108 lines
2.7 KiB
LLVM
108 lines
2.7 KiB
LLVM
; RUN: opt -S -licm < %s | FileCheck %s
|
|
|
|
; Note: the !invariant.load is there just solely to let us call @use()
|
|
; to add a fake use, and still have the aliasing work out. The call
|
|
; to @use(0) is just to provide a may-unwind exit out of the loop, so
|
|
; that LICM cannot hoist out the load simply because it is guaranteed
|
|
; to execute.
|
|
|
|
declare void @use(i32)
|
|
|
|
define void @f_0(i8* align 4 dereferenceable(1024) %ptr) {
|
|
; CHECK-LABEL: @f_0(
|
|
; CHECK: entry:
|
|
; CHECK: %val = load i32, i32* %ptr.i32
|
|
; CHECK: br label %loop
|
|
; CHECK: loop:
|
|
; CHECK: call void @use(i32 0)
|
|
; CHECK-NEXT: call void @use(i32 %val)
|
|
|
|
|
|
entry:
|
|
%ptr.gep = getelementptr i8, i8* %ptr, i32 32
|
|
%ptr.i32 = bitcast i8* %ptr.gep to i32*
|
|
br label %loop
|
|
|
|
loop:
|
|
call void @use(i32 0)
|
|
%val = load i32, i32* %ptr.i32, !invariant.load !{}
|
|
call void @use(i32 %val)
|
|
br label %loop
|
|
}
|
|
|
|
define void @f_1(i8* align 4 dereferenceable_or_null(1024) %ptr) {
|
|
; CHECK-LABEL: @f_1(
|
|
entry:
|
|
%ptr.gep = getelementptr i8, i8* %ptr, i32 32
|
|
%ptr.i32 = bitcast i8* %ptr.gep to i32*
|
|
%ptr_is_null = icmp eq i8* %ptr, null
|
|
br i1 %ptr_is_null, label %leave, label %loop
|
|
|
|
; CHECK: loop.preheader:
|
|
; CHECK: %val = load i32, i32* %ptr.i32
|
|
; CHECK: br label %loop
|
|
; CHECK: loop:
|
|
; CHECK: call void @use(i32 0)
|
|
; CHECK-NEXT: call void @use(i32 %val)
|
|
|
|
loop:
|
|
call void @use(i32 0)
|
|
%val = load i32, i32* %ptr.i32, !invariant.load !{}
|
|
call void @use(i32 %val)
|
|
br label %loop
|
|
|
|
leave:
|
|
ret void
|
|
}
|
|
|
|
define void @f_2(i8* align 4 dereferenceable_or_null(1024) %ptr) {
|
|
; CHECK-LABEL: @f_2(
|
|
; CHECK-NOT: load
|
|
; CHECK: call void @use(i32 0)
|
|
; CHECK-NEXT: %val = load i32, i32* %ptr.i32, align 4, !invariant.load !0
|
|
; CHECK-NEXT: call void @use(i32 %val)
|
|
|
|
entry:
|
|
;; Can't hoist, since the alignment does not work out -- (<4 byte
|
|
;; aligned> + 30) is not necessarily 4 byte aligned.
|
|
|
|
%ptr.gep = getelementptr i8, i8* %ptr, i32 30
|
|
%ptr.i32 = bitcast i8* %ptr.gep to i32*
|
|
%ptr_is_null = icmp eq i8* %ptr, null
|
|
br i1 %ptr_is_null, label %leave, label %loop
|
|
|
|
loop:
|
|
call void @use(i32 0)
|
|
%val = load i32, i32* %ptr.i32, !invariant.load !{}
|
|
call void @use(i32 %val)
|
|
br label %loop
|
|
|
|
leave:
|
|
ret void
|
|
}
|
|
|
|
define void @checkLaunder(i8* align 4 dereferenceable(1024) %p) {
|
|
; CHECK-LABEL: @checkLaunder(
|
|
; CHECK: entry:
|
|
; CHECK: %l = call i8* @llvm.launder.invariant.group.p0i8(i8* %p)
|
|
; CHECK: %val = load i8, i8* %l
|
|
; CHECK: br label %loop
|
|
; CHECK: loop:
|
|
; CHECK: call void @use(i32 0)
|
|
; CHECK-NEXT: call void @use8(i8 %val)
|
|
|
|
entry:
|
|
%l = call i8* @llvm.launder.invariant.group.p0i8(i8* %p)
|
|
br label %loop
|
|
|
|
loop:
|
|
call void @use(i32 0)
|
|
%val = load i8, i8* %l, !invariant.load !{}
|
|
call void @use8(i8 %val)
|
|
br label %loop
|
|
}
|
|
|
|
declare i8* @llvm.launder.invariant.group.p0i8(i8*)
|
|
|
|
declare void @use8(i8)
|