1; RUN: llc -mtriple=thumbv7-linux-gnueabi -o - %s | FileCheck %s
2
3; This alloca is just large enough that FrameLowering decides it needs a frame
4; to guarantee access, based on the range of ldrex.
5
6; The actual alloca size is a bit of black magic, unfortunately: the real
7; maximum accessible is 1020, but FrameLowering adds 16 bytes to its estimated
8; stack size just because so the alloca is not actually the what the limit gets
9; compared to. The important point is that we don't go up to ~4096, which is the
10; default with no strange instructions.
11define void @test_large_frame() {
12; CHECK-LABEL: test_large_frame:
13; CHECK: push
14; CHECK: sub.w sp, sp, #1008
15
16  %ptr = alloca i32, i32 252
17
18  %addr = getelementptr i32, i32* %ptr, i32 1
19  call i32 @llvm.arm.ldrex.p0i32(i32* %addr)
20  ret void
21}
22
23; This alloca is just is just the other side of the limit, so no frame
24define void @test_small_frame() {
25; CHECK-LABEL: test_small_frame:
26; CHECK-NOT: push
27; CHECK: sub.w sp, sp, #1004
28
29  %ptr = alloca i32, i32 251
30
31  %addr = getelementptr i32, i32* %ptr, i32 1
32  call i32 @llvm.arm.ldrex.p0i32(i32* %addr)
33  ret void
34}
35
36declare i32 @llvm.arm.ldrex.p0i32(i32*)
37