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|
; RUN: opt < %s -wasm-lower-em-ehsjlj -enable-emscripten-cxx-exceptions -enable-emscripten-sjlj -S | FileCheck %s
; RUN: llc < %s -enable-emscripten-cxx-exceptions -enable-emscripten-sjlj -verify-machineinstrs
; Tests for cases when exception handling and setjmp/longjmp handling are mixed.
target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
target triple = "wasm32-unknown-unknown"
%struct.__jmp_buf_tag = type { [6 x i32], i32, [32 x i32] }
@_ZTIi = external constant i8*
; There is a function call (@foo) that can either throw an exception or longjmp
; and there is also a setjmp call. When @foo throws, we have to check both for
; exception and longjmp and jump to exception or longjmp handling BB depending
; on the result.
define void @setjmp_longjmp_exception() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
; CHECK-LABEL: @setjmp_longjmp_exception
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
invoke void @foo()
to label %try.cont unwind label %lpad
; CHECK: entry.split.split:
; CHECK: %[[CMP0:.*]] = icmp ne i32 %__THREW__.val, 0
; CHECK-NEXT: %__threwValue.val = load i32, i32* @__threwValue
; CHECK-NEXT: %[[CMP1:.*]] = icmp ne i32 %__threwValue.val, 0
; CHECK-NEXT: %[[CMP:.*]] = and i1 %[[CMP0]], %[[CMP1]]
; CHECK-NEXT: br i1 %[[CMP]], label %if.then1, label %if.else1
; This is exception checking part. %if.else1 leads here
; CHECK: entry.split.split.split:
; CHECK-NEXT: %[[CMP:.*]] = icmp eq i32 %__THREW__.val, 1
; CHECK-NEXT: br i1 %[[CMP]], label %lpad, label %try.cont
; CHECK: lpad:
lpad: ; preds = %entry
%0 = landingpad { i8*, i32 }
catch i8* null
%1 = extractvalue { i8*, i32 } %0, 0
%2 = extractvalue { i8*, i32 } %0, 1
; CHECK-NOT: call {{.*}} void @__invoke_void(void ()* @__cxa_end_catch)
%3 = call i8* @__cxa_begin_catch(i8* %1) #2
call void @__cxa_end_catch()
br label %try.cont
try.cont: ; preds = %lpad, %entry
ret void
; longjmp checking part
; CHECK: if.then1:
; CHECK: call i32 @testSetjmp
}
; @foo can either throw an exception or longjmp. Because this function doesn't
; have any setjmp calls, we only handle exceptions in this function. But because
; sjlj is enabled, we check if the thrown value is longjmp and if so rethrow it
; by calling @emscripten_longjmp.
define void @rethrow_longjmp() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
; CHECK-LABEL: @rethrow_longjmp
entry:
invoke void @foo()
to label %try.cont unwind label %lpad
; CHECK: entry:
; CHECK: %cmp.eq.one = icmp eq i32 %__THREW__.val, 1
; CHECK-NEXT: %cmp.eq.zero = icmp eq i32 %__THREW__.val, 0
; CHECK-NEXT: %or = or i1 %cmp.eq.zero, %cmp.eq.one
; CHECK-NEXT: br i1 %or, label %tail, label %rethrow.longjmp
; CHECK: try.cont:
; CHECK-NEXT: %phi = phi i32 [ undef, %tail ], [ undef, %lpad ]
; CHECK-NEXT: ret void
; CHECK: rethrow.longjmp:
; CHECK-NEXT: %threw.phi = phi i32 [ %__THREW__.val, %entry ]
; CHECK-NEXT: %__threwValue.val = load i32, i32* @__threwValue, align 4
; CHECK-NEXT: call void @emscripten_longjmp(i32 %threw.phi, i32 %__threwValue.val
; CHECK-NEXT: unreachable
; CHECK: tail:
; CHECK-NEXT: %cmp = icmp eq i32 %__THREW__.val, 1
; CHECK-NEXT: br i1 %cmp, label %lpad, label %try.cont
lpad: ; preds = %entry
%0 = landingpad { i8*, i32 }
catch i8* null
%1 = extractvalue { i8*, i32 } %0, 0
%2 = extractvalue { i8*, i32 } %0, 1
%3 = call i8* @__cxa_begin_catch(i8* %1) #5
call void @__cxa_end_catch()
br label %try.cont
try.cont: ; preds = %lpad, %entry
%phi = phi i32 [ undef, %entry ], [ undef, %lpad ]
ret void
}
; This function contains a setjmp call and no invoke, so we only handle longjmp
; here. But @foo can also throw an exception, so we check if an exception is
; thrown and if so rethrow it by calling @__resumeException. Also we have to
; free the setjmpTable buffer before calling @__resumeException.
define void @rethrow_exception() {
; CHECK-LABEL: @rethrow_exception
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
%cmp = icmp ne i32 %call, 0
br i1 %cmp, label %return, label %if.end
if.end: ; preds = %entry
call void @foo()
br label %return
; CHECK: if.end:
; CHECK: %cmp.eq.one = icmp eq i32 %__THREW__.val, 1
; CHECK-NEXT: br i1 %cmp.eq.one, label %rethrow.exn, label %normal
; CHECK: rethrow.exn:
; CHECK-NEXT: %exn = call i8* @__cxa_find_matching_catch_2()
; CHECK-NEXT: %[[BUF:.*]] = bitcast i32* %setjmpTable{{.*}} to i8*
; CHECK-NEXT: call void @free(i8* %[[BUF]])
; CHECK-NEXT: call void @__resumeException(i8* %exn)
; CHECK-NEXT: unreachable
; CHECK: normal:
; CHECK-NEXT: icmp ne i32 %__THREW__.val, 0
return: ; preds = %if.end, %entry
ret void
}
; The same as 'rethrow_exception' but contains a __cxa_throw call. We have to
; free the setjmpTable buffer before calling __cxa_throw.
define void @rethrow_exception2() {
; CHECK-LABEL: @rethrow_exception2
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
%cmp = icmp ne i32 %call, 0
br i1 %cmp, label %throw, label %if.end
if.end: ; preds = %entry
call void @foo()
br label %throw
throw: ; preds = %if.end, %entry
call void @__cxa_throw(i8* null, i8* null, i8* null) #1
unreachable
; CHECK: throw:
; CHECK: %[[BUF:.*]] = bitcast i32* %setjmpTable{{.*}} to i8*
; CHECK-NEXT: call void @free(i8* %[[BUF]])
; CHECK-NEXT: call void @__cxa_throw(i8* null, i8* null, i8* null)
; CHECK-NEXT: unreachable
}
; The same case with @rethrow_longjmp, but there are multiple function calls
; that can possibly longjmp (instead of throwing exception) so we have to
; rethrow them. Here we test if we correclty generate only one 'rethrow.longjmp'
; BB and share it for multiple calls.
define void @rethrow_longjmp_multi() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
; CHECK-LABEL: @rethrow_longjmp_multi
entry:
invoke void @foo()
to label %bb unwind label %lpad
bb: ; preds = %entry
invoke void @foo()
to label %try.cont unwind label %lpad
lpad: ; preds = %bb, %entry
%0 = landingpad { i8*, i32 }
catch i8* null
%1 = extractvalue { i8*, i32 } %0, 0
%2 = extractvalue { i8*, i32 } %0, 1
%3 = call i8* @__cxa_begin_catch(i8* %1) #5
call void @__cxa_end_catch()
br label %try.cont
try.cont: ; preds = %lpad, %bb
%phi = phi i32 [ undef, %bb ], [ undef, %lpad ]
ret void
; CHECK: rethrow.longjmp:
; CHECK-NEXT: %threw.phi = phi i32 [ %__THREW__.val, %entry ], [ %__THREW__.val1, %bb ]
; CHECK-NEXT: %__threwValue.val = load i32, i32* @__threwValue, align 4
; CHECK-NEXT: call void @emscripten_longjmp(i32 %threw.phi, i32 %__threwValue.val)
; CHECK-NEXT: unreachable
}
; The same case with @rethrow_exception, but there are multiple function calls
; that can possibly throw (instead of longjmping) so we have to rethrow them.
; Here we test if correctly we generate only one 'rethrow.exn' BB and share it
; for multiple calls.
define void @rethrow_exception_multi() {
; CHECK-LABEL: @rethrow_exception_multi
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
%cmp = icmp ne i32 %call, 0
br i1 %cmp, label %return, label %if.end
if.end: ; preds = %entry
call void @foo()
call void @foo()
br label %return
return: ; preds = %entry, %if.end
ret void
; CHECK: rethrow.exn:
; CHECK-NEXT: %setjmpTable{{.*}} = phi i32* [ %setjmpTable{{.*}}, %if.end.split ], [ %setjmpTable{{.*}}, %if.end ]
; CHECK-NEXT: %exn = call i8* @__cxa_find_matching_catch_2()
; CHECK-NEXT: %{{.*}} = bitcast i32* %setjmpTable{{.*}} to i8*
; CHECK-NEXT: tail call void @free(i8* %{{.*}})
; CHECK-NEXT: call void @__resumeException(i8* %exn)
; CHECK-NEXT: unreachable
}
; int jmpval = setjmp(buf);
; if (jmpval != 0)
; return;
; try {
; throw 3;
; } catch (...) {
; }
define void @setjmp_with_throw_try_catch() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
; CHECK-LABEL: @setjmp_with_throw_try_catch
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
%cmp = icmp ne i32 %call, 0
br i1 %cmp, label %try.cont, label %if.end
if.end: ; preds = %entry
%exception = call i8* @__cxa_allocate_exception(i32 4) #2
%0 = bitcast i8* %exception to i32*
store i32 3, i32* %0, align 16
invoke void @__cxa_throw(i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) #1
to label %unreachable unwind label %lpad
; When invoke @__cxa_throw is converted to a call to the invoke wrapper,
; "noreturn" attribute should be removed, and there should be no 'free' call
; before the call. We insert a 'free' call that frees 'setjmpTable' before every
; function-exiting instruction. And invoke wrapper calls shouldn't be treated as
; noreturn instructions, because they are supposed to return.
; CHECK: if.end:
; CHECK-NOT: tail call void @free
; CHECK-NOT: call cc99 void @"__invoke_void_i8*_i8*_i8*"(void (i8*, i8*, i8*)* @__cxa_throw, i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null) #
; CHECK: call cc99 void @"__invoke_void_i8*_i8*_i8*"(void (i8*, i8*, i8*)* @__cxa_throw, i8* %exception, i8* bitcast (i8** @_ZTIi to i8*), i8* null)
lpad: ; preds = %if.end
%1 = landingpad { i8*, i32 }
catch i8* null
%2 = extractvalue { i8*, i32 } %1, 0
%3 = extractvalue { i8*, i32 } %1, 1
%4 = call i8* @__cxa_begin_catch(i8* %2) #2
call void @__cxa_end_catch()
br label %try.cont
try.cont: ; preds = %entry, %lpad
ret void
unreachable: ; preds = %if.end
unreachable
}
declare void @foo()
; Function Attrs: returns_twice
declare i32 @setjmp(%struct.__jmp_buf_tag*)
; Function Attrs: noreturn
declare void @longjmp(%struct.__jmp_buf_tag*, i32)
declare i32 @__gxx_personality_v0(...)
declare i8* @__cxa_begin_catch(i8*)
declare void @__cxa_end_catch()
declare void @__cxa_throw(i8*, i8*, i8*)
declare i8* @__cxa_allocate_exception(i32)
attributes #0 = { returns_twice }
attributes #1 = { noreturn }
attributes #2 = { nounwind }
|
