mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-21 18:29:46 +00:00
ARM specific optimiztion, finding places in ARM machine code where 2 dmbs follow one another, and eliminating one of them. Patch by Reinoud Elhorst. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205409 91177308-0d34-0410-b5e6-96231b3b80d8
75 lines
1.6 KiB
LLVM
75 lines
1.6 KiB
LLVM
; RUN: llc < %s -mtriple=armv7 -mattr=+db | FileCheck %s
|
|
|
|
@x1 = global i32 0, align 4
|
|
@x2 = global i32 0, align 4
|
|
|
|
define void @test() {
|
|
entry:
|
|
br label %for.body
|
|
|
|
for.body: ; preds = %for.body, %entry
|
|
%i.013 = phi i32 [ 1, %entry ], [ %inc6, %for.body ]
|
|
store atomic i32 %i.013, i32* @x1 seq_cst, align 4
|
|
store atomic i32 %i.013, i32* @x1 seq_cst, align 4
|
|
store atomic i32 %i.013, i32* @x2 seq_cst, align 4
|
|
%inc6 = add nsw i32 %i.013, 1
|
|
%exitcond = icmp eq i32 %inc6, 2
|
|
br i1 %exitcond, label %for.end, label %for.body
|
|
|
|
for.end: ; preds = %for.body
|
|
ret void
|
|
|
|
; The for.body contains 3 seq_cst stores.
|
|
; Hence it should have 3 dmb;str;dmb sequences with the middle dmbs collapsed
|
|
; CHECK: %for.body
|
|
; CHECK-NOT: str
|
|
; CHECK: dmb
|
|
; CHECK-NOT: dmb
|
|
; CHECK: str
|
|
|
|
; CHECK-NOT: str
|
|
; CHECK: dmb
|
|
; CHECK-NOT: dmb
|
|
; CHECK: str
|
|
|
|
; CHECK-NOT: str
|
|
; CHECK: dmb
|
|
; CHECK-NOT: dmb
|
|
; CHECK: str
|
|
|
|
; CHECK-NOT: str
|
|
; CHECK: dmb
|
|
; CHECK-NOT: dmb
|
|
; CHECK-NOT: str
|
|
; CHECK: %for.end
|
|
}
|
|
|
|
define void @test2() {
|
|
call void @llvm.arm.dmb(i32 11)
|
|
tail call void @test()
|
|
call void @llvm.arm.dmb(i32 11)
|
|
ret void
|
|
; the call should prevent the two dmbs from collapsing
|
|
; CHECK: test2:
|
|
; CHECK: dmb
|
|
; CHECK-NEXT: bl
|
|
; CHECK-NEXT: dmb
|
|
}
|
|
|
|
define void @test3() {
|
|
call void @llvm.arm.dmb(i32 11)
|
|
call void @llvm.arm.dsb(i32 9)
|
|
call void @llvm.arm.dmb(i32 11)
|
|
ret void
|
|
; the call should prevent the two dmbs from collapsing
|
|
; CHECK: test3:
|
|
; CHECK: dmb
|
|
; CHECK-NEXT: dsb
|
|
; CHECK-NEXT: dmb
|
|
|
|
}
|
|
|
|
|
|
declare void @llvm.arm.dmb(i32)
|
|
declare void @llvm.arm.dsb(i32)
|