llvm-6502/test/CodeGen/WinEH/cppeh-alloca-sink.ll
Reid Kleckner 8f32e5f0d6 Rename llvm.frameescape and llvm.framerecover to localescape and localrecover
Summary:
Initially, these intrinsics seemed like part of a family of "frame"
related intrinsics, but now I think that's more confusing than helpful.
Initially, the LangRef specified that this would create a new kind of
allocation that would be allocated at a fixed offset from the frame
pointer (EBP/RBP). We ended up dropping that design, and leaving the
stack frame layout alone.

These intrinsics are really about sharing local stack allocations, not
frame pointers. I intend to go further and add an `llvm.localaddress()`
intrinsic that returns whatever register (EBP, ESI, ESP, RBX) is being
used to address locals, which should not be confused with the frame
pointer.

Naming suggestions at this point are welcome, I'm happy to re-run sed.

Reviewers: majnemer, nicholas

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11011

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241633 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-07 22:25:32 +00:00

181 lines
6.8 KiB
LLVM

; 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 personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*) {
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 }
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.localescape(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 personality i8* bitcast (i32 (...)* @__CxxFrameHandler3 to i8*) {
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 }
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 }
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.localescape(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.localrecover({{.*}}, 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.localrecover({{.*}}, 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 }