Commit Graph

8 Commits

Author SHA1 Message Date
Sean Fertile d900dd0c23 Revert "[CodeGenCXX] Treat 'this' as noalias in constructors"
This reverts commit https://reviews.llvm.org/rL344150 which causes
MachineOutliner related failures on the ppc64le multistage buildbot.

llvm-svn: 344526
2018-10-15 15:43:00 +00:00
Anton Bikineev cc7e74753a [CodeGenCXX] Treat 'this' as noalias in constructors
This is currently a clang extension and a resolution
of the defect report in the C++ Standard.

Differential Revision: https://reviews.llvm.org/D46441

llvm-svn: 344150
2018-10-10 16:14:51 +00:00
Derek Schuff 8179be4897 Introduce CGCXXABI::canCallMismatchedFunctionType
llvm-svn: 269089
2016-05-10 17:44:55 +00:00
Derek Schuff cc42df4a30 Do not register incompatible C++ destructors with __cxa_atexit
Summary:
For a static object with a nontrivial destructor, clang generates an
initializer function (__cxx_global_var_init) which registers that
object's destructor using __cxa_atexit. However some ABIs (ARM,
WebAssembly) use destructors that return 'this' instead of having void
return (which does not match the signature of function pointers passed
to __cxa_atexit). This results in undefined behavior when the destructors are
called. All the calling conventions I know of on ARM can tolerate this,
but WebAssembly requires the signatures of indirect calls to match the
called function.

This patch disables that direct registration of destructors for ABIs
that have this-returning destructors.

Subscribers: aemerson, jfb, cfe-commits, dschuff

Differential Revision: http://reviews.llvm.org/D19275

llvm-svn: 269085
2016-05-10 17:44:46 +00:00
Eric Christopher 0e2618857c Have the driver and the target code agree on what the default ABI
is for each machine. Fix up darwin tests that were testing for
aapcs on armv7-ios when the actual ABI is apcs.

Should be no user visible change without -cc1.

llvm-svn: 223429
2014-12-05 01:06:59 +00:00
Nico Weber bdc969839a Include translation unit filename in global ctor symbol names.
This makes it easier to see where a global ctor comes from, and it also makes
ASan's init order analyzer output easier to understand.  gcc does this too,
but only in -fPIC mode for some reason.  Don't do this for constructors with
explicit init priority.

Also prepend "sub_" before the 'I', that way regular constructors stay
lexicographically after symbols with init priority (because
ord('s') > ord('I')).  gold seems to ignore the name of constructor symbols,
and ld only looks at the symbol if it includes an init priority, which this
patch doesn't change.

Before: __GLOBAL_I_a
Now: __GLOBAL_sub_I_myfile.cc
llvm-svn: 208128
2014-05-06 20:32:45 +00:00
Stephen Lin 4362261b00 CHECK-LABEL-ify some code gen tests to improve diagnostic experience when tests fail.
llvm-svn: 188447
2013-08-15 06:47:53 +00:00
John McCall 882987f30c Use the actual ABI-determined C calling convention for runtime
calls and declarations.

LLVM has a default CC determined by the target triple.  This is
not always the actual default CC for the ABI we've been asked to
target, and so we sometimes find ourselves annotating all user
functions with an explicit calling convention.  Since these
calling conventions usually agree for the simple set of argument
types passed to most runtime functions, using the LLVM-default CC
in principle has no effect.  However, the LLVM optimizer goes
into histrionics if it sees this kind of formal CC mismatch,
since it has no concept of CC compatibility.  Therefore, if this
module happens to define the "runtime" function, or got LTO'ed
with such a definition, we can miscompile;  so it's quite
important to get this right.

Defining runtime functions locally is quite common in embedded
applications.

llvm-svn: 176286
2013-02-28 19:01:20 +00:00