diff options
| -rw-r--r-- | lib/Transforms/Scalar/IndVarSimplify.cpp | 6 | ||||
| -rw-r--r-- | test/Transforms/IndVarSimplify/no-iv-rewrite.ll | 35 |
2 files changed, 35 insertions, 6 deletions
diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp index b75db7d..55094b9 100644 --- a/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -1419,6 +1419,11 @@ void IndVarSimplify::SimplifyCongruentIVs(Loop *L) { if (Inserted) continue; PHINode *OrigPhi = Pos->second; + + // If one phi derives from the other via GEPs, types may differ. + if (OrigPhi->getType() != Phi->getType()) + continue; + // Replacing the congruent phi is sufficient because acyclic redundancy // elimination, CSE/GVN, should handle the rest. However, once SCEV proves // that a phi is congruent, it's almost certain to be the head of an IV @@ -1430,6 +1435,7 @@ void IndVarSimplify::SimplifyCongruentIVs(Loop *L) { Instruction *IsomorphicInc = cast<Instruction>(Phi->getIncomingValueForBlock(LatchBlock)); if (OrigInc != IsomorphicInc && + OrigInc->getType() == IsomorphicInc->getType() && SE->getSCEV(OrigInc) == SE->getSCEV(IsomorphicInc) && HoistStep(OrigInc, IsomorphicInc, DT)) { DEBUG(dbgs() << "INDVARS: Eliminated congruent iv.inc: " diff --git a/test/Transforms/IndVarSimplify/no-iv-rewrite.ll b/test/Transforms/IndVarSimplify/no-iv-rewrite.ll index 9605670..bb951c6 100644 --- a/test/Transforms/IndVarSimplify/no-iv-rewrite.ll +++ b/test/Transforms/IndVarSimplify/no-iv-rewrite.ll @@ -125,9 +125,9 @@ return: ret void } -%struct = type { i32 } +%structI = type { i32 } -define void @bitcastiv(i32 %start, i32 %limit, i32 %step, %struct* %base) +define void @bitcastiv(i32 %start, i32 %limit, i32 %step, %structI* %base) nounwind { entry: @@ -142,12 +142,12 @@ entry: ; CHECK: exit: loop: %iv = phi i32 [%start, %entry], [%next, %loop] - %p = phi %struct* [%base, %entry], [%pinc, %loop] - %adr = getelementptr %struct* %p, i32 0, i32 0 + %p = phi %structI* [%base, %entry], [%pinc, %loop] + %adr = getelementptr %structI* %p, i32 0, i32 0 store i32 3, i32* %adr - %pp = bitcast %struct* %p to i32* + %pp = bitcast %structI* %p to i32* store i32 4, i32* %pp - %pinc = getelementptr %struct* %p, i32 1 + %pinc = getelementptr %structI* %p, i32 1 %next = add i32 %iv, 1 %cond = icmp ne i32 %next, %limit br i1 %cond, label %loop, label %exit @@ -320,3 +320,26 @@ return: %sum4 = add i32 %sum1, %l.next ret i32 %sum4 } + +; Test a GEP IV that is derived from another GEP IV by a nop gep that +; lowers the type without changing the expression. +%structIF = type { i32, float } + +define void @congruentgepiv(%structIF* %base) nounwind uwtable ssp { +entry: + %first = getelementptr inbounds %structIF* %base, i64 0, i32 0 + br label %loop + +loop: + %ptr.iv = phi %structIF* [ %ptr.inc, %latch ], [ %base, %entry ] + %next = phi i32* [ %next.inc, %latch ], [ %first, %entry ] + br i1 undef, label %latch, label %exit + +latch: ; preds = %for.inc50.i + %ptr.inc = getelementptr inbounds %structIF* %ptr.iv, i64 1 + %next.inc = getelementptr inbounds %structIF* %ptr.inc, i64 0, i32 0 + br label %loop + +exit: + ret void +} |