113 lines
3.5 KiB
LLVM
113 lines
3.5 KiB
LLVM
; RUN: opt < %s -instcombine -S | FileCheck %s
|
|
|
|
@glob = global i32 0
|
|
|
|
declare i8* @llvm.stacksave()
|
|
declare void @llvm.stackrestore(i8*)
|
|
|
|
;; Test that llvm.stackrestore is removed when possible.
|
|
define i32* @test1(i32 %P) {
|
|
%tmp = call i8* @llvm.stacksave( )
|
|
call void @llvm.stackrestore( i8* %tmp ) ;; not restoring anything
|
|
%A = alloca i32, i32 %P
|
|
ret i32* %A
|
|
}
|
|
|
|
; CHECK-LABEL: define i32* @test1(
|
|
; CHECK-NOT: call void @llvm.stackrestore
|
|
; CHECK: ret i32*
|
|
|
|
define void @test2(i8* %X) {
|
|
call void @llvm.stackrestore( i8* %X ) ;; no allocas before return.
|
|
ret void
|
|
}
|
|
|
|
; CHECK-LABEL: define void @test2(
|
|
; CHECK-NOT: call void @llvm.stackrestore
|
|
; CHECK: ret void
|
|
|
|
define void @foo(i32 %size) nounwind {
|
|
entry:
|
|
%tmp118124 = icmp sgt i32 %size, 0 ; <i1> [#uses=1]
|
|
br i1 %tmp118124, label %bb.preheader, label %return
|
|
|
|
bb.preheader: ; preds = %entry
|
|
%tmp25 = add i32 %size, -1 ; <i32> [#uses=1]
|
|
%tmp125 = icmp slt i32 %size, 1 ; <i1> [#uses=1]
|
|
%smax = select i1 %tmp125, i32 1, i32 %size ; <i32> [#uses=1]
|
|
br label %bb
|
|
|
|
bb: ; preds = %bb, %bb.preheader
|
|
%i.0.reg2mem.0 = phi i32 [ 0, %bb.preheader ], [ %indvar.next, %bb ] ; <i32> [#uses=2]
|
|
%tmp = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1]
|
|
%tmp23 = alloca i8, i32 %size ; <i8*> [#uses=2]
|
|
%tmp27 = getelementptr i8, i8* %tmp23, i32 %tmp25 ; <i8*> [#uses=1]
|
|
store i8 0, i8* %tmp27, align 1
|
|
%tmp28 = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1]
|
|
%tmp52 = alloca i8, i32 %size ; <i8*> [#uses=1]
|
|
%tmp53 = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1]
|
|
%tmp77 = alloca i8, i32 %size ; <i8*> [#uses=1]
|
|
%tmp78 = call i8* @llvm.stacksave( ) ; <i8*> [#uses=1]
|
|
%tmp102 = alloca i8, i32 %size ; <i8*> [#uses=1]
|
|
call void @bar( i32 %i.0.reg2mem.0, i8* %tmp23, i8* %tmp52, i8* %tmp77, i8* %tmp102, i32 %size ) nounwind
|
|
call void @llvm.stackrestore( i8* %tmp78 )
|
|
call void @llvm.stackrestore( i8* %tmp53 )
|
|
call void @llvm.stackrestore( i8* %tmp28 )
|
|
call void @llvm.stackrestore( i8* %tmp )
|
|
%indvar.next = add i32 %i.0.reg2mem.0, 1 ; <i32> [#uses=2]
|
|
%exitcond = icmp eq i32 %indvar.next, %smax ; <i1> [#uses=1]
|
|
br i1 %exitcond, label %return, label %bb
|
|
|
|
return: ; preds = %bb, %entry
|
|
ret void
|
|
}
|
|
|
|
; CHECK-LABEL: define void @foo(
|
|
; CHECK: %tmp = call i8* @llvm.stacksave()
|
|
; CHECK: alloca i8
|
|
; CHECK-NOT: stacksave
|
|
; CHECK: call void @bar(
|
|
; CHECK-NEXT: call void @llvm.stackrestore(i8* %tmp)
|
|
; CHECK: ret void
|
|
|
|
declare void @bar(i32, i8*, i8*, i8*, i8*, i32)
|
|
|
|
declare void @inalloca_callee(i32* inalloca)
|
|
|
|
define void @test3(i32 %c) {
|
|
entry:
|
|
br label %loop
|
|
|
|
loop:
|
|
%i = phi i32 [0, %entry], [%i1, %loop]
|
|
%save1 = call i8* @llvm.stacksave()
|
|
%argmem = alloca inalloca i32
|
|
store i32 0, i32* %argmem
|
|
call void @inalloca_callee(i32* inalloca %argmem)
|
|
|
|
; This restore cannot be deleted, the restore below does not make it dead.
|
|
call void @llvm.stackrestore(i8* %save1)
|
|
|
|
; FIXME: We should be able to remove this save/restore pair, but we don't.
|
|
%save2 = call i8* @llvm.stacksave()
|
|
store i32 0, i32* @glob
|
|
call void @llvm.stackrestore(i8* %save2)
|
|
%i1 = add i32 1, %i
|
|
%done = icmp eq i32 %i1, %c
|
|
br i1 %done, label %loop, label %return
|
|
|
|
return:
|
|
ret void
|
|
}
|
|
|
|
; CHECK-LABEL: define void @test3(
|
|
; CHECK: loop:
|
|
; CHECK: %i = phi i32 [ 0, %entry ], [ %i1, %loop ]
|
|
; CHECK: %save1 = call i8* @llvm.stacksave()
|
|
; CHECK: %argmem = alloca inalloca i32
|
|
; CHECK: store i32 0, i32* %argmem
|
|
; CHECK: call void @inalloca_callee(i32* inalloca {{.*}} %argmem)
|
|
; CHECK: call void @llvm.stackrestore(i8* %save1)
|
|
; CHECK: br i1 %done, label %loop, label %return
|
|
; CHECK: ret void
|