llvm-6502/test/CodeGen/X86/win_eh_prepare.ll
Reid Kleckner f77571aeac Add a Windows EH preparation pass that zaps resumes
If the personality is not a recognized MSVC personality function, this
pass delegates to the dwarf EH preparation pass. This chaining supports
people on *-windows-itanium or *-windows-gnu targets.

Currently this recognizes some personalities used by MSVC and turns
resume instructions into traps to avoid link errors.  Even if cleanups
are not used in the source program, LLVM requires the frontend to emit a
code path that resumes unwinding after an exception.  Clang does this,
and we get unreachable resume instructions. PR20300 covers cleaning up
these unreachable calls to resume.

Reviewers: majnemer

Differential Revision: http://reviews.llvm.org/D7216

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227405 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 00:41:44 +00:00

81 lines
2.0 KiB
LLVM

; RUN: opt -S -winehprepare -mtriple x86_64-pc-windows-msvc < %s | FileCheck %s
; FIXME: Add and test outlining here.
declare void @maybe_throw()
@_ZTIi = external constant i8*
@g = external global i32
declare i32 @__C_specific_handler(...)
declare i32 @__gxx_personality_seh0(...)
declare i32 @llvm.eh.typeid.for(i8*) readnone nounwind
define i32 @use_seh() {
entry:
invoke void @maybe_throw()
to label %cont unwind label %lpad
cont:
ret i32 0
lpad:
%ehvals = landingpad { i8*, i32 } personality i32 (...)* @__C_specific_handler
cleanup
catch i8* bitcast (i32 (i8*, i8*)* @filt_g to i8*)
%ehsel = extractvalue { i8*, i32 } %ehvals, 1
%filt_g_sel = call i32 @llvm.eh.typeid.for(i8* bitcast (i32 (i8*, i8*)* @filt_g to i8*))
%matches = icmp eq i32 %ehsel, %filt_g_sel
br i1 %matches, label %ret1, label %eh.resume
ret1:
ret i32 1
eh.resume:
resume { i8*, i32 } %ehvals
}
define internal i32 @filt_g(i8*, i8*) {
%g = load i32* @g
ret i32 %g
}
; CHECK-LABEL: define i32 @use_seh()
; CHECK: invoke void @maybe_throw()
; CHECK-NEXT: to label %cont unwind label %lpad
; CHECK: eh.resume:
; CHECK-NEXT: unreachable
; A MinGW64-ish EH style. It could happen if a binary uses both MSVC CRT and
; mingw CRT and is linked with LTO.
define i32 @use_gcc() {
entry:
invoke void @maybe_throw()
to label %cont unwind label %lpad
cont:
ret i32 0
lpad:
%ehvals = landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_seh0
cleanup
catch i8* bitcast (i8** @_ZTIi to i8*)
%ehsel = extractvalue { i8*, i32 } %ehvals, 1
%filt_g_sel = call i32 @llvm.eh.typeid.for(i8* bitcast (i32 (i8*, i8*)* @filt_g to i8*))
%matches = icmp eq i32 %ehsel, %filt_g_sel
br i1 %matches, label %ret1, label %eh.resume
ret1:
ret i32 1
eh.resume:
resume { i8*, i32 } %ehvals
}
; CHECK-LABEL: define i32 @use_gcc()
; CHECK: invoke void @maybe_throw()
; CHECK-NEXT: to label %cont unwind label %lpad
; CHECK: eh.resume:
; CHECK: call void @_Unwind_Resume(i8* %exn.obj)