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; RUN: llc %s --mtriple=x86_64-pc-windows-msvc -o - | FileCheck %s
; Tests the fixed object layouts when two catchpads re-use the same stack
; allocation for this catch objects.
; Generated from this C++ code, with modifications to the IR (see comments in
; IR):
; https://godbolt.org/z/9qv5Yn68j
; > clang --target=x86_64-pc-windows-msvc test.cpp
; ```
; extern "C" void boom();
; extern "C" int calls_boom();
; {
; try { boom(); }
; catch (int& i) { return i; }
; catch (long& l) { return l; }
; return 0;
; }
; ```
; Minimum stack alloc is 64 bytes, so no change there.
; CHECK-LABEL: calls_boom:
; CHECK: subq $64, %rsp
; CHECK: .seh_stackalloc 64
; Both the catch blocks load from the same address.
; CHECK-LABEL: "?catch$3@?0?calls_boom@4HA":
; CHECK: movq -8(%rbp), %rax
; CHECK-LABEL: "?catch$4@?0?calls_boom@4HA":
; CHECK: movq -8(%rbp), %rax
; There's enough space for the UnwindHelp to be at 48 instead of 40
; CHECK-LABEL: $cppxdata$calls_boom:
; CHECK: .long 48 # UnwindHelp
; Both catches have the same object offset.
; CHECK-LABEL: $handlerMap$0$calls_boom:
; CHECK: .long 56 # CatchObjOffset
; CHECK-NEXT: .long "?catch$3@?0?calls_boom@4HA"@IMGREL # Handler
; CHECK: .long 56 # CatchObjOffset
; CHECK-NEXT: .long "?catch$4@?0?calls_boom@4HA"@IMGREL # Handler
%rtti.TypeDescriptor2 = type { ptr, ptr, [3 x i8] }
$"??_R0H@8" = comdat any
$"??_R0J@8" = comdat any
@"??_7type_info@@6B@" = external constant ptr
@"??_R0H@8" = linkonce_odr global %rtti.TypeDescriptor2 { ptr @"??_7type_info@@6B@", ptr null, [3 x i8] c".H\00" }, comdat
@"??_R0J@8" = linkonce_odr global %rtti.TypeDescriptor2 { ptr @"??_7type_info@@6B@", ptr null, [3 x i8] c".J\00" }, comdat
define dso_local i32 @calls_boom() personality ptr @__CxxFrameHandler3 {
entry:
%retval = alloca i32, align 4
; MODIFICATION: Remove unusued alloca
; %l = alloca ptr, align 8
%i = alloca ptr, align 8
invoke void @boom()
to label %invoke.cont unwind label %catch.dispatch
catch.dispatch:
%0 = catchswitch within none [label %catch1, label %catch] unwind to caller
catch1:
%1 = catchpad within %0 [ptr @"??_R0H@8", i32 8, ptr %i]
%2 = load ptr, ptr %i, align 8
%3 = load i32, ptr %2, align 4
store i32 %3, ptr %retval, align 4
catchret from %1 to label %catchret.dest2
catch:
; MODIFICATION: Use %i instead of %l
%4 = catchpad within %0 [ptr @"??_R0J@8", i32 8, ptr %i]
%5 = load ptr, ptr %i, align 8
%6 = load i32, ptr %5, align 4
store i32 %6, ptr %retval, align 4
catchret from %4 to label %catchret.dest
invoke.cont:
br label %try.cont
catchret.dest:
br label %return
catchret.dest2:
br label %return
try.cont:
store i32 0, ptr %retval, align 4
br label %return
return:
%7 = load i32, ptr %retval, align 4
ret i32 %7
}
declare dso_local void @boom() #1
declare dso_local i32 @__CxxFrameHandler3(...)
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