diff options
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/Analysis/DivergenceAnalysis.cpp | 5 | ||||
| -rw-r--r-- | llvm/test/Analysis/DivergenceAnalysis/AMDGPU/unreachable-loop-block.ll | 17 |
2 files changed, 22 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/DivergenceAnalysis.cpp b/llvm/lib/Analysis/DivergenceAnalysis.cpp index b30539f3b31..d38725ff0ac 100644 --- a/llvm/lib/Analysis/DivergenceAnalysis.cpp +++ b/llvm/lib/Analysis/DivergenceAnalysis.cpp @@ -138,6 +138,11 @@ void DivergencePropagator::exploreSyncDependency(TerminatorInst *TI) { // a2 = 2; // a = phi(a1, a2); // sync dependent on (tid < 5) BasicBlock *ThisBB = TI->getParent(); + + // Unreachable blocks may not be in the dominator tree. + if (!DT.isReachableFromEntry(ThisBB)) + return; + BasicBlock *IPostDom = PDT.getNode(ThisBB)->getIDom()->getBlock(); if (IPostDom == nullptr) return; diff --git a/llvm/test/Analysis/DivergenceAnalysis/AMDGPU/unreachable-loop-block.ll b/llvm/test/Analysis/DivergenceAnalysis/AMDGPU/unreachable-loop-block.ll new file mode 100644 index 00000000000..ca93dda2c57 --- /dev/null +++ b/llvm/test/Analysis/DivergenceAnalysis/AMDGPU/unreachable-loop-block.ll @@ -0,0 +1,17 @@ +; RUN: opt %s -mtriple amdgcn-- -analyze -divergence | FileCheck %s + +; CHECK: DIVERGENT: %tmp = cmpxchg volatile +define void @unreachable_loop(i32 %tidx) #0 { +entry: + unreachable + +unreachable_loop: ; preds = %do.body.i, %if.then11 + %tmp = cmpxchg volatile i32 addrspace(1)* null, i32 0, i32 0 seq_cst seq_cst + %cmp.i = extractvalue { i32, i1 } %tmp, 1 + br i1 %cmp.i, label %unreachable_loop, label %end + +end: ; preds = %do.body.i51, %atomicAdd_g_f.exit + unreachable +} + +attributes #0 = { norecurse nounwind } |
