[PATCH] D61970: [CodeGen][ObjC] Call objc_autoreleaseReturnValue and objc_retainAutoreleasedReturnValue instead of objc_autorelease and objc_retain in MRR

[Akira Hatanaka via Phabricator via cfe-commits]

ahatanak added inline comments.


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Comment at: test/CodeGenObjC/convert-messages-to-runtime-calls.m:32
   // CALLS: {{call.*@objc_allocWithZone}}
-  // CALLS: {{call.*@objc_retain}}
+  // CALLS-ARC-INTRINSICS: {{call.*@llvm.objc.retainAutoreleasedReturnValue}}
+  // CALLS-NO-ARC-INTRINSICS: {{call.*@objc_retain}}
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ddkilzer wrote:
> Silly question:  Should `objc_retainAutoreleasedReturnValue` really be called here when the value is not used in a `return` statement?
ARC optimizer has an optimization that converts a call to `objc_retainAutoreleasedReturnValue` to a call to `objc_retain` when it doesn't use the result of a call.

http://llvm.org/doxygen/ObjCARCOpts_8cpp_source.html

Also, it converts a call to `objc_autoreleaseReturnValue` to a call to `objc_autorelease` when its result isn't used by a return instruction.


Repository:
  rC Clang

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  https://reviews.llvm.org/D61970/new/

https://reviews.llvm.org/D61970