From: Sebastian Pop Date: Thu, 18 Oct 2012 19:53:48 +0000 (+0000) Subject: Clear unknown mem ops when merging stack slots (pr14090) X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=127777d686662445cd7a536125644531aaac75de;p=platform%2Fupstream%2Fllvm.git Clear unknown mem ops when merging stack slots (pr14090) When merging stack slots, if StackColoring::remapInstructions gets a value back from GetUnderlyingObject that it does not know about or is not itself a stack slot, clear the memory operand in case it aliases the merged slot. This prevents the introduction of incorrect aliasing information. Author: Matthew Curtis llvm-svn: 166216 --- diff --git a/llvm/lib/CodeGen/StackColoring.cpp b/llvm/lib/CodeGen/StackColoring.cpp index 3150f3d..1cbee84 100644 --- a/llvm/lib/CodeGen/StackColoring.cpp +++ b/llvm/lib/CodeGen/StackColoring.cpp @@ -261,7 +261,7 @@ unsigned StackColoring::collectMarkers(unsigned NumSlot) { MarkersFound++; - const Value *Allocation = MFI->getObjectAllocation(Slot); + const AllocaInst *Allocation = MFI->getObjectAllocation(Slot); if (Allocation) { DEBUG(dbgs()<<"Found a lifetime marker for slot #"<getName()<<"\n"); @@ -481,11 +481,11 @@ void StackColoring::remapInstructions(DenseMap &SlotRemap) { } // Keep a list of *allocas* which need to be remapped. - DenseMap Allocas; + DenseMap Allocas; for (DenseMap::iterator it = SlotRemap.begin(), e = SlotRemap.end(); it != e; ++it) { - const Value *From = MFI->getObjectAllocation(it->first); - const Value *To = MFI->getObjectAllocation(it->second); + const AllocaInst *From = MFI->getObjectAllocation(it->first); + const AllocaInst *To = MFI->getObjectAllocation(it->second); assert(To && From && "Invalid allocation object"); Allocas[From] = To; } @@ -515,10 +515,17 @@ void StackColoring::remapInstructions(DenseMap &SlotRemap) { V = GetUnderlyingObject(V); // If we did not find one, or if the one that we found is not in our // map, then move on. - if (!V || !Allocas.count(V)) + if (!V || !isa(V)) { + // Clear mem operand since we don't know for sure that it doesn't + // alias a merged alloca. + MMO->setValue(0); + continue; + } + const AllocaInst *AI= cast(V); + if (!Allocas.count(AI)) continue; - MMO->setValue(Allocas[V]); + MMO->setValue(Allocas[AI]); FixedMemOp++; } diff --git a/llvm/test/CodeGen/X86/pr14090.ll b/llvm/test/CodeGen/X86/pr14090.ll new file mode 100644 index 0000000..d76b912 --- /dev/null +++ b/llvm/test/CodeGen/X86/pr14090.ll @@ -0,0 +1,76 @@ +; RUN: llc < %s -march=x86-64 -print-before=stack-coloring -print-after=stack-coloring >%t 2>&1 && FileCheck <%t %s + +define void @foo(i64* %retval.i, i32 %call, i32* %.ph.i80, i32 %fourteen, i32* %out.lo, i32* %out.hi) nounwind align 2 { +entry: + %_Tmp.i39 = alloca i64, align 8 + %retval.i33 = alloca i64, align 8 + %_Tmp.i = alloca i64, align 8 + %retval.i.i = alloca i64, align 8 + %_First.i = alloca i64, align 8 + + %0 = load i64* %retval.i, align 8 + + %1 = load i64* %retval.i, align 8 + + %_Tmp.i39.0.cast73 = bitcast i64* %_Tmp.i39 to i8* + call void @llvm.lifetime.start(i64 8, i8* %_Tmp.i39.0.cast73) + store i64 %1, i64* %_Tmp.i39, align 8 + %cmp.i.i.i40 = icmp slt i32 %call, 0 + %2 = lshr i64 %1, 32 + %3 = trunc i64 %2 to i32 + %sub.i.i.i44 = sub i32 0, %call + %cmp2.i.i.i45 = icmp ult i32 %3, %sub.i.i.i44 + %or.cond.i.i.i46 = and i1 %cmp.i.i.i40, %cmp2.i.i.i45 + %add.i.i.i47 = add i32 %3, %call + %sub5.i.i.i48 = lshr i32 %add.i.i.i47, 5 + %trunc.i50 = trunc i64 %1 to i32 + %inttoptr.i51 = inttoptr i32 %trunc.i50 to i32* + %add61617.i.i.i52 = or i32 %sub5.i.i.i48, -134217728 + %add61617.i.sub5.i.i.i53 = select i1 %or.cond.i.i.i46, i32 %add61617.i.i.i52, i32 %sub5.i.i.i48 + %storemerge2.i.i54 = getelementptr inbounds i32* %inttoptr.i51, i32 %add61617.i.sub5.i.i.i53 + %_Tmp.i39.0.cast74 = bitcast i64* %_Tmp.i39 to i32** + store i32* %storemerge2.i.i54, i32** %_Tmp.i39.0.cast74, align 8 + %storemerge.i.i55 = and i32 %add.i.i.i47, 31 + %_Tmp.i39.4.raw_idx = getelementptr inbounds i8* %_Tmp.i39.0.cast73, i32 4 + %_Tmp.i39.4.cast = bitcast i8* %_Tmp.i39.4.raw_idx to i32* + store i32 %storemerge.i.i55, i32* %_Tmp.i39.4.cast, align 4 + %srcval.i56 = load i64* %_Tmp.i39, align 8 + call void @llvm.lifetime.end(i64 8, i8* %_Tmp.i39.0.cast73) + +; CHECK: Before Merge disjoint stack slots +; CHECK: [[PREFIX15:MOV64mr.*] + + %fifteen = bitcast i64* %retval.i.i to i32** + %sixteen = bitcast i64* %retval.i.i to i8* + call void @llvm.lifetime.start(i64 8, i8* %sixteen) + store i32* %.ph.i80, i32** %fifteen, align 8, !tbaa !0 + %sunkaddr = ptrtoint i64* %retval.i.i to i32 + %sunkaddr86 = add i32 %sunkaddr, 4 + %sunkaddr87 = inttoptr i32 %sunkaddr86 to i32* + store i32 %fourteen, i32* %sunkaddr87, align 4, !tbaa !3 + %seventeen = load i64* %retval.i.i, align 8 + call void @llvm.lifetime.end(i64 8, i8* %sixteen) + %eighteen = lshr i64 %seventeen, 32 + %nineteen = trunc i64 %eighteen to i32 + %shl.i.i.i = shl i32 1, %nineteen + + store i32 %shl.i.i.i, i32* %out.lo, align 8 + store i32 %nineteen, i32* %out.hi, align 8 + + ret void +} + +declare void @llvm.lifetime.start(i64, i8* nocapture) nounwind + +declare void @llvm.lifetime.end(i64, i8* nocapture) nounwind + +!0 = metadata !{metadata !"int", metadata !1} +!1 = metadata !{metadata !"omnipotent char", metadata !2} +!2 = metadata !{metadata !"Simple C/C++ TBAA"} +!3 = metadata !{metadata !"any pointer", metadata !1} +!4 = metadata !{metadata !"vtable pointer", metadata !2}