llvm-6502/test/CodeGen/AArch64/arm64-platform-reg.ll
Tim Northover 004d725549 AArch64: add backend option to reserve x18 (platform register)
AAPCS64 says that it's up to the platform to specify whether x18 is
reserved, and a first step on that way is to add a flag controlling
it.

From: Andrew Turner <andrew@fubar.geek.nz>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226664 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 15:43:31 +00:00

28 lines
944 B
LLVM

; RUN: llc -mtriple=arm64-apple-ios -o - %s | FileCheck %s --check-prefix=CHECK-RESERVE-X18
; RUN: llc -mtriple=arm64-freebsd-gnu -aarch64-reserve-x18 -o - %s | FileCheck %s --check-prefix=CHECK-RESERVE-X18
; RUN: llc -mtriple=arm64-linux-gnu -o - %s | FileCheck %s
; x18 is reserved as a platform register on Darwin but not on other
; systems. Create loads of register pressure and make sure this is respected.
; Also, fp must always refer to a valid frame record, even if it's not the one
; of the current function, so it shouldn't be used either.
@var = global [30 x i64] zeroinitializer
define void @keep_live() {
%val = load volatile [30 x i64]* @var
store volatile [30 x i64] %val, [30 x i64]* @var
; CHECK: ldr x18
; CHECK: str x18
; CHECK-RESERVE-X18-NOT: ldr fp
; CHECK-RESERVE-X18-NOT: ldr x18
; CHECK-RESERVE-X18: Spill
; CHECK-RESERVE-X18-NOT: ldr fp
; CHECK-RESERVE-X18-NOT: ldr x18
; CHECK-RESERVE-X18: ret
ret void
}