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[WebAssembly] Add Wasm exception handling prepare pass
Summary: This adds a pass that transforms a program to be prepared for Wasm exception handling. This is using Windows EH instructions and based on the previous Wasm EH proposal. (https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md) Reviewers: dschuff, majnemer Subscribers: jfb, mgorny, sbc100, jgravelle-google, JDevlieghere, sunfish, llvm-commits Differential Revision: https://reviews.llvm.org/D43746 llvm-svn: 333696
This commit is contained in:
Heejin Ahn
parent
46ce3ad2cd
commit
33a1d3d73d
@ -329,13 +329,17 @@ namespace llvm {
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/// createWinEHPass - Prepares personality functions used by MSVC on Windows,
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/// in addition to the Itanium LSDA based personalities.
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FunctionPass *createWinEHPass();
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FunctionPass *createWinEHPass(bool DemoteCatchSwitchPHIOnly = false);
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/// createSjLjEHPreparePass - This pass adapts exception handling code to use
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/// the GCC-style builtin setjmp/longjmp (sjlj) to handling EH control flow.
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///
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FunctionPass *createSjLjEHPreparePass();
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/// createWasmEHPass - This pass adapts exception handling code to use
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/// WebAssembly's exception handling scheme.
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FunctionPass *createWasmEHPass();
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/// LocalStackSlotAllocation - This pass assigns local frame indices to stack
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/// slots relative to one another and allocates base registers to access them
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/// when it is estimated by the target to be out of range of normal frame
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@ -42,7 +42,21 @@ def int_wasm_rethrow : Intrinsic<[], [], [Throws, IntrNoReturn]>;
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// Since wasm does not use landingpad instructions, these instructions return
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// exception pointer and selector values until we lower them in WasmEHPrepare.
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def int_wasm_get_exception : Intrinsic<[llvm_ptr_ty], [], [IntrHasSideEffects]>;
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def int_wasm_get_ehselector : Intrinsic<[llvm_i32_ty], [],
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def int_wasm_get_exception : Intrinsic<[llvm_ptr_ty], [llvm_token_ty],
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[IntrHasSideEffects]>;
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def int_wasm_get_ehselector : Intrinsic<[llvm_i32_ty], [llvm_token_ty],
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[IntrHasSideEffects]>;
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// wasm.catch returns the pointer to the exception object caught by wasm 'catch'
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// instruction.
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def int_wasm_catch : Intrinsic<[llvm_ptr_ty], [llvm_i32_ty],
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[IntrHasSideEffects]>;
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// WebAssembly EH must maintain the landingpads in the order assigned to them
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// by WasmEHPrepare pass to generate landingpad table in EHStreamer. This is
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// used in order to give them the indices in WasmEHPrepare.
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def int_wasm_landingpad_index: Intrinsic<[], [llvm_i32_ty], [IntrNoMem]>;
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// Returns LSDA address of the current function.
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def int_wasm_lsda : Intrinsic<[llvm_ptr_ty], [], [IntrNoMem]>;
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}
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@ -389,6 +389,7 @@ void initializeUnreachableMachineBlockElimPass(PassRegistry&);
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void initializeVerifierLegacyPassPass(PassRegistry&);
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void initializeVirtRegMapPass(PassRegistry&);
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void initializeVirtRegRewriterPass(PassRegistry&);
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void initializeWasmEHPreparePass(PassRegistry&);
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void initializeWholeProgramDevirtPass(PassRegistry&);
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void initializeWinEHPreparePass(PassRegistry&);
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void initializeWriteBitcodePassPass(PassRegistry&);
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@ -158,6 +158,7 @@ add_llvm_library(LLVMCodeGen
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UnreachableBlockElim.cpp
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ValueTypes.cpp
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VirtRegMap.cpp
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WasmEHPrepare.cpp
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WinEHPrepare.cpp
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XRayInstrumentation.cpp
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@ -102,6 +102,7 @@ void llvm::initializeCodeGen(PassRegistry &Registry) {
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initializeUnreachableMachineBlockElimPass(Registry);
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initializeVirtRegMapPass(Registry);
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initializeVirtRegRewriterPass(Registry);
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initializeWasmEHPreparePass(Registry);
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initializeWinEHPreparePass(Registry);
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initializeXRayInstrumentationPass(Registry);
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initializeMIRCanonicalizerPass(Registry);
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@ -656,7 +656,12 @@ void TargetPassConfig::addPassesToHandleExceptions() {
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addPass(createDwarfEHPass());
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break;
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case ExceptionHandling::Wasm:
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// TODO to prevent warning
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// Wasm EH uses Windows EH instructions, but it does not need to demote PHIs
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// on catchpads and cleanuppads because it does not outline them into
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// funclets. Catchswitch blocks are not lowered in SelectionDAG, so we
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// should remove PHIs there.
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addPass(createWinEHPass(/*DemoteCatchSwitchPHIOnly=*/false));
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addPass(createWasmEHPass());
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break;
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case ExceptionHandling::None:
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addPass(createLowerInvokePass());
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331
lib/CodeGen/WasmEHPrepare.cpp
Normal file
331
lib/CodeGen/WasmEHPrepare.cpp
Normal file
@ -0,0 +1,331 @@
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//===-- WasmEHPrepare - Prepare excepton handling for WebAssembly --------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This transformation is designed for use by code generators which use
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// WebAssembly exception handling scheme.
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//
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// WebAssembly exception handling uses Windows exception IR for the middle level
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// representation. This pass does the following transformation for every
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// catchpad block:
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// (In C-style pseudocode)
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//
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// - Before:
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// catchpad ...
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// exn = wasm.get.exception();
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// selector = wasm.get.selector();
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// ...
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//
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// - After:
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// catchpad ...
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// exn = wasm.catch(0); // 0 is a tag for C++
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// wasm.landingpad.index(index);
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// // Only add below in case it's not a single catch (...)
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// __wasm_lpad_context.lpad_index = index;
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// __wasm_lpad_context.lsda = wasm.lsda();
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// _Unwind_CallPersonality(exn);
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// int selector = __wasm.landingpad_context.selector;
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// ...
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//
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// Also, does the following for a cleanuppad block with a call to
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// __clang_call_terminate():
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// - Before:
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// cleanuppad ...
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// exn = wasm.get.exception();
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// __clang_call_terminate(exn);
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//
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// - After:
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// cleanuppad ...
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// exn = wasm.catch(0); // 0 is a tag for C++
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// __clang_call_terminate(exn);
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//
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//
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// * Background: WebAssembly EH instructions
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// WebAssembly's try and catch instructions are structured as follows:
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// try
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// instruction*
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// catch (C++ tag)
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// instruction*
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// ...
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// catch_all
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// instruction*
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// try_end
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//
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// A catch instruction in WebAssembly does not correspond to a C++ catch clause.
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// In WebAssembly, there is a single catch instruction for all C++ exceptions.
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// There can be more catch instructions for exceptions in other languages, but
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// they are not generated for now. catch_all catches all exceptions including
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// foreign exceptions (e.g. JavaScript). We turn catchpads into catch (C++ tag)
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// and cleanuppads into catch_all, with one exception: cleanuppad with a call to
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// __clang_call_terminate should be both in catch (C++ tag) and catch_all.
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//
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//
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// * Background: Direct personality function call
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// In WebAssembly EH, the VM is responsible for unwinding the stack once an
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// exception is thrown. After the stack is unwound, the control flow is
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// transfered to WebAssembly 'catch' instruction, which returns a caught
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// exception object.
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//
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// Unwinding the stack is not done by libunwind but the VM, so the personality
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// function in libcxxabi cannot be called from libunwind during the unwinding
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// process. So after a catch instruction, we insert a call to a wrapper function
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// in libunwind that in turn calls the real personality function.
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//
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// In Itanium EH, if the personality function decides there is no matching catch
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// clause in a call frame and no cleanup action to perform, the unwinder doesn't
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// stop there and continues unwinding. But in Wasm EH, the unwinder stops at
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// every call frame with a catch intruction, after which the personality
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// function is called from the compiler-generated user code here.
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//
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// In libunwind, we have this struct that serves as a communincation channel
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// between the compiler-generated user code and the personality function in
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// libcxxabi.
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//
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// struct _Unwind_LandingPadContext {
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// uintptr_t lpad_index;
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// uintptr_t lsda;
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// uintptr_t selector;
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// };
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// struct _Unwind_LandingPadContext __wasm_lpad_context = ...;
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//
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// And this wrapper in libunwind calls the personality function.
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//
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// _Unwind_Reason_Code _Unwind_CallPersonality(void *exception_ptr) {
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// struct _Unwind_Exception *exception_obj =
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// (struct _Unwind_Exception *)exception_ptr;
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// _Unwind_Reason_Code ret = __gxx_personality_v0(
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// 1, _UA_CLEANUP_PHASE, exception_obj->exception_class, exception_obj,
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// (struct _Unwind_Context *)__wasm_lpad_context);
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// return ret;
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// }
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//
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// We pass a landing pad index, and the address of LSDA for the current function
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// to the wrapper function _Unwind_CallPersonality in libunwind, and we retrieve
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// the selector after it returns.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/ADT/SetVector.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/ADT/Triple.h"
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#include "llvm/CodeGen/Passes.h"
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#include "llvm/CodeGen/TargetLowering.h"
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#include "llvm/CodeGen/TargetSubtargetInfo.h"
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#include "llvm/IR/Dominators.h"
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#include "llvm/IR/IRBuilder.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/Pass.h"
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#include "llvm/Transforms/Utils/BasicBlockUtils.h"
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using namespace llvm;
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#define DEBUG_TYPE "wasmehprepare"
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namespace {
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class WasmEHPrepare : public FunctionPass {
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Type *LPadContextTy = nullptr; // type of 'struct _Unwind_LandingPadContext'
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GlobalVariable *LPadContextGV = nullptr; // __wasm_lpad_context
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// Field addresses of struct _Unwind_LandingPadContext
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Value *LPadIndexField = nullptr; // lpad_index field
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Value *LSDAField = nullptr; // lsda field
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Value *SelectorField = nullptr; // selector
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Function *CatchF = nullptr; // wasm.catch.extract() intrinsic
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Function *LPadIndexF = nullptr; // wasm.landingpad.index() intrinsic
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Function *LSDAF = nullptr; // wasm.lsda() intrinsic
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Function *GetExnF = nullptr; // wasm.get.exception() intrinsic
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Function *GetSelectorF = nullptr; // wasm.get.ehselector() intrinsic
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Function *CallPersonalityF = nullptr; // _Unwind_CallPersonality() wrapper
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Function *ClangCallTermF = nullptr; // __clang_call_terminate() function
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void prepareEHPad(BasicBlock *BB, unsigned Index);
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void prepareTerminateCleanupPad(BasicBlock *BB);
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public:
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static char ID; // Pass identification, replacement for typeid
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WasmEHPrepare() : FunctionPass(ID) {}
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bool doInitialization(Module &M) override;
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bool runOnFunction(Function &F) override;
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StringRef getPassName() const override {
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return "WebAssembly Exception handling preparation";
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}
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};
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} // end anonymous namespace
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char WasmEHPrepare::ID = 0;
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INITIALIZE_PASS(WasmEHPrepare, DEBUG_TYPE, "Prepare WebAssembly exceptions",
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false, false);
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FunctionPass *llvm::createWasmEHPass() { return new WasmEHPrepare(); }
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bool WasmEHPrepare::doInitialization(Module &M) {
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IRBuilder<> IRB(M.getContext());
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LPadContextTy = StructType::get(IRB.getInt32Ty(), // lpad_index
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IRB.getInt8PtrTy(), // lsda
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IRB.getInt32Ty() // selector
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);
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return false;
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}
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bool WasmEHPrepare::runOnFunction(Function &F) {
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SmallVector<BasicBlock *, 16> CatchPads;
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SmallVector<BasicBlock *, 16> CleanupPads;
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for (BasicBlock &BB : F) {
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if (!BB.isEHPad())
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continue;
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auto *Pad = BB.getFirstNonPHI();
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if (isa<CatchPadInst>(Pad))
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CatchPads.push_back(&BB);
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else if (isa<CleanupPadInst>(Pad))
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CleanupPads.push_back(&BB);
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}
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if (CatchPads.empty() && CleanupPads.empty())
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return false;
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assert(F.hasPersonalityFn() && "Personality function not found");
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Module &M = *F.getParent();
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IRBuilder<> IRB(F.getContext());
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// __wasm_lpad_context global variable
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LPadContextGV = cast<GlobalVariable>(
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M.getOrInsertGlobal("__wasm_lpad_context", LPadContextTy));
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LPadIndexField = IRB.CreateConstGEP2_32(LPadContextTy, LPadContextGV, 0, 0,
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"lpad_index_gep");
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LSDAField =
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IRB.CreateConstGEP2_32(LPadContextTy, LPadContextGV, 0, 1, "lsda_gep");
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SelectorField = IRB.CreateConstGEP2_32(LPadContextTy, LPadContextGV, 0, 2,
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"selector_gep");
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// wasm.catch() intinsic, which will be lowered to wasm 'catch' instruction.
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CatchF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_catch);
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// wasm.landingpad.index() intrinsic, which is to specify landingpad index
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LPadIndexF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_landingpad_index);
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// wasm.lsda() intrinsic. Returns the address of LSDA table for the current
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// function.
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LSDAF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_lsda);
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// wasm.get.exception() and wasm.get.ehselector() intrinsics. Calls to these
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// are generated in clang.
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GetExnF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_get_exception);
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GetSelectorF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_get_ehselector);
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// _Unwind_CallPersonality() wrapper function, which calls the personality
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CallPersonalityF = cast<Function>(M.getOrInsertFunction(
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"_Unwind_CallPersonality", IRB.getInt32Ty(), IRB.getInt8PtrTy()));
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CallPersonalityF->setDoesNotThrow();
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// __clang_call_terminate() function, which is inserted by clang in case a
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// cleanup throws
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ClangCallTermF = M.getFunction("__clang_call_terminate");
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unsigned Index = 0;
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for (auto *BB : CatchPads) {
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auto *CPI = cast<CatchPadInst>(BB->getFirstNonPHI());
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// In case of a single catch (...), we don't need to emit LSDA
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if (CPI->getNumArgOperands() == 1 &&
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cast<Constant>(CPI->getArgOperand(0))->isNullValue())
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prepareEHPad(BB, -1);
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else
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prepareEHPad(BB, Index++);
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}
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if (!ClangCallTermF)
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return !CatchPads.empty();
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// Cleanuppads will turn into catch_all later, but cleanuppads with a call to
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// __clang_call_terminate() is a special case. __clang_call_terminate() takes
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// an exception object, so we have to duplicate call in both 'catch <C++ tag>'
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// and 'catch_all' clauses. Here we only insert a call to catch; the
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// duplication will be done later. In catch_all, the exception object will be
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// set to null.
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for (auto *BB : CleanupPads)
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for (auto &I : *BB)
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if (auto *CI = dyn_cast<CallInst>(&I))
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if (CI->getCalledValue() == ClangCallTermF)
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prepareEHPad(BB, -1);
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return true;
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}
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void WasmEHPrepare::prepareEHPad(BasicBlock *BB, unsigned Index) {
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assert(BB->isEHPad() && "BB is not an EHPad!");
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IRBuilder<> IRB(BB->getContext());
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IRB.SetInsertPoint(&*BB->getFirstInsertionPt());
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// The argument to wasm.catch() is the tag for C++ exceptions, which we set to
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// 0 for this module.
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// Pseudocode: void *exn = wasm.catch(0);
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Instruction *Exn = IRB.CreateCall(CatchF, IRB.getInt32(0), "exn");
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// Replace the return value of wasm.get.exception() with the return value from
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// wasm.catch().
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auto *FPI = cast<FuncletPadInst>(BB->getFirstNonPHI());
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Instruction *GetExnCI = nullptr, *GetSelectorCI = nullptr;
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for (auto &U : FPI->uses()) {
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if (auto *CI = dyn_cast<CallInst>(U.getUser())) {
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if (CI->getCalledValue() == GetExnF)
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GetExnCI = CI;
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else if (CI->getCalledValue() == GetSelectorF)
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GetSelectorCI = CI;
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}
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}
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assert(GetExnCI && "wasm.get.exception() call does not exist");
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GetExnCI->replaceAllUsesWith(Exn);
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GetExnCI->eraseFromParent();
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// In case it is a catchpad with single catch (...) or a cleanuppad, we don't
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// need to call personality function because we don't need a selector.
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if (FPI->getNumArgOperands() == 0 ||
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(FPI->getNumArgOperands() == 1 &&
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cast<Constant>(FPI->getArgOperand(0))->isNullValue())) {
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if (GetSelectorCI) {
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assert(GetSelectorCI->use_empty() &&
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"wasm.get.ehselector() still has uses!");
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GetSelectorCI->eraseFromParent();
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}
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return;
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}
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IRB.SetInsertPoint(Exn->getNextNode());
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// This is to create a map of <landingpad EH label, landingpad index> in
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// SelectionDAGISel, which is to be used in EHStreamer to emit LSDA tables.
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// Pseudocode: wasm.landingpad.index(Index);
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IRB.CreateCall(LPadIndexF, IRB.getInt32(Index));
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// Pseudocode: __wasm_lpad_context.lpad_index = index;
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IRB.CreateStore(IRB.getInt32(Index), LPadIndexField);
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// Store LSDA address only if this catchpad belongs to a top-level
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// catchswitch. If there is another catchpad that dominates this pad, we don't
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// need to store LSDA address again, because they are the same throughout the
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// function and have been already stored before.
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// TODO Can we not store LSDA address in user function but make libcxxabi
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// compute it?
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auto *CPI = cast<CatchPadInst>(FPI);
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if (isa<ConstantTokenNone>(CPI->getCatchSwitch()->getParentPad()))
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// Pseudocode: __wasm_lpad_context.lsda = wasm.lsda();
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||||
IRB.CreateStore(IRB.CreateCall(LSDAF), LSDAField);
|
||||
|
||||
// Pseudocode: _Unwind_CallPersonality(exn);
|
||||
CallInst *PersCI =
|
||||
IRB.CreateCall(CallPersonalityF, Exn, OperandBundleDef("funclet", CPI));
|
||||
PersCI->setDoesNotThrow();
|
||||
|
||||
// Pseudocode: int selector = __wasm.landingpad_context.selector;
|
||||
Instruction *Selector = IRB.CreateLoad(SelectorField, "selector");
|
||||
|
||||
// Replace the return value from wasm.get.ehselector() with the selector value
|
||||
// loaded from __wasm_lpad_context.selector.
|
||||
assert(GetSelectorCI && "wasm.get.ehselector() call does not exist");
|
||||
GetSelectorCI->replaceAllUsesWith(Selector);
|
||||
GetSelectorCI->eraseFromParent();
|
||||
}
|
||||
@ -49,12 +49,17 @@ static cl::opt<bool> DisableCleanups(
|
||||
cl::desc("Do not remove implausible terminators or other similar cleanups"),
|
||||
cl::init(false));
|
||||
|
||||
static cl::opt<bool> DemoteCatchSwitchPHIOnlyOpt(
|
||||
"demote-catchswitch-only", cl::Hidden,
|
||||
cl::desc("Demote catchswitch BBs only (for wasm EH)"), cl::init(false));
|
||||
|
||||
namespace {
|
||||
|
||||
class WinEHPrepare : public FunctionPass {
|
||||
public:
|
||||
static char ID; // Pass identification, replacement for typeid.
|
||||
WinEHPrepare() : FunctionPass(ID) {}
|
||||
WinEHPrepare(bool DemoteCatchSwitchPHIOnly = false)
|
||||
: FunctionPass(ID), DemoteCatchSwitchPHIOnly(DemoteCatchSwitchPHIOnly) {}
|
||||
|
||||
bool runOnFunction(Function &Fn) override;
|
||||
|
||||
@ -77,12 +82,14 @@ private:
|
||||
bool prepareExplicitEH(Function &F);
|
||||
void colorFunclets(Function &F);
|
||||
|
||||
void demotePHIsOnFunclets(Function &F);
|
||||
void demotePHIsOnFunclets(Function &F, bool DemoteCatchSwitchPHIOnly);
|
||||
void cloneCommonBlocks(Function &F);
|
||||
void removeImplausibleInstructions(Function &F);
|
||||
void cleanupPreparedFunclets(Function &F);
|
||||
void verifyPreparedFunclets(Function &F);
|
||||
|
||||
bool DemoteCatchSwitchPHIOnly;
|
||||
|
||||
// All fields are reset by runOnFunction.
|
||||
EHPersonality Personality = EHPersonality::Unknown;
|
||||
|
||||
@ -97,7 +104,9 @@ char WinEHPrepare::ID = 0;
|
||||
INITIALIZE_PASS(WinEHPrepare, DEBUG_TYPE, "Prepare Windows exceptions",
|
||||
false, false)
|
||||
|
||||
FunctionPass *llvm::createWinEHPass() { return new WinEHPrepare(); }
|
||||
FunctionPass *llvm::createWinEHPass(bool DemoteCatchSwitchPHIOnly) {
|
||||
return new WinEHPrepare(DemoteCatchSwitchPHIOnly);
|
||||
}
|
||||
|
||||
bool WinEHPrepare::runOnFunction(Function &Fn) {
|
||||
if (!Fn.hasPersonalityFn())
|
||||
@ -678,13 +687,17 @@ void WinEHPrepare::colorFunclets(Function &F) {
|
||||
}
|
||||
}
|
||||
|
||||
void WinEHPrepare::demotePHIsOnFunclets(Function &F) {
|
||||
void WinEHPrepare::demotePHIsOnFunclets(Function &F,
|
||||
bool DemoteCatchSwitchPHIOnly) {
|
||||
// Strip PHI nodes off of EH pads.
|
||||
SmallVector<PHINode *, 16> PHINodes;
|
||||
for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE;) {
|
||||
BasicBlock *BB = &*FI++;
|
||||
if (!BB->isEHPad())
|
||||
continue;
|
||||
if (DemoteCatchSwitchPHIOnly && !isa<CatchSwitchInst>(BB->getFirstNonPHI()))
|
||||
continue;
|
||||
|
||||
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE;) {
|
||||
Instruction *I = &*BI++;
|
||||
auto *PN = dyn_cast<PHINode>(I);
|
||||
@ -1032,7 +1045,8 @@ bool WinEHPrepare::prepareExplicitEH(Function &F) {
|
||||
cloneCommonBlocks(F);
|
||||
|
||||
if (!DisableDemotion)
|
||||
demotePHIsOnFunclets(F);
|
||||
demotePHIsOnFunclets(F, DemoteCatchSwitchPHIOnly ||
|
||||
DemoteCatchSwitchPHIOnlyOpt);
|
||||
|
||||
if (!DisableCleanups) {
|
||||
LLVM_DEBUG(verifyFunction(F));
|
||||
|
||||
317
test/CodeGen/WebAssembly/wasmehprepare.ll
Normal file
317
test/CodeGen/WebAssembly/wasmehprepare.ll
Normal file
@ -0,0 +1,317 @@
|
||||
; RUN: opt < %s -winehprepare -demote-catchswitch-only -wasmehprepare -S | FileCheck %s
|
||||
|
||||
target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
|
||||
target triple = "wasm32-unknown-unknown"
|
||||
|
||||
; CHECK: @__wasm_lpad_context = external global { i32, i8*, i32 }
|
||||
|
||||
@_ZTIi = external constant i8*
|
||||
%struct.Cleanup = type { i8 }
|
||||
|
||||
; A single 'catch (int)' clause.
|
||||
; A wasm.catch() call, wasm.lsda() call, and personality call to generate a
|
||||
; selector should all be genereated after the catchpad.
|
||||
define void @test0() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
|
||||
; CHECK-LABEL: @test0()
|
||||
entry:
|
||||
invoke void @foo()
|
||||
to label %try.cont unwind label %catch.dispatch
|
||||
|
||||
catch.dispatch: ; preds = %entry
|
||||
%0 = catchswitch within none [label %catch.start] unwind to caller
|
||||
|
||||
catch.start: ; preds = %catch.dispatch
|
||||
%1 = catchpad within %0 [i8* bitcast (i8** @_ZTIi to i8*)]
|
||||
%2 = call i8* @llvm.wasm.get.exception(token %1)
|
||||
%3 = call i32 @llvm.wasm.get.ehselector(token %1)
|
||||
%4 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*))
|
||||
%matches = icmp eq i32 %3, %4
|
||||
br i1 %matches, label %catch, label %rethrow
|
||||
; CHECK: catch.start:
|
||||
; CHECK-NEXT: %[[CATCHPAD:.*]] = catchpad
|
||||
; CHECK-NEXT: %[[EXN:.*]] = call i8* @llvm.wasm.catch(i32 0)
|
||||
; CHECK-NEXT: call void @llvm.wasm.landingpad.index(i32 0)
|
||||
; CHECK-NEXT: store i32 0, i32* getelementptr inbounds ({ i32, i8*, i32 }, { i32, i8*, i32 }* @__wasm_lpad_context, i32 0, i32 0)
|
||||
; CHECK-NEXT: %[[LSDA:.*]] = call i8* @llvm.wasm.lsda()
|
||||
; CHECK-NEXT: store i8* %[[LSDA]], i8** getelementptr inbounds ({ i32, i8*, i32 }, { i32, i8*, i32 }* @__wasm_lpad_context, i32 0, i32 1)
|
||||
; CHECK-NEXT: call i32 @_Unwind_CallPersonality(i8* %[[EXN]]) {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
|
||||
; CHECK-NEXT: %[[SELECTOR:.*]] = load i32, i32* getelementptr inbounds ({ i32, i8*, i32 }, { i32, i8*, i32 }* @__wasm_lpad_context, i32 0, i32 2)
|
||||
; CHECK: icmp eq i32 %[[SELECTOR]]
|
||||
|
||||
catch: ; preds = %catch.start
|
||||
%5 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
|
||||
call void @__cxa_end_catch() [ "funclet"(token %1) ]
|
||||
catchret from %1 to label %try.cont
|
||||
; CHECK: catch:
|
||||
; CHECK-NEXT: call i8* @__cxa_begin_catch(i8* %[[EXN]])
|
||||
|
||||
rethrow: ; preds = %catch.start
|
||||
call void @__cxa_rethrow() [ "funclet"(token %1) ]
|
||||
unreachable
|
||||
|
||||
try.cont: ; preds = %entry, %catch
|
||||
ret void
|
||||
}
|
||||
|
||||
; Two try-catches, one of them is with a single 'catch (...)' clause.
|
||||
; For the catchpad with a single 'catch (...)', only a wasm.catch() call should
|
||||
; be generated after the catchpad; wasm.landingpad.index() and personality call
|
||||
; should NOT be generated. For the other catchpad, the argument of
|
||||
; wasm.landingpad.index() should be not 1 but 0.
|
||||
define void @test1() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
|
||||
; CHECK-LABEL: @test1()
|
||||
entry:
|
||||
invoke void @foo()
|
||||
to label %try.cont unwind label %catch.dispatch
|
||||
|
||||
catch.dispatch: ; preds = %entry
|
||||
%0 = catchswitch within none [label %catch.start] unwind to caller
|
||||
|
||||
catch.start: ; preds = %catch.dispatch
|
||||
%1 = catchpad within %0 [i8* null]
|
||||
%2 = call i8* @llvm.wasm.get.exception(token %1)
|
||||
%3 = call i32 @llvm.wasm.get.ehselector(token %1)
|
||||
%4 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
|
||||
call void @__cxa_end_catch() [ "funclet"(token %1) ]
|
||||
catchret from %1 to label %try.cont
|
||||
; CHECK: catch.start:
|
||||
; CHECK-NEXT: catchpad within %0 [i8* null]
|
||||
; CHECK-NEXT: call i8* @llvm.wasm.catch(i32 0)
|
||||
; CHECK-NOT: call void @llvm.wasm.landingpad.index
|
||||
; CHECK-NOT: store {{.*}} @__wasm_lpad_context
|
||||
; CHECK-NOT: call i8* @llvm.wasm.lsda()
|
||||
; CHECK-NOT: call i32 @_Unwind_CallPersonality
|
||||
; CHECK-NOT: load {{.*}} @__wasm_lpad_context
|
||||
|
||||
try.cont: ; preds = %entry, %catch.start
|
||||
invoke void @foo()
|
||||
to label %try.cont7 unwind label %catch.dispatch2
|
||||
|
||||
catch.dispatch2: ; preds = %try.cont
|
||||
%5 = catchswitch within none [label %catch.start3] unwind to caller
|
||||
|
||||
catch.start3: ; preds = %catch.dispatch2
|
||||
%6 = catchpad within %5 [i8* bitcast (i8** @_ZTIi to i8*)]
|
||||
%7 = call i8* @llvm.wasm.get.exception(token %6)
|
||||
%8 = call i32 @llvm.wasm.get.ehselector(token %6)
|
||||
%9 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*))
|
||||
%matches = icmp eq i32 %8, %9
|
||||
br i1 %matches, label %catch4, label %rethrow
|
||||
; CHECK: catch.start3:
|
||||
; CHECK: call void @llvm.wasm.landingpad.index(i32 0)
|
||||
|
||||
catch4: ; preds = %catch.start3
|
||||
%10 = call i8* @__cxa_begin_catch(i8* %7) [ "funclet"(token %6) ]
|
||||
call void @__cxa_end_catch() [ "funclet"(token %6) ]
|
||||
catchret from %6 to label %try.cont7
|
||||
|
||||
rethrow: ; preds = %catch.start3
|
||||
call void @__cxa_rethrow() [ "funclet"(token %6) ]
|
||||
unreachable
|
||||
|
||||
try.cont7: ; preds = %try.cont, %catch4
|
||||
ret void
|
||||
}
|
||||
|
||||
; A nested try-catch within a catch. Within the nested catchpad, wasm.lsda()
|
||||
; call should NOT be generated.
|
||||
define void @test2() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
|
||||
; CHECK-LABEL: @test2()
|
||||
entry:
|
||||
invoke void @foo()
|
||||
to label %try.cont9 unwind label %catch.dispatch
|
||||
|
||||
catch.dispatch: ; preds = %entry
|
||||
%0 = catchswitch within none [label %catch.start] unwind to caller
|
||||
|
||||
catch.start: ; preds = %catch.dispatch
|
||||
%1 = catchpad within %0 [i8* bitcast (i8** @_ZTIi to i8*)]
|
||||
%2 = call i8* @llvm.wasm.get.exception(token %1)
|
||||
%3 = call i32 @llvm.wasm.get.ehselector(token %1)
|
||||
%4 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*))
|
||||
%matches = icmp eq i32 %3, %4
|
||||
br i1 %matches, label %catch, label %rethrow
|
||||
; CHECK: catch.start:
|
||||
; CHECK: call i8* @llvm.wasm.lsda()
|
||||
|
||||
catch: ; preds = %catch.start
|
||||
%5 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
|
||||
invoke void @foo() [ "funclet"(token %1) ]
|
||||
to label %try.cont unwind label %catch.dispatch2
|
||||
|
||||
catch.dispatch2: ; preds = %catch
|
||||
%6 = catchswitch within %1 [label %catch.start3] unwind label %ehcleanup
|
||||
|
||||
catch.start3: ; preds = %catch.dispatch2
|
||||
%7 = catchpad within %6 [i8* bitcast (i8** @_ZTIi to i8*)]
|
||||
%8 = call i8* @llvm.wasm.get.exception(token %7)
|
||||
%9 = call i32 @llvm.wasm.get.ehselector(token %7)
|
||||
%10 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*))
|
||||
%matches4 = icmp eq i32 %9, %10
|
||||
br i1 %matches4, label %catch6, label %rethrow5
|
||||
; CHECK: catch.start3:
|
||||
; CHECK-NOT: call i8* @llvm.wasm.lsda()
|
||||
|
||||
catch6: ; preds = %catch.start3
|
||||
%11 = call i8* @__cxa_begin_catch(i8* %8) [ "funclet"(token %7) ]
|
||||
call void @__cxa_end_catch() [ "funclet"(token %7) ]
|
||||
catchret from %7 to label %try.cont
|
||||
|
||||
rethrow5: ; preds = %catch.start3
|
||||
invoke void @__cxa_rethrow() [ "funclet"(token %7) ]
|
||||
to label %unreachable unwind label %ehcleanup
|
||||
|
||||
try.cont: ; preds = %catch, %catch6
|
||||
call void @__cxa_end_catch() [ "funclet"(token %1) ]
|
||||
catchret from %1 to label %try.cont9
|
||||
|
||||
rethrow: ; preds = %catch.start
|
||||
call void @__cxa_rethrow() [ "funclet"(token %1) ]
|
||||
unreachable
|
||||
|
||||
try.cont9: ; preds = %entry, %try.cont
|
||||
ret void
|
||||
|
||||
ehcleanup: ; preds = %rethrow5, %catch.dispatch2
|
||||
%12 = cleanuppad within %1 []
|
||||
call void @__cxa_end_catch() [ "funclet"(token %12) ]
|
||||
cleanupret from %12 unwind to caller
|
||||
; CHECK: ehcleanup:
|
||||
; CHECK-NEXT: cleanuppad
|
||||
; CHECK-NOT: call i8* @llvm.wasm.catch(i32 0)
|
||||
; CHECK-NOT: call void @llvm.wasm.landingpad.index
|
||||
; CHECK-NOT: store {{.*}} @__wasm_lpad_context
|
||||
; CHECK-NOT: call i8* @llvm.wasm.lsda()
|
||||
; CHECK-NOT: call i32 @_Unwind_CallPersonality
|
||||
; CHECK-NOT: load {{.*}} @__wasm_lpad_context
|
||||
|
||||
unreachable: ; preds = %rethrow5
|
||||
unreachable
|
||||
}
|
||||
|
||||
; A cleanuppad with a call to __clang_call_terminate().
|
||||
; A call to wasm.catch() should be generated after the cleanuppad.
|
||||
define hidden void @test3() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
|
||||
; CHECK-LABEL: @test3
|
||||
entry:
|
||||
invoke void @foo()
|
||||
to label %try.cont unwind label %catch.dispatch
|
||||
|
||||
catch.dispatch: ; preds = %entry
|
||||
%0 = catchswitch within none [label %catch.start] unwind to caller
|
||||
|
||||
catch.start: ; preds = %catch.dispatch
|
||||
%1 = catchpad within %0 [i8* null]
|
||||
%2 = call i8* @llvm.wasm.get.exception(token %1)
|
||||
%3 = call i32 @llvm.wasm.get.ehselector(token %1)
|
||||
%4 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
|
||||
invoke void @foo() [ "funclet"(token %1) ]
|
||||
to label %invoke.cont1 unwind label %ehcleanup
|
||||
|
||||
invoke.cont1: ; preds = %catch.start
|
||||
call void @__cxa_end_catch() [ "funclet"(token %1) ]
|
||||
catchret from %1 to label %try.cont
|
||||
|
||||
try.cont: ; preds = %entry, %invoke.cont1
|
||||
ret void
|
||||
|
||||
ehcleanup: ; preds = %catch.start
|
||||
%5 = cleanuppad within %1 []
|
||||
invoke void @__cxa_end_catch() [ "funclet"(token %5) ]
|
||||
to label %invoke.cont2 unwind label %terminate
|
||||
|
||||
invoke.cont2: ; preds = %ehcleanup
|
||||
cleanupret from %5 unwind to caller
|
||||
|
||||
terminate: ; preds = %ehcleanup
|
||||
%6 = cleanuppad within %5 []
|
||||
%7 = call i8* @llvm.wasm.get.exception(token %6)
|
||||
call void @__clang_call_terminate(i8* %7) [ "funclet"(token %6) ]
|
||||
unreachable
|
||||
; CHECK: terminate:
|
||||
; CHECK-NEXT: cleanuppad
|
||||
; CHECK-NEXT: %[[EXN:.*]] = call i8* @llvm.wasm.catch(i32 0)
|
||||
; CHECK-NEXT: call void @__clang_call_terminate(i8* %[[EXN]])
|
||||
}
|
||||
|
||||
; PHI demotion test. Only the phi before catchswitch should be demoted; the phi
|
||||
; before cleanuppad should NOT.
|
||||
define void @test5() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
|
||||
; CHECK-LABEL: @test5
|
||||
entry:
|
||||
%c = alloca %struct.Cleanup, align 1
|
||||
invoke void @foo()
|
||||
to label %invoke.cont unwind label %ehcleanup
|
||||
|
||||
invoke.cont: ; preds = %entry
|
||||
invoke void @foo()
|
||||
to label %invoke.cont1 unwind label %ehcleanup
|
||||
|
||||
invoke.cont1: ; preds = %invoke.cont
|
||||
%call = call %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* %c)
|
||||
br label %try.cont
|
||||
|
||||
ehcleanup: ; preds = %invoke.cont, %entry
|
||||
%num.0 = phi i32 [ 2, %invoke.cont ], [ 1, %entry ]
|
||||
%0 = cleanuppad within none []
|
||||
%call2 = call %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* %c) [ "funclet"(token %0) ]
|
||||
cleanupret from %0 unwind label %catch.dispatch
|
||||
; CHECK: ehcleanup:
|
||||
; CHECK-NEXT: = phi
|
||||
|
||||
catch.dispatch: ; preds = %ehcleanup
|
||||
%1 = catchswitch within none [label %catch.start] unwind to caller
|
||||
|
||||
catch.start: ; preds = %catch.dispatch
|
||||
%2 = catchpad within %1 [i8* null]
|
||||
%3 = call i8* @llvm.wasm.get.exception(token %2)
|
||||
%4 = call i32 @llvm.wasm.get.ehselector(token %2)
|
||||
%5 = call i8* @__cxa_begin_catch(i8* %3) [ "funclet"(token %2) ]
|
||||
call void @func(i32 %num.0) [ "funclet"(token %2) ]
|
||||
call void @__cxa_end_catch() [ "funclet"(token %2) ]
|
||||
catchret from %2 to label %try.cont
|
||||
|
||||
try.cont: ; preds = %catch.start, %invoke.cont1
|
||||
invoke void @foo()
|
||||
to label %invoke.cont3 unwind label %catch.dispatch5
|
||||
|
||||
invoke.cont3: ; preds = %try.cont
|
||||
invoke void @foo()
|
||||
to label %try.cont10 unwind label %catch.dispatch5
|
||||
|
||||
catch.dispatch5: ; preds = %invoke.cont3, %try.cont
|
||||
%num.1 = phi i32 [ 2, %invoke.cont3 ], [ 1, %try.cont ]
|
||||
%6 = catchswitch within none [label %catch.start6] unwind to caller
|
||||
; CHECK: catch.dispatch5:
|
||||
; CHECK-NOT: = phi
|
||||
|
||||
catch.start6: ; preds = %catch.dispatch5
|
||||
%7 = catchpad within %6 [i8* null]
|
||||
%8 = call i8* @llvm.wasm.get.exception(token %7)
|
||||
%9 = call i32 @llvm.wasm.get.ehselector(token %7)
|
||||
%10 = call i8* @__cxa_begin_catch(i8* %8) [ "funclet"(token %7) ]
|
||||
call void @func(i32 %num.1) [ "funclet"(token %7) ]
|
||||
call void @__cxa_end_catch() [ "funclet"(token %7) ]
|
||||
catchret from %7 to label %try.cont10
|
||||
|
||||
try.cont10: ; preds = %invoke.cont3, %catch.start6
|
||||
ret void
|
||||
}
|
||||
|
||||
declare void @foo()
|
||||
declare void @func(i32)
|
||||
declare %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* returned)
|
||||
declare i32 @__gxx_wasm_personality_v0(...)
|
||||
declare i8* @llvm.wasm.get.exception(token)
|
||||
declare i32 @llvm.wasm.get.ehselector(token)
|
||||
declare i32 @llvm.eh.typeid.for(i8*)
|
||||
declare i8* @__cxa_begin_catch(i8*)
|
||||
declare void @__cxa_end_catch()
|
||||
declare void @__cxa_rethrow()
|
||||
declare void @__clang_call_terminate(i8*)
|
||||
|
||||
; CHECK-DAG: declare i8* @llvm.wasm.catch(i32)
|
||||
; CHECK-DAG: declare void @llvm.wasm.landingpad.index(i32)
|
||||
; CHECK-DAG: declare i8* @llvm.wasm.lsda()
|
||||
; CHECK-DAG: declare i32 @_Unwind_CallPersonality(i8*)
|
||||
|
||||
@ -447,6 +447,7 @@ int main(int argc, char **argv) {
|
||||
initializePostInlineEntryExitInstrumenterPass(Registry);
|
||||
initializeUnreachableBlockElimLegacyPassPass(Registry);
|
||||
initializeExpandReductionsPass(Registry);
|
||||
initializeWasmEHPreparePass(Registry);
|
||||
initializeWriteBitcodePassPass(Registry);
|
||||
|
||||
#ifdef LINK_POLLY_INTO_TOOLS
|
||||
|
||||
Loading…
Reference in New Issue
Block a user