diff options
3 files changed, 5 insertions, 37 deletions
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp index 4b89b0435e0..59837042550 100644 --- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp +++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp @@ -119,14 +119,7 @@ bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT, LoopInfo *LI, MemoryDependenceResults *MemDep) { // Don't merge away blocks who have their address taken. - if (BB->hasAddressTaken()) { - // If the block has its address taken, it may be a tree of dead constants - // hanging off of it. These shouldn't keep the block alive. - BlockAddress *BA = BlockAddress::get(BB); - BA->removeDeadConstantUsers(); - if (!BA->use_empty()) - return false; - } + if (BB->hasAddressTaken()) return false; // Can't merge if there are multiple predecessors, or no predecessors. BasicBlock *PredBB = BB->getUniquePredecessor(); diff --git a/llvm/test/Transforms/SimplifyCFG/dce-cond-after-folding-terminator.ll b/llvm/test/Transforms/SimplifyCFG/dce-cond-after-folding-terminator.ll index a15cdd6a28f..036a615e7ff 100644 --- a/llvm/test/Transforms/SimplifyCFG/dce-cond-after-folding-terminator.ll +++ b/llvm/test/Transforms/SimplifyCFG/dce-cond-after-folding-terminator.ll @@ -37,7 +37,10 @@ define void @test_indirectbr(i32 %x) { entry: ; CHECK-LABEL: @test_indirectbr( ; CHECK-NEXT: entry: -; CHECK-NEXT: ret void +; Ideally this should now check: +; CHK-NEXT: ret void +; But that doesn't happen yet. Instead: +; CHECK-NEXT: br label %L1 %label = bitcast i8* blockaddress(@test_indirectbr, %L1) to i8* indirectbr i8* %label, [label %L1, label %L2] diff --git a/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp b/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp index 590e7f6ada6..2d0a9302011 100644 --- a/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp +++ b/llvm/unittests/Transforms/Utils/BasicBlockUtils.cpp @@ -50,31 +50,3 @@ TEST(BasicBlockUtils, SplitBlockPredecessors) { SplitBlockPredecessors(&F->getEntryBlock(), {}, "split.entry", &DT); EXPECT_TRUE(DT.verify()); } - -TEST(BasicBlockUtils, MergeBlockIntoPredecessor) { - LLVMContext C; - std::unique_ptr<Module> M = parseIR(C, - R"( - - define i32 @f(i8* %str) { - entry: - %dead = extractvalue [1 x i8*] [ i8* blockaddress(@f, %L0) ], 0 - br label %L0 - L0: - ret i32 0 - } - )"); - - // First remove the dead instruction to empty the usage of the constant - // containing blockaddress(@f, %L0) - Function *F = M->getFunction("f"); - auto BBI = F->begin(); - Instruction *DI = &*((*BBI).begin()); - EXPECT_TRUE(DI->use_empty()); - DI->eraseFromParent(); - - // Get L0 and make sure that it can be merged into entry block. - ++BBI; - BasicBlock *BB = &(*BBI); - EXPECT_TRUE(MergeBlockIntoPredecessor(BB)); -} |
