hanchenye-llvm-project/clang
Alexander Potapenko 1b5e38a6c9 [CodeGen]: don't treat structures returned in registers as memory inputs
Summary:
The "=r" output constraint for a structure variable passed to inline asm
shouldn't be converted to "=*r", as this changes the asm directive
semantics and prevents DSE optimizations.
Instead, preserve the constraints and return such structures as integers
of corresponding size, which are converted back to structures when
storing the result.

Fixes PR42672.

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65234

llvm-svn: 370335
2019-08-29 11:21:41 +00:00
..
INPUTS
bindings [clang][Tooling] Infer target and mode from argv[0] when using JSONCompilationDatabase 2019-06-26 07:39:03 +00:00
cmake [CMake][Fuchsia] Define asan+noexcept multilib 2019-07-13 08:07:10 +00:00
docs [ReleaseNotes] MemorySanitizer support of ASLR on FreeBSD 2019-08-27 10:04:03 +00:00
examples Fixup build of clang-interpreter example after change in r370122. 2019-08-28 02:13:24 +00:00
include Removed dead code from clang/AST/NSAPI.h 2019-08-29 06:30:12 +00:00
lib [CodeGen]: don't treat structures returned in registers as memory inputs 2019-08-29 11:21:41 +00:00
runtime [GWP-ASan] Mutex implementation [2]. 2019-05-30 19:45:32 +00:00
test [CodeGen]: don't treat structures returned in registers as memory inputs 2019-08-29 11:21:41 +00:00
tools [Clang][Bundler] Do not require host triple for extracting device bundles 2019-08-28 01:26:13 +00:00
unittests ArrayRef'ized CompilerInvocation::CreateFromArgs 2019-08-27 22:13:31 +00:00
utils [OpenCL] Microoptimize OCL2Qual a bit 2019-08-24 13:04:34 +00:00
www Testing commit access; NFC 2019-08-27 12:36:25 +00:00
.arcconfig
.clang-format
.clang-tidy
.gitignore
CMakeLists.txt [CMake] Don't set Python_ADDITIONAL_VERSIONS 2019-07-18 15:17:42 +00:00
CODE_OWNERS.TXT
INSTALL.txt
LICENSE.TXT
ModuleInfo.txt
NOTES.txt
README.txt [NFC] Test commit 2019-06-12 07:50:48 +00:00

README.txt

//===----------------------------------------------------------------------===//
// C Language Family Front-end
//===----------------------------------------------------------------------===//

Welcome to Clang.  This is a compiler front-end for the C family of languages
(C, C++, Objective-C, and Objective-C++) which is built as part of the LLVM
compiler infrastructure project.

Unlike many other compiler frontends, Clang is useful for a number of things
beyond just compiling code: we intend for Clang to be host to a number of
different source-level tools.  One example of this is the Clang Static Analyzer.

If you're interested in more (including how to build Clang) it is best to read
the relevant web sites.  Here are some pointers:

Information on Clang:             http://clang.llvm.org/
Building and using Clang:         http://clang.llvm.org/get_started.html
Clang Static Analyzer:            http://clang-analyzer.llvm.org/
Information on the LLVM project:  http://llvm.org/

If you have questions or comments about Clang, a great place to discuss them is
on the Clang development mailing list:
  http://lists.llvm.org/mailman/listinfo/cfe-dev

If you find a bug in Clang, please file it in the LLVM bug tracker:
  http://llvm.org/bugs/