diff --git a/llvm/lib/Transforms/Utils/LoopSimplify.cpp b/llvm/lib/Transforms/Utils/LoopSimplify.cpp index f77a58300f4a..2e5b1136586f 100644 --- a/llvm/lib/Transforms/Utils/LoopSimplify.cpp +++ b/llvm/lib/Transforms/Utils/LoopSimplify.cpp @@ -91,7 +91,6 @@ namespace { AU.addPreserved(); AU.addPreservedID(BreakCriticalEdgesID); // No critical edges added. AU.addPreserved(); - AU.addPreservedID(LCSSAID); } /// verifyAnalysis() - Verify LoopSimplifyForm's guarantees. @@ -269,12 +268,11 @@ ReprocessLoop: PHINode *PN; for (BasicBlock::iterator I = L->getHeader()->begin(); (PN = dyn_cast(I++)); ) - if (Value *V = SimplifyInstruction(PN, 0, DT)) - if (LI->replacementPreservesLCSSAForm(PN, V)) { - if (AA) AA->deleteValue(PN); - PN->replaceAllUsesWith(V); - PN->eraseFromParent(); - } + if (Value *V = SimplifyInstruction(PN, 0, DT)) { + if (AA) AA->deleteValue(PN); + PN->replaceAllUsesWith(V); + PN->eraseFromParent(); + } // If this loop has multiple exits and the exits all go to the same // block, attempt to merge the exits. This helps several passes, such @@ -450,14 +448,13 @@ static PHINode *FindPHIToPartitionLoops(Loop *L, DominatorTree *DT, for (BasicBlock::iterator I = L->getHeader()->begin(); isa(I); ) { PHINode *PN = cast(I); ++I; - if (Value *V = SimplifyInstruction(PN, 0, DT)) - if (LI->replacementPreservesLCSSAForm(PN, V)) { - // This is a degenerate PHI already, don't modify it! - PN->replaceAllUsesWith(V); - if (AA) AA->deleteValue(PN); - PN->eraseFromParent(); - continue; - } + if (Value *V = SimplifyInstruction(PN, 0, DT)) { + // This is a degenerate PHI already, don't modify it! + PN->replaceAllUsesWith(V); + if (AA) AA->deleteValue(PN); + PN->eraseFromParent(); + continue; + } // Scan this PHI node looking for a use of the PHI node by itself. for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) diff --git a/llvm/test/Transforms/LoopSimplify/2010-12-26-PHIInfiniteLoop.ll b/llvm/test/Transforms/LoopSimplify/2010-12-26-PHIInfiniteLoop.ll new file mode 100644 index 000000000000..4973d43b4512 --- /dev/null +++ b/llvm/test/Transforms/LoopSimplify/2010-12-26-PHIInfiniteLoop.ll @@ -0,0 +1,43 @@ +; RUN: opt < %s -loopsimplify -S +; PR8702 +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" +target triple = "x86_64-unknown-freebsd9.0" + +declare void @foo(i32 %x) + +define fastcc void @inm_merge() nounwind { +entry: + br label %for.cond + +for.cond: ; preds = %while.cond36.i, %entry + br i1 undef, label %do.body, label %for.body + +for.body: ; preds = %for.cond + br i1 undef, label %while.cond36.i, label %if.end44 + +if.end44: ; preds = %for.body + %call49 = call fastcc i32 @inm_get_source() + br i1 undef, label %if.end54, label %for.cond64 + +if.end54: ; preds = %if.end44 + br label %while.cond36.i + +while.cond36.i: ; preds = %if.end54, %for.body + br label %for.cond + +for.cond64: ; preds = %if.end88, %for.cond64, %if.end44 + %error.161 = phi i32 [ %error.161, %for.cond64 ], [ %error.161, %if.end88 ], [ %call49, %if.end44 ] + call void @foo(i32 %error.161) + br i1 undef, label %for.cond64, label %if.end88 + +if.end88: ; preds = %for.cond64 + br i1 undef, label %for.cond64, label %if.end98 + +if.end98: ; preds = %if.end88 + unreachable + +do.body: ; preds = %for.cond + unreachable +} + +declare fastcc i32 @inm_get_source() nounwind