llvm-6502/test/Transforms/ObjCARC/weak-copies.ll
Arnold Schwaighofer 3036182e99 BasicAA: Use reachabilty instead of dominance for checking value equality in phi
cycles

This allows the value equality check to work even if we don't have a dominator
tree. Also add some more comments.

I was worried about compile time impacts and did not implement reachability but
used the dominance check in the initial patch. The trade-off was that the
dominator tree was required.
The llvm utility function isPotentiallyReachable cuts off the recursive search
after 32 visits. Testing did not show any compile time regressions showing my
worries unjustfied.

No compile time or performance regressions at O3 -flto -mavx on test-suite +
externals.

Addresses review comments from r198290.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198400 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-03 05:47:03 +00:00

90 lines
4.1 KiB
LLVM

; RUN: opt -S -basicaa -objc-arc < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-darwin11.0.0"
%0 = type { i64, i64, i8*, i8*, i8*, i8* }
%1 = type <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i8* }>
%struct.__block_descriptor = type { i64, i64 }
@_NSConcreteStackBlock = external global i8*
@.str = private unnamed_addr constant [6 x i8] c"v8@?0\00"
@"\01L_OBJC_CLASS_NAME_" = internal global [3 x i8] c"\01@\00", section "__TEXT,__objc_classname,cstring_literals", align 1
@__block_descriptor_tmp = internal constant %0 { i64 0, i64 40, i8* bitcast (void (i8*, i8*)* @__copy_helper_block_ to i8*), i8* bitcast (void (i8*)* @__destroy_helper_block_ to i8*), i8* getelementptr inbounds ([6 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([3 x i8]* @"\01L_OBJC_CLASS_NAME_", i32 0, i32 0) }
@"\01L_OBJC_IMAGE_INFO" = internal constant [2 x i32] [i32 0, i32 16], section "__DATA, __objc_imageinfo, regular, no_dead_strip"
@llvm.used = appending global [2 x i8*] [i8* getelementptr inbounds ([3 x i8]* @"\01L_OBJC_CLASS_NAME_", i32 0, i32 0), i8* bitcast ([2 x i32]* @"\01L_OBJC_IMAGE_INFO" to i8*)], section "llvm.metadata"
; Eliminate unnecessary weak pointer copies.
; CHECK: define void @foo() {
; CHECK-NEXT: entry:
; CHECK-NEXT: %call = call i8* @bar()
; CHECK-NEXT: call void @use(i8* %call) [[NUW:#[0-9]+]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @foo() {
entry:
%w = alloca i8*, align 8
%x = alloca i8*, align 8
%call = call i8* @bar()
%0 = call i8* @objc_initWeak(i8** %w, i8* %call) nounwind
%1 = call i8* @objc_loadWeak(i8** %w) nounwind
%2 = call i8* @objc_initWeak(i8** %x, i8* %1) nounwind
%3 = call i8* @objc_loadWeak(i8** %x) nounwind
call void @use(i8* %3) nounwind
call void @objc_destroyWeak(i8** %x) nounwind
call void @objc_destroyWeak(i8** %w) nounwind
ret void
}
; Eliminate unnecessary weak pointer copies in a block initialization.
; CHECK: define void @qux(i8* %me) #0 {
; CHECK-NEXT: entry:
; CHECK-NEXT: %block = alloca %1, align 8
; CHECK-NOT: alloca
; CHECK: }
define void @qux(i8* %me) nounwind {
entry:
%w = alloca i8*, align 8
%block = alloca %1, align 8
%0 = call i8* @objc_retain(i8* %me) nounwind
%1 = call i8* @objc_initWeak(i8** %w, i8* %0) nounwind
%block.isa = getelementptr inbounds %1* %block, i64 0, i32 0
store i8* bitcast (i8** @_NSConcreteStackBlock to i8*), i8** %block.isa, align 8
%block.flags = getelementptr inbounds %1* %block, i64 0, i32 1
store i32 1107296256, i32* %block.flags, align 8
%block.reserved = getelementptr inbounds %1* %block, i64 0, i32 2
store i32 0, i32* %block.reserved, align 4
%block.invoke = getelementptr inbounds %1* %block, i64 0, i32 3
store i8* bitcast (void (i8*)* @__qux_block_invoke_0 to i8*), i8** %block.invoke, align 8
%block.descriptor = getelementptr inbounds %1* %block, i64 0, i32 4
store %struct.__block_descriptor* bitcast (%0* @__block_descriptor_tmp to %struct.__block_descriptor*), %struct.__block_descriptor** %block.descriptor, align 8
%block.captured = getelementptr inbounds %1* %block, i64 0, i32 5
%2 = call i8* @objc_loadWeak(i8** %w) nounwind
%3 = call i8* @objc_initWeak(i8** %block.captured, i8* %2) nounwind
%4 = bitcast %1* %block to void ()*
call void @use_block(void ()* %4) nounwind
call void @objc_destroyWeak(i8** %block.captured) nounwind
call void @objc_destroyWeak(i8** %w) nounwind
call void @objc_release(i8* %0) nounwind, !clang.imprecise_release !0
ret void
}
declare i8* @objc_retain(i8*)
declare void @use_block(void ()*) nounwind
declare void @__qux_block_invoke_0(i8* %.block_descriptor) nounwind
declare void @__copy_helper_block_(i8*, i8*) nounwind
declare void @objc_copyWeak(i8**, i8**)
declare void @__destroy_helper_block_(i8*) nounwind
declare void @objc_release(i8*)
declare i8* @bar()
declare i8* @objc_initWeak(i8**, i8*)
declare i8* @objc_loadWeak(i8**)
declare void @use(i8*) nounwind
declare void @objc_destroyWeak(i8**)
; CHECK: attributes [[NUW]] = { nounwind }
!0 = metadata !{}