ARM: simplify and extend byval handling

The main issue being fixed here is that APCS targets handling a "byval align N"
parameter with N > 4 were miscounting what objects were where on the stack,
leading to FrameLowering setting the frame pointer incorrectly and clobbering
the stack.

But byval handling had grown over many years, and had multiple layers of cruft
trying to compensate for each other and calculate padding correctly. This only
really needs to be done once, in the HandleByVal function. Elsewhere should
just do what it's told by that call.

I also stripped out unnecessary APCS/AAPCS distinctions (now that Clang emits
byvals with the correct C ABI alignment), which simplified HandleByVal.

rdar://20095672

llvm-svn: 231959

1 files changed, 28 insertions, 28 deletions

diff --git a/llvm/test/CodeGen/ARM/debug-frame-vararg.ll b/llvm/test/CodeGen/ARM/debug-frame-vararg.ll
index 2608623b986..4ff3fa03d65 100644
--- a/llvm/test/CodeGen/ARM/debug-frame-vararg.ll
+++ b/llvm/test/CodeGen/ARM/debug-frame-vararg.ll
@@ -62,51 +62,51 @@
 
 ; CHECK-FP-LABEL: sum
 ; CHECK-FP: .cfi_startproc
-; CHECK-FP: sub    sp, sp, #16
-; CHECK-FP: .cfi_def_cfa_offset 16
+; CHECK-FP: sub    sp, sp, #12
+; CHECK-FP: .cfi_def_cfa_offset 12
 ; CHECK-FP: push   {r4, lr}
+; CHECK-FP: .cfi_def_cfa_offset 20
+; CHECK-FP: .cfi_offset lr, -16
+; CHECK-FP: .cfi_offset r4, -20
+; CHECK-FP: sub    sp, sp, #4
 ; CHECK-FP: .cfi_def_cfa_offset 24
-; CHECK-FP: .cfi_offset lr, -20
-; CHECK-FP: .cfi_offset r4, -24
-; CHECK-FP: sub    sp, sp, #8
-; CHECK-FP: .cfi_def_cfa_offset 32
 
 ; CHECK-FP-ELIM-LABEL: sum
 ; CHECK-FP-ELIM: .cfi_startproc
-; CHECK-FP-ELIM: sub    sp, sp, #16
-; CHECK-FP-ELIM: .cfi_def_cfa_offset 16
+; CHECK-FP-ELIM: sub    sp, sp, #12
+; CHECK-FP-ELIM: .cfi_def_cfa_offset 12
 ; CHECK-FP-ELIM: push   {r4, r10, r11, lr}
-; CHECK-FP-ELIM: .cfi_def_cfa_offset 32
-; CHECK-FP-ELIM: .cfi_offset lr, -20
-; CHECK-FP-ELIM: .cfi_offset r11, -24
-; CHECK-FP-ELIM: .cfi_offset r10, -28
-; CHECK-FP-ELIM: .cfi_offset r4, -32
+; CHECK-FP-ELIM: .cfi_def_cfa_offset 28
+; CHECK-FP-ELIM: .cfi_offset lr, -16
+; CHECK-FP-ELIM: .cfi_offset r11, -20
+; CHECK-FP-ELIM: .cfi_offset r10, -24
+; CHECK-FP-ELIM: .cfi_offset r4, -28
 ; CHECK-FP-ELIM: add    r11, sp, #8
-; CHECK-FP-ELIM: .cfi_def_cfa r11, 24
+; CHECK-FP-ELIM: .cfi_def_cfa r11, 20
 
 ; CHECK-THUMB-FP-LABEL: sum
 ; CHECK-THUMB-FP: .cfi_startproc
-; CHECK-THUMB-FP: sub    sp, #16
-; CHECK-THUMB-FP: .cfi_def_cfa_offset 16
+; CHECK-THUMB-FP: sub    sp, #12
+; CHECK-THUMB-FP: .cfi_def_cfa_offset 12
 ; CHECK-THUMB-FP: push   {r4, lr}
+; CHECK-THUMB-FP: .cfi_def_cfa_offset 20
+; CHECK-THUMB-FP: .cfi_offset lr, -16
+; CHECK-THUMB-FP: .cfi_offset r4, -20
+; CHECK-THUMB-FP: sub    sp, #4
 ; CHECK-THUMB-FP: .cfi_def_cfa_offset 24
-; CHECK-THUMB-FP: .cfi_offset lr, -20
-; CHECK-THUMB-FP: .cfi_offset r4, -24
-; CHECK-THUMB-FP: sub    sp, #8
-; CHECK-THUMB-FP: .cfi_def_cfa_offset 32
 
 ; CHECK-THUMB-FP-ELIM-LABEL: sum
 ; CHECK-THUMB-FP-ELIM: .cfi_startproc
-; CHECK-THUMB-FP-ELIM: sub    sp, #16
-; CHECK-THUMB-FP-ELIM: .cfi_def_cfa_offset 16
+; CHECK-THUMB-FP-ELIM: sub    sp, #12
+; CHECK-THUMB-FP-ELIM: .cfi_def_cfa_offset 12
 ; CHECK-THUMB-FP-ELIM: push   {r4, r6, r7, lr}
-; CHECK-THUMB-FP-ELIM: .cfi_def_cfa_offset 32
-; CHECK-THUMB-FP-ELIM: .cfi_offset lr, -20
-; CHECK-THUMB-FP-ELIM: .cfi_offset r7, -24
-; CHECK-THUMB-FP-ELIM: .cfi_offset r6, -28
-; CHECK-THUMB-FP-ELIM: .cfi_offset r4, -32
+; CHECK-THUMB-FP-ELIM: .cfi_def_cfa_offset 28
+; CHECK-THUMB-FP-ELIM: .cfi_offset lr, -16
+; CHECK-THUMB-FP-ELIM: .cfi_offset r7, -20
+; CHECK-THUMB-FP-ELIM: .cfi_offset r6, -24
+; CHECK-THUMB-FP-ELIM: .cfi_offset r4, -28
 ; CHECK-THUMB-FP-ELIM: add    r7, sp, #8
-; CHECK-THUMB-FP-ELIM: .cfi_def_cfa r7, 24
+; CHECK-THUMB-FP-ELIM: .cfi_def_cfa r7, 20
 
 define i32 @sum(i32 %count, ...) {
 entry: