diff options
| -rw-r--r-- | llvm/lib/Analysis/LoopInfo.cpp | 9 | ||||
| -rw-r--r-- | llvm/lib/Transforms/Utils/LCSSA.cpp | 7 | ||||
| -rw-r--r-- | llvm/test/Transforms/LCSSA/mixed-catch.ll | 95 |
3 files changed, 110 insertions, 1 deletions
diff --git a/llvm/lib/Analysis/LoopInfo.cpp b/llvm/lib/Analysis/LoopInfo.cpp index dc97340a1f6..9ab9eead584 100644 --- a/llvm/lib/Analysis/LoopInfo.cpp +++ b/llvm/lib/Analysis/LoopInfo.cpp @@ -179,7 +179,13 @@ PHINode *Loop::getCanonicalInductionVariable() const { bool Loop::isLCSSAForm(DominatorTree &DT) const { for (block_iterator BI = block_begin(), E = block_end(); BI != E; ++BI) { BasicBlock *BB = *BI; - for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;++I) + for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;++I) { + // Tokens can't be used in PHI nodes and live-out tokens prevent loop + // optimizations, so for the purposes of considered LCSSA form, we + // can ignore them. + if (I->getType()->isTokenTy()) + continue; + for (Use &U : I->uses()) { Instruction *UI = cast<Instruction>(U.getUser()); BasicBlock *UserBB = UI->getParent(); @@ -195,6 +201,7 @@ bool Loop::isLCSSAForm(DominatorTree &DT) const { DT.isReachableFromEntry(UserBB)) return false; } + } } return true; diff --git a/llvm/lib/Transforms/Utils/LCSSA.cpp b/llvm/lib/Transforms/Utils/LCSSA.cpp index ef2f5042169..b4b2e148dfb 100644 --- a/llvm/lib/Transforms/Utils/LCSSA.cpp +++ b/llvm/lib/Transforms/Utils/LCSSA.cpp @@ -66,6 +66,13 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT, PredIteratorCache &PredCache, LoopInfo *LI) { SmallVector<Use *, 16> UsesToRewrite; + // Tokens cannot be used in PHI nodes, so we skip over them. + // We can run into tokens which are live out of a loop with catchswitch + // instructions in Windows EH if the catchswitch has one catchpad which + // is inside the loop and another which is not. + if (Inst.getType()->isTokenTy()) + return false; + BasicBlock *InstBB = Inst.getParent(); for (Use &U : Inst.uses()) { diff --git a/llvm/test/Transforms/LCSSA/mixed-catch.ll b/llvm/test/Transforms/LCSSA/mixed-catch.ll new file mode 100644 index 00000000000..95d5b17bf08 --- /dev/null +++ b/llvm/test/Transforms/LCSSA/mixed-catch.ll @@ -0,0 +1,95 @@ +; RUN: opt -lcssa -S < %s | FileCheck %s + +; This test is based on the following C++ code: +; +; void f() +; { +; for (int i=0; i<12; i++) { +; try { +; if (i==3) +; throw i; +; } catch (int) { +; continue; +; } catch (...) { } +; if (i==3) break; +; } +; } +; +; The loop info analysis identifies the catch pad for the second catch as being +; outside the loop (because it returns to %for.end) but the associated +; catchswitch block is identified as being inside the loop. Because of this +; analysis, the LCSSA pass wants to create a PHI node in the catchpad block +; for the catchswitch value, but this is a token, so it can't. + +define void @f() personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*) { +entry: + %tmp = alloca i32, align 4 + %i7 = alloca i32, align 4 + br label %for.cond + +for.cond: ; preds = %for.inc, %entry + %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ] + %cmp = icmp slt i32 %i.0, 12 + br i1 %cmp, label %for.body, label %for.end + +for.body: ; preds = %for.cond + %cond = icmp eq i32 %i.0, 3 + br i1 %cond, label %if.then, label %for.inc + +if.then: ; preds = %for.body + store i32 %i.0, i32* %tmp, align 4 + %tmp1 = bitcast i32* %tmp to i8* + invoke void @_CxxThrowException(i8* %tmp1, %eh.ThrowInfo* nonnull @_TI1H) #1 + to label %unreachable unwind label %catch.dispatch + +catch.dispatch: ; preds = %if.then + %tmp2 = catchswitch within none [label %catch, label %catch2] unwind to caller + +catch: ; preds = %catch.dispatch + %tmp3 = catchpad within %tmp2 [%rtti.TypeDescriptor2* @"\01??_R0H@8", i32 0, i32* %i7] + catchret from %tmp3 to label %for.inc + +catch2: ; preds = %catch.dispatch + %tmp4 = catchpad within %tmp2 [i8* null, i32 64, i8* null] + catchret from %tmp4 to label %for.end + +for.inc: ; preds = %catch, %for.body + %inc = add nsw i32 %i.0, 1 + br label %for.cond + +for.end: ; preds = %catch2, %for.cond + ret void + +unreachable: ; preds = %if.then + unreachable +} + +; CHECK-LABEL: define void @f() +; CHECK: catch2: +; CHECK-NOT: phi +; CHECK: %tmp4 = catchpad within %tmp2 +; CHECK: catchret from %tmp4 to label %for.end + +%rtti.TypeDescriptor2 = type { i8**, i8*, [3 x i8] } +%eh.CatchableType = type { i32, i32, i32, i32, i32, i32, i32 } +%eh.CatchableTypeArray.1 = type { i32, [1 x i32] } +%eh.ThrowInfo = type { i32, i32, i32, i32 } + +$"\01??_R0H@8" = comdat any + +$"_CT??_R0H@84" = comdat any + +$_CTA1H = comdat any + +$_TI1H = comdat any + +@"\01??_7type_info@@6B@" = external constant i8* +@"\01??_R0H@8" = linkonce_odr global %rtti.TypeDescriptor2 { i8** @"\01??_7type_info@@6B@", i8* null, [3 x i8] c".H\00" }, comdat +@__ImageBase = external constant i8 +@"_CT??_R0H@84" = linkonce_odr unnamed_addr constant %eh.CatchableType { i32 1, i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.TypeDescriptor2* @"\01??_R0H@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 0, i32 -1, i32 0, i32 4, i32 0 }, section ".xdata", comdat +@_CTA1H = linkonce_odr unnamed_addr constant %eh.CatchableTypeArray.1 { i32 1, [1 x i32] [i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%eh.CatchableType* @"_CT??_R0H@84" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32)] }, section ".xdata", comdat +@_TI1H = linkonce_odr unnamed_addr constant %eh.ThrowInfo { i32 0, i32 0, i32 0, i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%eh.CatchableTypeArray.1* @_CTA1H to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, section ".xdata", comdat + +declare void @_CxxThrowException(i8*, %eh.ThrowInfo*) + +declare i32 @__CxxFrameHandler3(...) |
