llvm/test/CodeGen/X86/catchret-regmask.ll
Reid Kleckner 0e6b04c2c0 [WinEH] Fix funclet return block clobber mask placement
MBB slot index intervals are half open, not closed. getMBBEndIndex()
returns the slot index of the start of the next block in layout order.
Placing a register mask there is incorrect if the successor of the
funclet return is not laid out after the return. Clang generates IR for
catch bodies before generating the following normal code, so we never
noticed this issue until the D frontend authors filed a bug about it.

Instead, we can put the clobber mask on the last instruction of the
funclet return block. We still aren't using a register mask operand on
the CATCHRET instruction because it would cause PEI to spill all CSRs,
including XMM regs, in the prologue.

Fixes PR26679.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262035 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-26 16:53:19 +00:00

74 lines
1.8 KiB
LLVM

; RUN: llc < %s | FileCheck %s
target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc"
declare i32 @__CxxFrameHandler3(...)
declare void @throw() noreturn uwtable
declare i8* @getval()
define i8* @reload_out_of_pad(i8* %arg) #0 personality i32 (...)* @__CxxFrameHandler3 {
assertPassed:
invoke void @throw()
to label %unreachable unwind label %catch.dispatch
catch:
%cp = catchpad within %cs [i8* null, i32 0, i8* null]
catchret from %cp to label %return
; This block *must* appear after the catchret to test the bug.
; FIXME: Make this an MIR test so we can control MBB layout.
unreachable:
unreachable
catch.dispatch:
%cs = catchswitch within none [label %catch] unwind to caller
return:
ret i8* %arg
}
; CHECK-LABEL: reload_out_of_pad: # @reload_out_of_pad
; CHECK: movq %rcx, -[[arg_slot:[0-9]+]](%rbp) # 8-byte Spill
; CHECK: callq throw
; CHECK: ud2
; CHECK: movq -[[arg_slot]](%rbp), %rax # 8-byte Reload
; CHECK: retq
; CHECK: "?catch$3@?0?reload_out_of_pad@4HA":
; CHECK-NOT: Reload
; CHECK: retq
define i8* @spill_in_pad() #0 personality i32 (...)* @__CxxFrameHandler3 {
assertPassed:
invoke void @throw()
to label %unreachable unwind label %catch.dispatch
catch:
%cp = catchpad within %cs [i8* null, i32 0, i8* null]
%val = call i8* @getval() [ "funclet"(token %cp) ]
catchret from %cp to label %return
unreachable:
unreachable
catch.dispatch:
%cs = catchswitch within none [label %catch] unwind to caller
return:
ret i8* %val
}
; CHECK-LABEL: spill_in_pad: # @spill_in_pad
; CHECK: callq throw
; CHECK: ud2
; CHECK: movq -[[val_slot:[0-9]+]](%rbp), %rax # 8-byte Reload
; CHECK: retq
; CHECK: "?catch$3@?0?spill_in_pad@4HA":
; CHECK: callq getval
; CHECK: movq %rax, -[[val_slot]](%rbp) # 8-byte Spill
; CHECK: retq
attributes #0 = { uwtable }