Math functions are mark as readonly because they read the floating point
rounding mode. Because we don't vectorize loops that would contain function
calls that set the rounding mode it is safe to ignore this memory read.
llvm-svn: 185299
This allows clang to use the backend parameter attribute 'returned' when generating 'this'-returning constructors and destructors in ARM and MSVC C++ ABIs.
llvm-svn: 185291
before the value computation of the result. In C, this is implied by there being
a sequence point after their evaluation, and in C++, it's implied by the
side-effects being sequenced before the expressions and statements in the
function body.
llvm-svn: 185282
standard's rule that an extern "C" declaration conflicts with any entity in the
global scope with the same name. Now we only care if the global scope entity is
a variable declaration (and so might have the same mangled name as the extern
"C" declaration). This has been reported as a standard defect.
Original commit message:
PR7927, PR16247: Reimplement handling of matching extern "C" declarations
across scopes.
When we declare an extern "C" name that is not a redeclaration of an entity in
the same scope, check whether it redeclares some extern "C" entity from another
scope, and if not, check whether it conflicts with a (non-extern-"C") entity in
the translation unit.
When we declare a name in the translation unit that is not a redeclaration,
check whether it conflicts with any extern "C" entities (possibly from other
scopes).
llvm-svn: 185281
explicitly specify use of C++98 or C++11. Lang_CXX is preserved as
an alias for Lang_CXX98.
This does not add Lang_CXX1Y or Lang_C11, on the assumption that it's
better to add them if/when they are needed.
(This is a prerequisite for a test in a later patch for RecursiveASTVisitor.)
Reviewed by Richard Smith.
llvm-svn: 185276
code to specify what version of POSIX the system should provide. If
you want to check what version of POSIX is actually available, you're
supposed to test _POSIX_VERSION.
However, since sysconf() has been in POSIX since 1995, it's probably
safe to assume it's available on any system with a C++11 compiler,
especially if _SC_NPROCESSORS_ONLN is defined too. So no point in a
complicated preprocessor rule if just we unconditionally include
<unistd.h> (on non-Windows systems).
Also, I've added a #warning for to help porters detect when a suitable
implementation isn't detected at compile-time.
Howard: Matthew, can you patch CREDITS.TXT? Thanks.
llvm-svn: 185275
Orignally, we first test if a ValueMap contains a Value, and than use the
index operator to get the corresponding new value. This requires the ValueMap
to lookup the key (i.e. the old value) twice.
Now, we directly use the "lookup" function provided by DenseMap to implement
the same functionality.
llvm-svn: 185260
Changing the sign when comparing the base pointer would introduce all
sorts of unexpected things like:
%gep.i = getelementptr inbounds [1 x i8]* %a, i32 0, i32 0
%gep2.i = getelementptr inbounds [1 x i8]* %b, i32 0, i32 0
%cmp.i = icmp ult i8* %gep.i, %gep2.i
%cmp.i1 = icmp ult [1 x i8]* %a, %b
%cmp = icmp ne i1 %cmp.i, %cmp.i1
ret i1 %cmp
into:
%cmp.i = icmp slt [1 x i8]* %a, %b
%cmp.i1 = icmp ult [1 x i8]* %a, %b
%cmp = xor i1 %cmp.i, %cmp.i1
ret i1 %cmp
By preserving the original sign, we now get:
ret i1 false
This fixes PR16483.
llvm-svn: 185259
Rui Ueyama