[llvm] Reserve R9 on armv6 iOS before 3.0 (PR #150835)

[Jon Roelofs via llvm-commits]

================
@@ -6,12 +6,21 @@
 ; RUN: llc <%s -mtriple=arm-none-eabi --frame-pointer=all 2>&1 \
 ; RUN:   | FileCheck %s -check-prefix=NO_FP_ELIM
 
+; RUN: llc <%s -mtriple=armv6k-apple-ios2 2>&1 | FileCheck %s -check-prefix=IOS2
+
+; RUN: llc <%s -mtriple=armv6k-apple-ios3 2>&1 | FileCheck %s -check-prefix=IOS3
+
+; RUN: llc <%s -mtriple=armv7-apple-ios2 2>&1 | FileCheck %s -check-prefix=IOSV7
+
----------------
jroelofs wrote:

style nit: RUN lines should be contiguous

```suggestion
; RUN: llc <%s -mtriple=armv6k-apple-ios2 2>&1 | FileCheck %s -check-prefix=IOS2
; RUN: llc <%s -mtriple=armv6k-apple-ios3 2>&1 | FileCheck %s -check-prefix=IOS3
; RUN: llc <%s -mtriple=armv7-apple-ios2 2>&1 | FileCheck %s -check-prefix=IOSV7

```

https://github.com/llvm/llvm-project/pull/150835