forked from OSchip/llvm-project
68 lines
2.6 KiB
LLVM
68 lines
2.6 KiB
LLVM
; RUN: opt -O3 -S < %s -enable-new-pm=0 | FileCheck %s
|
|
; RUN: opt -passes='default<O3>' -S < %s | FileCheck %s
|
|
target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"
|
|
target triple = "aarch64"
|
|
|
|
@v = internal unnamed_addr global i32 0, align 4
|
|
@p = common global i32* null, align 8
|
|
|
|
|
|
; This test checks that a number of loads and stores are eliminated,
|
|
; that can only be eliminated based on GlobalsAA information. As such,
|
|
; it tests that GlobalsAA information is retained until the passes
|
|
; that perform this optimization, and it protects against accidentally
|
|
; dropping the GlobalsAA information earlier in the pipeline, which
|
|
; has happened a few times.
|
|
|
|
; GlobalsAA invalidation might happen later in the FunctionPassManager
|
|
; pipeline than the optimization eliminating unnecessary loads/stores.
|
|
; Since GlobalsAA is a module-level analysis, any FunctionPass
|
|
; invalidating the GlobalsAA information will affect FunctionPass
|
|
; pipelines that execute later. For example, assume a FunctionPass1 |
|
|
; FunctionPass2 pipeline and 2 functions to be processed: f1 and f2.
|
|
; Assume furthermore that FunctionPass1 uses GlobalsAA info to do an
|
|
; optimization, and FunctionPass2 invalidates GlobalsAA. Assume the
|
|
; function passes run in the following order: FunctionPass1(f1),
|
|
; FunctionPass2(f1), FunctionPass1(f2), FunctionPass2(f2). Then
|
|
; FunctionPass1 will not be able to optimize f2, since GlobalsAA will
|
|
; have been invalidated in FuntionPass2(f1).
|
|
|
|
; To try and also test this scenario, there is an empty function
|
|
; before and after the function we're checking so that one of them
|
|
; will be processed by the whole set of FunctionPasses before @f. That
|
|
; will ensure that if the invalidation happens, it happens before the
|
|
; actual optimizations on @f start.
|
|
define void @bar() {
|
|
entry:
|
|
ret void
|
|
}
|
|
|
|
; Function Attrs: norecurse nounwind
|
|
define void @f(i32 %n) {
|
|
entry:
|
|
%0 = load i32, i32* @v, align 4
|
|
%inc = add nsw i32 %0, 1
|
|
store i32 %inc, i32* @v, align 4
|
|
%1 = load i32*, i32** @p, align 8
|
|
store i32 %n, i32* %1, align 4
|
|
%2 = load i32, i32* @v, align 4
|
|
%inc1 = add nsw i32 %2, 1
|
|
store i32 %inc1, i32* @v, align 4
|
|
ret void
|
|
}
|
|
|
|
; check variable v is loaded/stored only once after optimization,
|
|
; which should be prove that globalsAA survives until the optimization
|
|
; that can use it to optimize away the duplicate load/stores on
|
|
; variable v.
|
|
; CHECK: load i32, i32* @v, align 4
|
|
; CHECK: store i32 {{.*}}, i32* @v, align 4
|
|
; CHECK-NOT: load i32, i32* @v, align 4
|
|
; CHECK-NOT: store i32 {{.*}}, i32* @v, align 4
|
|
|
|
; Same as @bar above, in case the functions are processed in reverse order.
|
|
define void @bar2() {
|
|
entry:
|
|
ret void
|
|
}
|