mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-24 11:42:57 +01:00
63 lines
1.6 KiB
LLVM
63 lines
1.6 KiB
LLVM
; RUN: opt -S -dse < %s | FileCheck %s
|
|
|
|
declare void @f()
|
|
declare noalias i8* @malloc(i32) nounwind
|
|
|
|
define void @test_0() {
|
|
; CHECK-LABEL: @test_0(
|
|
%m = call i8* @malloc(i32 24)
|
|
tail call void @f() [ "unknown"(i8* %m) ]
|
|
; CHECK: store i8 -19, i8* %m
|
|
store i8 -19, i8* %m
|
|
ret void
|
|
}
|
|
|
|
define i8* @test_1() {
|
|
; CHECK-LABEL: @test_1(
|
|
%m = call i8* @malloc(i32 24)
|
|
tail call void @f() [ "unknown"(i8* %m) ]
|
|
store i8 -19, i8* %m
|
|
tail call void @f()
|
|
store i8 101, i8* %m
|
|
|
|
; CHECK: tail call void @f() [ "unknown"(i8* %m) ]
|
|
; CHECK: store i8 -19, i8* %m
|
|
; CHECK: tail call void @f()
|
|
; CHECK: store i8 101, i8* %m
|
|
|
|
ret i8* %m
|
|
}
|
|
|
|
define void @test_2() {
|
|
; Since the deopt operand bundle does not escape %m (see caveat below), it is
|
|
; legal to elide the final store that location.
|
|
|
|
; CHECK-LABEL: @test_2(
|
|
%m = call i8* @malloc(i32 24)
|
|
tail call void @f() [ "deopt"(i8* %m) ]
|
|
store i8 -19, i8* %m
|
|
ret void
|
|
|
|
; CHECK: tail call void @f() [ "deopt"(i8* %m) ]
|
|
; CHECK-NEXT: ret void
|
|
}
|
|
|
|
define i8* @test_3() {
|
|
; Since the deopt operand bundle does not escape %m (see caveat below), @f
|
|
; cannot observe the stores to %m
|
|
|
|
; CHECK-LABEL: @test_3(
|
|
%m = call i8* @malloc(i32 24)
|
|
tail call void @f() [ "deopt"(i8* %m) ]
|
|
store i8 -19, i8* %m
|
|
tail call void @f()
|
|
store i8 101, i8* %m
|
|
ret i8* %m
|
|
}
|
|
|
|
|
|
; Caveat: technically, %m can only escape if the calling function is deoptimized
|
|
; at the call site (i.e. the call returns to the "deopt" continuation). Since
|
|
; the calling function body will be invalidated in that case, the calling
|
|
; function can be optimized under the assumption that %m does not escape.
|