Author: Arthur Eubanks Date: 2025-09-12T13:48:55-07:00 New Revision: a00dbed63394aa5e31b356a6430656d7e29a81a0
URL: https://github.com/llvm/llvm-project/commit/a00dbed63394aa5e31b356a6430656d7e29a81a0 DIFF: https://github.com/llvm/llvm-project/commit/a00dbed63394aa5e31b356a6430656d7e29a81a0.diff LOG: Revert "[BasicBlockUtils] Handle funclets when detaching EH pad blocks (#157363)" This reverts commit 43561ad204329667954d5ce1e632e09335f0ab12. Added: Modified: llvm/lib/Transforms/Utils/BasicBlockUtils.cpp Removed: llvm/test/Transforms/SimplifyCFG/unreachable-multi-basic-block-funclet.ll ################################################################################ diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp index d2391e166f942..cad0b4c12b54e 100644 --- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp +++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp @@ -58,19 +58,6 @@ static cl::opt<unsigned> MaxDeoptOrUnreachableSuccessorCheckDepth( "is followed by a block that either has a terminating " "deoptimizing call or is terminated with an unreachable")); -static void replaceFuncletPadsRetWithUnreachable(Instruction &I) { - assert(isa<FuncletPadInst>(I) && "Instruction must be a funclet pad!"); - for (User *User : make_early_inc_range(I.users())) { - Instruction *ReturnInstr = dyn_cast<Instruction>(User); - if (isa<CatchReturnInst>(ReturnInstr) || - isa<CleanupReturnInst>(ReturnInstr)) { - BasicBlock *ReturnInstrBB = ReturnInstr->getParent(); - ReturnInstr->eraseFromParent(); - new UnreachableInst(ReturnInstrBB->getContext(), ReturnInstrBB); - } - } -} - void llvm::detachDeadBlocks( ArrayRef<BasicBlock *> BBs, SmallVectorImpl<DominatorTree::UpdateType> *Updates, @@ -88,36 +75,7 @@ void llvm::detachDeadBlocks( // Zap all the instructions in the block. while (!BB->empty()) { Instruction &I = BB->back(); - // Exception handling funclets need to be explicitly addressed. - // These funclets must begin with cleanuppad or catchpad and end with - // cleanupred or catchret. The return instructions can be in diff erent - // basic blocks than the pad instruction. If we would only delete the - // first block, the we would have possible cleanupret and catchret - // instructions with poison arguments, which wouldn't be valid. - if (isa<FuncletPadInst>(I)) - replaceFuncletPadsRetWithUnreachable(I); - - // Catchswitch instructions have handlers, that must be catchpads and - // an unwind label, that is either a catchpad or catchswitch. - if (CatchSwitchInst *CSI = dyn_cast<CatchSwitchInst>(&I)) { - // Iterating over the handlers and the unwind basic block and processing - // catchpads. If the unwind label is a catchswitch, we just replace the - // label with poison later on. - for (unsigned I = 0; I < CSI->getNumSuccessors(); I++) { - BasicBlock *SucBlock = CSI->getSuccessor(I); - Instruction &SucFstInst = *(SucBlock->getFirstNonPHIIt()); - if (isa<FuncletPadInst>(SucFstInst)) { - replaceFuncletPadsRetWithUnreachable(SucFstInst); - // There may be catchswitch instructions using the catchpad. - // Just replace those with poison. - if (!SucFstInst.use_empty()) - SucFstInst.replaceAllUsesWith( - PoisonValue::get(SucFstInst.getType())); - SucFstInst.eraseFromParent(); - } - } - } - + // If this instruction is used, replace uses with an arbitrary value. // Because control flow can't get here, we don't care what we replace the // value with. Note that since this block is unreachable, and all values // contained within it must dominate their uses, that all uses will diff --git a/llvm/test/Transforms/SimplifyCFG/unreachable-multi-basic-block-funclet.ll b/llvm/test/Transforms/SimplifyCFG/unreachable-multi-basic-block-funclet.ll deleted file mode 100644 index d2fccae6770db..0000000000000 --- a/llvm/test/Transforms/SimplifyCFG/unreachable-multi-basic-block-funclet.ll +++ /dev/null @@ -1,169 +0,0 @@ -; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5 -; RUN: opt -passes=simplifycfg -S < %s | FileCheck %s - -; cleanuppad/cleanupret - -define void @unreachable_cleanuppad_linear(i64 %shapes.1) personality ptr null { -; CHECK-LABEL: define void @unreachable_cleanuppad_linear( -; CHECK-SAME: i64 [[SHAPES_1:%.*]]) personality ptr null { -; CHECK-NEXT: [[START:.*:]] -; CHECK-NEXT: [[_7:%.*]] = icmp ult i64 0, [[SHAPES_1]] -; CHECK-NEXT: ret void -; -start: - %_7 = icmp ult i64 0, %shapes.1 - ret void - -funclet: - %cleanuppad = cleanuppad within none [] - br label %funclet_end - -funclet_end: - cleanupret from %cleanuppad unwind to caller -} - -define void @unreachable_cleanuppad_multiple_predecessors(i64 %shapes.1) personality ptr null { -; CHECK-LABEL: define void @unreachable_cleanuppad_multiple_predecessors( -; CHECK-SAME: i64 [[SHAPES_1:%.*]]) personality ptr null { -; CHECK-NEXT: [[START:.*:]] -; CHECK-NEXT: [[_7:%.*]] = icmp ult i64 0, [[SHAPES_1]] -; CHECK-NEXT: ret void -; -start: - %_7 = icmp ult i64 0, %shapes.1 - ret void - -funclet: - %cleanuppad = cleanuppad within none [] - switch i64 %shapes.1, label %otherwise [ i64 0, label %one - i64 1, label %two - i64 42, label %three ] -one: - br label %funclet_end - -two: - br label %funclet_end - -three: - br label %funclet_end - -otherwise: - br label %funclet_end - -funclet_end: - cleanupret from %cleanuppad unwind to caller -} - -; catchpad/catchret - -define void @unreachable_catchpad_linear(i64 %shapes.1) personality ptr null { -; CHECK-LABEL: define void @unreachable_catchpad_linear( -; CHECK-SAME: i64 [[SHAPES_1:%.*]]) personality ptr null { -; CHECK-NEXT: [[START:.*:]] -; CHECK-NEXT: [[_7:%.*]] = icmp ult i64 0, [[SHAPES_1]] -; CHECK-NEXT: ret void -; -start: - %_7 = icmp ult i64 0, %shapes.1 - ret void - -dispatch: - %cs = catchswitch within none [label %funclet] unwind to caller - -funclet: - %cleanuppad = catchpad within %cs [] - br label %funclet_end - - -funclet_end: - catchret from %cleanuppad to label %unreachable - -unreachable: - unreachable -} - -define void @unreachable_catchpad_multiple_predecessors(i64 %shapes.1) personality ptr null { -; CHECK-LABEL: define void @unreachable_catchpad_multiple_predecessors( -; CHECK-SAME: i64 [[SHAPES_1:%.*]]) personality ptr null { -; CHECK-NEXT: [[START:.*:]] -; CHECK-NEXT: [[_7:%.*]] = icmp ult i64 0, [[SHAPES_1]] -; CHECK-NEXT: ret void -; -start: - %_7 = icmp ult i64 0, %shapes.1 - ret void - -dispatch: - %cs = catchswitch within none [label %funclet] unwind to caller - -funclet: - %cleanuppad = catchpad within %cs [] - switch i64 %shapes.1, label %otherwise [ i64 0, label %one - i64 1, label %two - i64 42, label %three ] -one: - br label %funclet_end - -two: - br label %funclet_end - -three: - br label %funclet_end - -otherwise: - br label %funclet_end - -funclet_end: - catchret from %cleanuppad to label %unreachable - -unreachable: - unreachable -} - -; Issue reproducer - -define void @gh148052(i64 %shapes.1) personality ptr null { -; CHECK-LABEL: define void @gh148052( -; CHECK-SAME: i64 [[SHAPES_1:%.*]]) personality ptr null { -; CHECK-NEXT: [[START:.*:]] -; CHECK-NEXT: [[_7:%.*]] = icmp ult i64 0, [[SHAPES_1]] -; CHECK-NEXT: call void @llvm.assume(i1 [[_7]]) -; CHECK-NEXT: ret void -; -start: - %_7 = icmp ult i64 0, %shapes.1 - br i1 %_7, label %bb1, label %panic - -bb1: - %_11 = icmp ult i64 0, %shapes.1 - br i1 %_11, label %bb3, label %panic1 - -panic: - unreachable - -bb3: - ret void - -panic1: - invoke void @func(i64 0, i64 0, ptr null) - to label %unreachable unwind label %funclet_bb14 - -funclet_bb14: - %cleanuppad = cleanuppad within none [] - br label %bb13 - -unreachable: - unreachable - -bb10: - cleanupret from %cleanuppad5 unwind to caller - -funclet_bb10: - %cleanuppad5 = cleanuppad within none [] - br label %bb10 - -bb13: - cleanupret from %cleanuppad unwind label %funclet_bb10 -} - -declare void @func(i64, i64, ptr) _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
