exceptions.m
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// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fobjc-runtime=macosx-fragile-10.5 -emit-llvm -fobjc-exceptions -mllvm -simplifycfg-sink-common=false -O2 -o - %s | FileCheck %s
//
// <rdar://problem/7471679> [irgen] [eh] Exception code built with clang (x86_64) crashes
// Just check that we don't emit any dead blocks.
@interface NSArray @end
void f0() {
@try {
@try {
@throw @"a";
} @catch(NSArray *e) {
}
} @catch (id e) {
}
}
// CHECK-LABEL: define void @f1()
void f1() {
extern void foo(void);
while (1) {
// CHECK: call void @objc_exception_try_enter
// CHECK-NEXT: getelementptr
// CHECK-NEXT: call i32 @_setjmp(
// CHECK-NEXT: icmp
// CHECK-NEXT: br i1
@try {
// CHECK: call void asm sideeffect "", "=*m"
// CHECK: call void asm sideeffect "", "*m"
// CHECK-NEXT: call void @foo()
foo();
// CHECK: call void @objc_exception_try_exit
} @finally {
break;
}
}
}
// Test that modifications to local variables are respected under
// optimization. rdar://problem/8160285
// CHECK-LABEL: define i32 @f2()
int f2() {
extern void foo(void);
// CHECK: [[X:%.*]] = alloca i32
// CHECK: store i32 5, i32* [[X]]
int x = 0;
x += 5;
// CHECK: [[SETJMP:%.*]] = call i32 @_setjmp
// CHECK-NEXT: [[CAUGHT:%.*]] = icmp eq i32 [[SETJMP]], 0
// CHECK-NEXT: br i1 [[CAUGHT]]
@try {
// Landing pad. Note that we elide the re-enter.
// CHECK: call void asm sideeffect "", "=*m,=*m"(i32* nonnull [[X]]
// CHECK-NEXT: call i8* @objc_exception_extract
// CHECK-NEXT: [[T1:%.*]] = load i32, i32* [[X]]
// CHECK-NEXT: [[T2:%.*]] = add nsw i32 [[T1]], -1
// This store is dead.
// CHECK-NEXT: store i32 [[T2]], i32* [[X]]
// CHECK: store i32 6, i32* [[X]]
x++;
// CHECK-NEXT: call void asm sideeffect "", "*m,*m"(i32* nonnull [[X]]
// CHECK-NEXT: call void @foo()
// CHECK-NEXT: call void @objc_exception_try_exit
// CHECK-NEXT: [[T:%.*]] = load i32, i32* [[X]]
foo();
} @catch (id) {
x--;
}
return x;
}
// Test that the cleanup destination is saved when entering a finally
// block. rdar://problem/8293901
// CHECK-LABEL: define void @f3()
void f3() {
extern void f3_helper(int, int*);
// CHECK: [[X:%.*]] = alloca i32
// CHECK: [[XPTR:%.*]] = bitcast i32* [[X]] to i8*
// CHECK: call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull [[XPTR]])
// CHECK: store i32 0, i32* [[X]]
int x = 0;
// CHECK: call void @objc_exception_try_enter(
// CHECK: call i32 @_setjmp
// CHECK-NEXT: [[DEST1:%.*]] = icmp eq
// CHECK-NEXT: br i1 [[DEST1]]
@try {
// CHECK: call void @f3_helper(i32 0, i32* nonnull [[X]])
// CHECK: call void @objc_exception_try_exit(
f3_helper(0, &x);
} @finally {
// CHECK: call void @objc_exception_try_enter
// CHECK: call i32 @_setjmp
// CHECK-NEXT: [[DEST2:%.*]] = icmp eq
// CHECK-NEXT: br i1 [[DEST2]]
@try {
// CHECK: call void @f3_helper(i32 1, i32* nonnull [[X]])
// CHECK: call void @objc_exception_try_exit(
f3_helper(1, &x);
} @finally {
// CHECK: call void @f3_helper(i32 2, i32* nonnull [[X]])
f3_helper(2, &x);
// This loop is large enough to dissuade the optimizer from just
// duplicating the finally block.
while (x) f3_helper(3, &x);
// This is a switch or maybe some chained branches, but relying
// on a specific result from the optimizer is really unstable.
// CHECK: [[DEST2]]
}
// This is a switch or maybe some chained branches, but relying
// on a specific result from the optimizer is really unstable.
// CHECK: [[DEST1]]
}
// CHECK: call void @f3_helper(i32 4, i32* nonnull [[X]])
// CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull [[XPTR]])
// CHECK-NEXT: ret void
f3_helper(4, &x);
}
// rdar://problem/8440970
void f4() {
extern void f4_help(int);
// CHECK-LABEL: define void @f4()
// CHECK: [[EXNDATA:%.*]] = alloca [[EXNDATA_T:%.*]], align
// CHECK: call void @objc_exception_try_enter([[EXNDATA_T]]* nonnull [[EXNDATA]])
// CHECK: call i32 @_setjmp
@try {
// CHECK: call void @f4_help(i32 0)
f4_help(0);
// The finally cleanup has two threaded entrypoints after optimization:
// finally.no-call-exit: Predecessor is when the catch throws.
// CHECK: call i8* @objc_exception_extract([[EXNDATA_T]]* nonnull [[EXNDATA]])
// CHECK-NEXT: call void @f4_help(i32 2)
// CHECK-NEXT: br label
// -> rethrow
// finally.call-exit: Predecessors are the @try and @catch fallthroughs
// as well as the no-match case in the catch mechanism. The i1 is whether
// to rethrow and should be true only in the last case.
// CHECK: phi i8*
// CHECK-NEXT: phi i1
// CHECK-NEXT: call void @objc_exception_try_exit([[EXNDATA_T]]* nonnull [[EXNDATA]])
// CHECK-NEXT: call void @f4_help(i32 2)
// CHECK-NEXT: br i1
// -> ret, rethrow
// ret:
// CHECK: ret void
// Catch mechanism:
// CHECK: call i8* @objc_exception_extract([[EXNDATA_T]]* nonnull [[EXNDATA]])
// CHECK-NEXT: call void @objc_exception_try_enter([[EXNDATA_T]]* nonnull [[EXNDATA]])
// CHECK: call i32 @_setjmp
// -> next, finally.no-call-exit
// CHECK: call i32 @objc_exception_match
// -> finally.call-exit, match
} @catch (NSArray *a) {
// match:
// CHECK: call void @f4_help(i32 1)
// CHECK-NEXT: br label
// -> finally.call-exit
f4_help(1);
} @finally {
f4_help(2);
}
// rethrow:
// CHECK: phi i8*
// CHECK-NEXT: call void @objc_exception_throw(i8*
// CHECK-NEXT: unreachable
}