llvm-6502/test/Transforms/Inline/inline_invoke.ll
John McCall d7c1086201 Implement and document the llvm.eh.resume intrinsic, which is
transformed by the inliner into a branch to the enclosing landing pad
(when inlined through an invoke).  If not so optimized, it is lowered
DWARF EH preparation into a call to _Unwind_Resume (or _Unwind_SjLj_Resume
as appropriate).  Its chief advantage is that it takes both the
exception value and the selector value as arguments, meaning that there
is zero effort in recovering these;  however, the frontend is required
to pass these down, which is not actually particularly difficult.

Also document the behavior of landing pads a bit better, and make it
clearer that it's okay that personality functions don't always land at
landing pads.  This is just a fact of life.  Don't write optimizations that
rely on pushing things over an unwind edge.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132253 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-28 07:45:59 +00:00

108 lines
3.5 KiB
LLVM

; RUN: opt < %s -inline -S | FileCheck %s
; Test that the inliner correctly handles inlining into invoke sites
; by appending selectors and forwarding _Unwind_Resume directly to the
; enclosing landing pad.
%struct.A = type { i8 }
@_ZTIi = external constant i8*
declare void @_ZN1AC1Ev(%struct.A*)
declare void @_ZN1AD1Ev(%struct.A*)
declare i8* @llvm.eh.exception() nounwind readonly
declare i32 @llvm.eh.selector(i8*, i8*, ...) nounwind
declare i32 @llvm.eh.typeid.for(i8*) nounwind
declare void @llvm.eh.resume(i8*, i32)
declare i32 @__gxx_personality_v0(...)
declare i8* @__cxa_begin_catch(i8*)
declare void @__cxa_end_catch()
declare void @_ZSt9terminatev()
define internal void @test0_in() alwaysinline uwtable ssp {
entry:
%a = alloca %struct.A, align 1
%b = alloca %struct.A, align 1
call void @_ZN1AC1Ev(%struct.A* %a)
invoke void @_ZN1AC1Ev(%struct.A* %b)
to label %invoke.cont unwind label %lpad
invoke.cont:
invoke void @_ZN1AD1Ev(%struct.A* %b)
to label %invoke.cont1 unwind label %lpad
invoke.cont1:
call void @_ZN1AD1Ev(%struct.A* %a)
ret void
lpad:
%exn = call i8* @llvm.eh.exception() nounwind
%eh.selector = call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* %exn, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i32 0) nounwind
invoke void @_ZN1AD1Ev(%struct.A* %a)
to label %invoke.cont2 unwind label %terminate.lpad
invoke.cont2:
call void @llvm.eh.resume(i8* %exn, i32 %eh.selector) noreturn
unreachable
terminate.lpad:
%exn3 = call i8* @llvm.eh.exception() nounwind
%eh.selector4 = call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* %exn3, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i8* null) nounwind
call void @_ZSt9terminatev() noreturn nounwind
unreachable
}
define void @test0_out() uwtable ssp {
entry:
invoke void @test0_in()
to label %ret unwind label %lpad
ret:
ret void
lpad: ; preds = %entry
%exn = call i8* @llvm.eh.exception() nounwind
%eh.selector = call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* %exn, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i8* bitcast (i8** @_ZTIi to i8*)) nounwind
%0 = call i32 @llvm.eh.typeid.for(i8* bitcast (i8** @_ZTIi to i8*)) nounwind
%1 = icmp eq i32 %eh.selector, %0
br i1 %1, label %catch, label %eh.resume
catch:
%ignored = call i8* @__cxa_begin_catch(i8* %exn) nounwind
call void @__cxa_end_catch() nounwind
br label %ret
eh.resume:
call void @llvm.eh.resume(i8* %exn, i32 %eh.selector) noreturn
unreachable
}
; CHECK: define void @test0_out()
; CHECK: [[A:%.*]] = alloca %struct.A,
; CHECK: [[B:%.*]] = alloca %struct.A,
; CHECK: invoke void @_ZN1AC1Ev(%struct.A* [[A]])
; CHECK: invoke void @_ZN1AC1Ev(%struct.A* [[B]])
; CHECK: invoke void @_ZN1AD1Ev(%struct.A* [[B]])
; CHECK: invoke void @_ZN1AD1Ev(%struct.A* [[A]])
; CHECK: call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* {{%.*}}, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i32 0, i8* bitcast (i8** @_ZTIi to i8*))
; CHECK-NEXT: invoke void @_ZN1AD1Ev(%struct.A* [[A]])
; CHECK-NEXT: to label %[[LBL:[^\s]+]] unwind
; CHECK: [[LBL]]:
; CHECK-NEXT: br label %[[LPAD:[^\s]+]]
; CHECK: ret void
; CHECK: call i8* @llvm.eh.exception()
; CHECK-NEXT: call i32 (i8*, i8*, ...)* @llvm.eh.selector(i8* {{%.*}}, i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*), i8* bitcast (i8** @_ZTIi to i8*))
; CHECK-NEXT: br label %[[LPAD]]
; CHECK: [[LPAD]]:
; CHECK-NEXT: phi i8* [
; CHECK-NEXT: phi i32 [
; CHECK-NEXT: call i32 @llvm.eh.typeid.for(