48, i16 signext %p_49) nounwind {
+entry:
+ br label %for.cond
+
+for.cond: ; preds = %for.cond4, %entry
+ br i1 false, label %for.cond4, label %for.end88
+
+for.cond4: ; preds = %for.cond
+ %conv46 = trunc i32 0 to i8 ; <i8> [#uses=2]
+ %cmp60 = icmp sgt i8 %conv46, 124 ; <i1> [#uses=1]
+ %or.cond = and i1 undef, %cmp60 ; <i1> [#uses=1]
+ %cond = select i1 %or.cond, i8 %conv46, i8 undef ; <i8> [#uses=0]
+ br label %for.cond
+
+for.end88: ; preds = %for.cond
+ ret i32* undef
+}