diff options
| -rw-r--r-- | llvm/lib/CodeGen/CodePlacementOpt.cpp | 15 | ||||
| -rw-r--r-- | llvm/test/CodeGen/X86/code_placement_eh.ll | 45 |
2 files changed, 53 insertions, 7 deletions
diff --git a/llvm/lib/CodeGen/CodePlacementOpt.cpp b/llvm/lib/CodeGen/CodePlacementOpt.cpp index a13a310dec9..3ff2a046d23 100644 --- a/llvm/lib/CodeGen/CodePlacementOpt.cpp +++ b/llvm/lib/CodeGen/CodePlacementOpt.cpp @@ -102,13 +102,6 @@ bool CodePlacementOpt::HasAnalyzableTerminator(MachineBasicBlock *MBB) { // Conservatively ignore EH landing pads. if (MBB->isLandingPad()) return false; - // Ignore blocks which look like they might have EH-related control flow. - // At the time of this writing, there are blocks which AnalyzeBranch - // thinks end in single uncoditional branches, yet which have two CFG - // successors. Code in this file is not prepared to reason about such things. - if (!MBB->empty() && MBB->back().isEHLabel()) - return false; - // Aggressively handle return blocks and similar constructs. if (MBB->succ_empty()) return true; @@ -118,6 +111,14 @@ bool CodePlacementOpt::HasAnalyzableTerminator(MachineBasicBlock *MBB) { // Make sure the terminator is understood. if (TII->AnalyzeBranch(*MBB, TBB, FBB, Cond)) return false; + // Ignore blocks which look like they might have EH-related control flow. + // AnalyzeBranch thinks it knows how to analyze such things, but it doesn't + // recognize the possibility of a control transfer through an unwind. + // Such blocks contain EH_LABEL instructions, however they may be in the + // middle of the block. Instead of searching for them, just check to see + // if the CFG disagrees with AnalyzeBranch. + if (1u + !Cond.empty() != MBB->succ_size()) + return false; // Make sure we have the option of reversing the condition. if (!Cond.empty() && TII->ReverseBranchCondition(Cond)) return false; diff --git a/llvm/test/CodeGen/X86/code_placement_eh.ll b/llvm/test/CodeGen/X86/code_placement_eh.ll new file mode 100644 index 00000000000..172d5910d03 --- /dev/null +++ b/llvm/test/CodeGen/X86/code_placement_eh.ll @@ -0,0 +1,45 @@ +; RUN: llc < %s + +; CodePlacementOpt shouldn't try to modify this loop because +; it involves EH edges. + +target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32" +target triple = "i386-apple-darwin10.0" + +define void @foo() { +invcont5: + br label %bb15 + +.noexc3: ; preds = %bb15 + br i1 undef, label %bb18.i5.i, label %bb15 + +.noexc6.i.i: ; preds = %bb18.i5.i + %tmp2021 = invoke float @cosf(float 0.000000e+00) readonly + to label %bb18.i5.i unwind label %lpad.i.i ; <float> [#uses=0] + +bb18.i5.i: ; preds = %.noexc6.i.i, %bb51.i + %tmp2019 = invoke float @sinf(float 0.000000e+00) readonly + to label %.noexc6.i.i unwind label %lpad.i.i ; <float> [#uses=0] + +lpad.i.i: ; preds = %bb18.i5.i, %.noexc6.i.i + %eh_ptr.i.i = call i8* @llvm.eh.exception() ; <i8*> [#uses=1] + unreachable + +lpad59.i: ; preds = %bb15 + %eh_ptr60.i = call i8* @llvm.eh.exception() ; <i8*> [#uses=1] + unreachable + +bb15: ; preds = %.noexc3, %invcont5 + invoke fastcc void @_ZN28btHashedOverlappingPairCacheC2Ev() + to label %.noexc3 unwind label %lpad59.i +} + +declare i8* @llvm.eh.exception() nounwind readonly + +declare i32 @llvm.eh.selector(i8*, i8*, ...) nounwind + +declare float @sinf(float) readonly + +declare float @cosf(float) readonly + +declare fastcc void @_ZN28btHashedOverlappingPairCacheC2Ev() align 2 |
