| ; 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 ptr 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, ptr @v, align 4 |
| %inc = add nsw i32 %0, 1 |
| store i32 %inc, ptr @v, align 4 |
| %1 = load ptr, ptr @p, align 8 |
| store i32 %n, ptr %1, align 4 |
| %2 = load i32, ptr @v, align 4 |
| %inc1 = add nsw i32 %2, 1 |
| store i32 %inc1, ptr @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, ptr @v, align 4 |
| ; CHECK: store i32 {{.*}}, ptr @v, align 4 |
| ; CHECK-NOT: load i32, ptr @v, align 4 |
| ; CHECK-NOT: store i32 {{.*}}, ptr @v, align 4 |
| |
| ; Same as @bar above, in case the functions are processed in reverse order. |
| define void @bar2() { |
| entry: |
| ret void |
| } |