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|
; RUN: opt -mtriple=x86_64-pc-windows-msvc -winehprepare -S -o - < %s | FileCheck %s
; This test describes two difficult cases in sinking allocas into child frames.
; We don't currently do this optimization, but we'll need to tweak these tests
; when we do.
; This test is based on the following code:
;
; // In this case we can sink the alloca from the parent into the catch because
; // the lifetime is limited to the catch.
; extern "C" void may_throw();
; extern "C" void sink_alloca_to_catch() {
; try {
; may_throw();
; } catch (int) {
; volatile int only_used_in_catch = 42;
; }
; }
;
; // In this case we cannot. The variable should live as long as the parent
; // frame lives.
; extern "C" void use_catch_var(int *);
; extern "C" void dont_sink_alloca_to_catch(int n) {
; int live_in_out_catch = 0;
; while (n > 0) {
; try {
; may_throw();
; } catch (int) {
; use_catch_var(&live_in_out_catch);
; }
; n--;
; }
; }
target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc"
declare void @may_throw() #1
declare i32 @__CxxFrameHandler3(...)
declare i32 @llvm.eh.typeid.for(i8*) #2
declare void @llvm.eh.begincatch(i8* nocapture, i8* nocapture) #3
declare void @llvm.eh.endcatch() #3
%rtti.TypeDescriptor2 = type { i8**, i8*, [3 x i8] }
%eh.CatchHandlerType = type { i32, i8* }
$"\01??_R0H@8" = comdat any
@"\01??_7type_info@@6B@" = external constant i8*
@"\01??_R0H@8" = linkonce_odr global %rtti.TypeDescriptor2 { i8** @"\01??_7type_info@@6B@", i8* null, [3 x i8] c".H\00" }, comdat
@llvm.eh.handlertype.H.0 = private unnamed_addr constant %eh.CatchHandlerType { i32 0, i8* bitcast (%rtti.TypeDescriptor2* @"\01??_R0H@8" to i8*) }, section "llvm.metadata"
; Function Attrs: uwtable
define void @sink_alloca_to_catch() #0 {
entry:
%0 = alloca i32
%only_used_in_catch = alloca i32, align 4
invoke void @may_throw()
to label %try.cont unwind label %lpad
lpad: ; preds = %entry
%1 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*)
catch %eh.CatchHandlerType* @llvm.eh.handlertype.H.0
%2 = extractvalue { i8*, i32 } %1, 1
%3 = tail call i32 @llvm.eh.typeid.for(i8* bitcast (%eh.CatchHandlerType* @llvm.eh.handlertype.H.0 to i8*)) #3
%matches = icmp eq i32 %2, %3
br i1 %matches, label %catch, label %eh.resume
catch: ; preds = %lpad
%4 = extractvalue { i8*, i32 } %1, 0
call void @llvm.eh.begincatch(i8* %4, i8* null) #3
store volatile i32 42, i32* %only_used_in_catch, align 4
tail call void @llvm.eh.endcatch() #3
br label %try.cont
try.cont: ; preds = %entry, %catch
ret void
eh.resume: ; preds = %lpad
resume { i8*, i32 } %1
}
; CHECK-LABEL: define void @sink_alloca_to_catch()
; CHECK: call void (...) @llvm.frameescape(i32* %only_used_in_catch)
declare void @use_catch_var(i32*) #1
; Function Attrs: uwtable
define void @dont_sink_alloca_to_catch(i32 %n) #0 {
entry:
%0 = alloca i32
%n.addr = alloca i32, align 4
%live_in_out_catch = alloca i32, align 4
%exn.slot = alloca i8*
%ehselector.slot = alloca i32
store i32 %n, i32* %n.addr, align 4
br label %while.cond
while.cond: ; preds = %try.cont, %entry
%1 = load i32, i32* %n.addr, align 4
%cmp = icmp sgt i32 %1, 0
br i1 %cmp, label %while.body, label %while.end
while.body: ; preds = %while.cond
invoke void @may_throw()
to label %invoke.cont unwind label %lpad
invoke.cont: ; preds = %while.body
br label %try.cont
lpad: ; preds = %while.body
%2 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*)
catch i8* bitcast (%eh.CatchHandlerType* @llvm.eh.handlertype.H.0 to i8*)
%3 = extractvalue { i8*, i32 } %2, 0
store i8* %3, i8** %exn.slot
%4 = extractvalue { i8*, i32 } %2, 1
store i32 %4, i32* %ehselector.slot
br label %catch.dispatch
catch.dispatch: ; preds = %lpad
%sel = load i32, i32* %ehselector.slot
%5 = call i32 @llvm.eh.typeid.for(i8* bitcast (%eh.CatchHandlerType* @llvm.eh.handlertype.H.0 to i8*)) #3
%matches = icmp eq i32 %sel, %5
br i1 %matches, label %catch, label %eh.resume
catch: ; preds = %catch.dispatch
%exn = load i8*, i8** %exn.slot
call void @llvm.eh.begincatch(i8* %exn, i8* null) #3
invoke void @use_catch_var(i32* %live_in_out_catch)
to label %invoke.cont2 unwind label %lpad1
invoke.cont2: ; preds = %catch
call void @llvm.eh.endcatch() #3
br label %try.cont
try.cont: ; preds = %invoke.cont2, %invoke.cont
%6 = load i32, i32* %0
%7 = load i32, i32* %n.addr, align 4
%dec = add nsw i32 %7, -1
store i32 %dec, i32* %n.addr, align 4
br label %while.cond
lpad1: ; preds = %catch
%8 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*)
cleanup
%9 = extractvalue { i8*, i32 } %8, 0
store i8* %9, i8** %exn.slot
%10 = extractvalue { i8*, i32 } %8, 1
store i32 %10, i32* %ehselector.slot
call void @llvm.eh.endcatch() #3
br label %eh.resume
while.end: ; preds = %while.cond
ret void
eh.resume: ; preds = %lpad1, %catch.dispatch
%exn3 = load i8*, i8** %exn.slot
%sel4 = load i32, i32* %ehselector.slot
%lpad.val = insertvalue { i8*, i32 } undef, i8* %exn3, 0
%lpad.val5 = insertvalue { i8*, i32 } %lpad.val, i32 %sel4, 1
resume { i8*, i32 } %lpad.val5
}
; CHECK-LABEL: define void @dont_sink_alloca_to_catch(i32 %n)
; CHECK: call void (...) @llvm.frameescape(i32* %live_in_out_catch)
; CHECK-LABEL: define internal i8* @sink_alloca_to_catch.catch(i8*, i8*)
; CHECK: %only_used_in_catch.i8 = call i8* @llvm.framerecover({{.*}}, i32 0)
; CHECK: %only_used_in_catch = bitcast
; CHECK-LABEL: define internal i8* @dont_sink_alloca_to_catch.catch(i8*, i8*)
; CHECK: %live_in_out_catch.i8 = call i8* @llvm.framerecover({{.*}}, i32 0)
; CHECK: %live_in_out_catch = bitcast
attributes #0 = { uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #2 = { nounwind readnone }
attributes #3 = { nounwind }
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