From 54ed08e250a76b570c2162d49633e11b8ebb2d98 Mon Sep 17 00:00:00 2001 From: Tim Northover Date: Mon, 9 Dec 2013 09:05:30 +0000 Subject: Merge r196725 (conflicts on same API as before): ------------------------------------------------------------------------ r196725 | tnorthover | 2013-12-08 15:56:50 +0000 (Sun, 08 Dec 2013) | 19 lines ARM: fix folding of stack-adjustment (yet again). When trying to eliminate an "sub sp, sp, #N" instruction by folding it into an existing push/pop using dummy registers, we need to account for the fact that this might affect precisely how "fp" gets set in the prologue. We were attempting this, but assuming that *whenever* we performed a fold it would make a difference. This is false, for example, in: push {r4, r7, lr} add fp, sp, #4 vpush {d8} sub sp, sp, #8 we can fold the "sub" into the "vpush", forming "vpush {d7, d8}". However, in that case the "add fp" instruction mustn't change, which we were getting wrong before. Should fix PR18160. ------------------------------------------------------------------------ git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_34@196769 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/CodeGen/ARM/fold-stack-adjust.ll | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'test') diff --git a/test/CodeGen/ARM/fold-stack-adjust.ll b/test/CodeGen/ARM/fold-stack-adjust.ll index 8c60bca1db..67fd129fd1 100644 --- a/test/CodeGen/ARM/fold-stack-adjust.ll +++ b/test/CodeGen/ARM/fold-stack-adjust.ll @@ -137,6 +137,15 @@ define void @test_fold_point(i1 %tst) minsize { ; CHECK: {{LBB[0-9]+_2}}: ; CHECK-NEXT: vpop {d7, d8} ; CHECK-NEXT: pop {r4, pc} + + ; With a guaranteed frame-pointer, we want to make sure that its offset in the + ; push block is correct, even if a few registers have been tacked onto a later + ; vpush (PR18160). +; CHECK-IOS-LABEL: test_fold_point: +; CHECK-IOS: push {r4, r7, lr} +; CHECK-IOS-NEXT: add r7, sp, #4 +; CHECK-IOS-NEXT: vpush {d7, d8} + ; We want some memory so there's a stack adjustment to fold... %var = alloca i8, i32 8 -- cgit v1.2.3