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|
; RUN: not llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-keep-registers -exception-model=wasm
; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -exception-model=wasm -mattr=+exception-handling -verify-machineinstrs | FileCheck -allow-deprecated-dag-overlap %s
; RUN: llc < %s -disable-wasm-fallthrough-return-opt -wasm-keep-registers -exception-model=wasm -mattr=+exception-handling
target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
target triple = "wasm32-unknown-unknown"
%struct.Temp = type { i8 }
@_ZTIi = external constant i8*
; CHECK-LABEL: test_throw:
; CHECK: throw __cpp_exception, $0
; CHECK-NOT: unreachable
define void @test_throw(i8* %p) {
call void @llvm.wasm.throw(i32 0, i8* %p)
ret void
}
; Simple test with a try-catch
;
; void foo();
; void test_catch() {
; try {
; foo();
; } catch (int) {
; }
; }
; CHECK-LABEL: test_catch:
; CHECK: global.get ${{.+}}=, __stack_pointer
; CHECK: try
; CHECK: call foo
; CHECK: catch $[[EXNREF:[0-9]+]]=
; CHECK: global.set __stack_pointer
; CHECK: block i32
; CHECK: br_on_exn 0, __cpp_exception, $[[EXNREF]]
; CHECK: rethrow $[[EXNREF]]
; CHECK: end_block
; CHECK: extract_exception $[[EXN:[0-9]+]]=
; CHECK-DAG: i32.store __wasm_lpad_context
; CHECK-DAG: i32.store __wasm_lpad_context+4
; CHECK: i32.call $drop=, _Unwind_CallPersonality, $[[EXN]]
; CHECK: block
; CHECK: br_if 0
; CHECK: i32.call $drop=, __cxa_begin_catch
; CHECK: call __cxa_end_catch
; CHECK: br 1
; CHECK: end_block
; CHECK: rethrow $[[EXNREF]]
; CHECK: end_try
define void @test_catch() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
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
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
rethrow: ; preds = %catch.start
call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
unreachable
try.cont: ; preds = %entry, %catch
ret void
}
; Destructor (cleanup) test
;
; void foo();
; struct Temp {
; ~Temp() {}
; };
; void test_cleanup() {
; Temp t;
; foo();
; }
; CHECK-LABEL: test_cleanup:
; CHECK: try
; CHECK: call foo
; CHECK: catch $[[EXNREF:[0-9]+]]=
; CHECK: global.set __stack_pointer
; CHECK: i32.call $drop=, _ZN4TempD2Ev
; CHECK: rethrow $[[EXNREF]]
; CHECK: end_try
define void @test_cleanup() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
entry:
%t = alloca %struct.Temp, align 1
invoke void @foo()
to label %invoke.cont unwind label %ehcleanup
invoke.cont: ; preds = %entry
%call = call %struct.Temp* @_ZN4TempD2Ev(%struct.Temp* %t)
ret void
ehcleanup: ; preds = %entry
%0 = cleanuppad within none []
%call1 = call %struct.Temp* @_ZN4TempD2Ev(%struct.Temp* %t) [ "funclet"(token %0) ]
cleanupret from %0 unwind to caller
}
; Calling a function that may throw within a 'catch (...)' generates a
; temrinatepad, because __cxa_end_catch() also can throw within 'catch (...)'.
;
; void foo();
; void test_terminatepad() {
; try {
; foo();
; } catch (...) {
; foo();
; }
; }
; CHECK-LABEL: test_terminatepad
; CHECK: try
; CHECK: call foo
; CHECK: catch
; CHECK: i32.call $drop=, __cxa_begin_catch
; CHECK: try
; CHECK: call foo
; CHECK: catch
; CHECK: try
; CHECK: call __cxa_end_catch
; CHECK: catch
; CHECK: block i32
; CHECK: br_on_exn 0, __cpp_exception
; CHECK: i32.const ${{.*}}=, 0
; CHECK: call __clang_call_terminate
; CHECK: unreachable
; CHECK: end_block
; CHECK: call __clang_call_terminate
; CHECK: unreachable
; CHECK: end_try
; CHECK: rethrow
; CHECK: end_try
; CHECK: call __cxa_end_catch
; CHECK: end_try
define void @test_terminatepad() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
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
}
; Tests prologues and epilogues are not generated within EH scopes.
; They should not be treated as funclets; BBs starting with a catch instruction
; should not have a prologue, and BBs ending with a catchret/cleanupret should
; not have an epilogue. This is separate from __stack_pointer restoring
; instructions after a catch instruction.
;
; void bar(int) noexcept;
; void test_no_prolog_epilog_in_ehpad() {
; int stack_var = 0;
; bar(stack_var);
; try {
; foo();
; } catch (int) {
; foo();
; }
; }
; CHECK-LABEL: test_no_prolog_epilog_in_ehpad
; CHECK: try
; CHECK: call foo
; CHECK: catch
; CHECK-NOT: global.get $push{{.+}}=, __stack_pointer
; CHECK: global.set __stack_pointer
; CHECK: block
; CHECK: block
; CHECK: br_if 0
; CHECK: i32.call $drop=, __cxa_begin_catch
; CHECK: try
; CHECK: call foo
; CHECK: catch
; CHECK-NOT: global.get $push{{.+}}=, __stack_pointer
; CHECK: global.set __stack_pointer
; CHECK: call __cxa_end_catch
; CHECK: rethrow
; CHECK-NOT: global.set __stack_pointer, $pop{{.+}}
; CHECK: end_try
; CHECK: end_block
; CHECK: rethrow
; CHECK: end_block
; CHECK-NOT: global.set __stack_pointer, $pop{{.+}}
; CHECK: call __cxa_end_catch
; CHECK: end_try
define void @test_no_prolog_epilog_in_ehpad() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
entry:
%stack_var = alloca i32, align 4
call void @bar(i32* %stack_var)
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
catch: ; preds = %catch.start
%5 = call i8* @__cxa_begin_catch(i8* %2) [ "funclet"(token %1) ]
%6 = bitcast i8* %5 to float*
%7 = load float, float* %6, align 4
invoke void @foo() [ "funclet"(token %1) ]
to label %invoke.cont1 unwind label %ehcleanup
invoke.cont1: ; preds = %catch
call void @__cxa_end_catch() [ "funclet"(token %1) ]
catchret from %1 to label %try.cont
rethrow: ; preds = %catch.start
call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
unreachable
try.cont: ; preds = %entry, %invoke.cont1
ret void
ehcleanup: ; preds = %catch
%8 = cleanuppad within %1 []
call void @__cxa_end_catch() [ "funclet"(token %8) ]
cleanupret from %8 unwind to caller
}
; When a function does not have stack-allocated objects, it does not need to
; store SP back to __stack_pointer global at the epilog.
;
; void foo();
; void test_no_sp_writeback() {
; try {
; foo();
; } catch (...) {
; }
; }
; CHECK-LABEL: test_no_sp_writeback
; CHECK: try
; CHECK: call foo
; CHECK: catch
; CHECK: i32.call $drop=, __cxa_begin_catch
; CHECK: call __cxa_end_catch
; CHECK: end_try
; CHECK-NOT: global.set __stack_pointer
; CHECK: return
define void @test_no_sp_writeback() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
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) #2 [ "funclet"(token %1) ]
call void @__cxa_end_catch() [ "funclet"(token %1) ]
catchret from %1 to label %try.cont
try.cont: ; preds = %entry, %catch.start
ret void
}
; When the result of @llvm.wasm.get.exception is not used. This is created to
; fix a bug in LateEHPrepare and this should not crash.
define void @test_get_exception_wo_use() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
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)
catchret from %1 to label %try.cont
try.cont: ; preds = %entry, %catch.start
ret void
}
declare void @foo()
declare void @bar(i32*)
declare i32 @__gxx_wasm_personality_v0(...)
declare void @llvm.wasm.throw(i32, i8*)
declare i8* @llvm.wasm.get.exception(token)
declare i32 @llvm.wasm.get.ehselector(token)
declare void @llvm.wasm.rethrow.in.catch()
declare i32 @llvm.eh.typeid.for(i8*)
declare i8* @__cxa_begin_catch(i8*)
declare void @__cxa_end_catch()
declare void @__clang_call_terminate(i8*)
declare %struct.Temp* @_ZN4TempD2Ev(%struct.Temp* returned)
; CHECK: __cpp_exception:
; CHECK: .eventtype __cpp_exception i32
|
