Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.
Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.
Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert
Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D73865
For consistency with normal instructions and clarity when reading IR,
it's best to print the %0, %1, ... names of function arguments in
definitions.
Also modifies the parser to accept IR in that form for obvious reasons.
llvm-svn: 367755
This introduced MMX instructions in code that wasn't previously using
them, breaking programs using 64-bit vectors and x87 floating-point in
the same application. See discussion on the code review for more
details.
> According to System V i386 ABI: the __m64 type paramater and return
> value are passed by MMX registers. But current implementation treats
> __m64 as i64 which results in parameter passing by stack and returning
> by EDX and EAX.
>
> This patch fixes the bug (https://bugs.llvm.org/show_bug.cgi?id=41029)
> for Linux and NetBSD.
>
> Patch by Wei Xiao (wxiao3)
>
> Differential Revision: https://reviews.llvm.org/D59744
llvm-svn: 363790
According to System V i386 ABI: the __m64 type paramater and return
value are passed by MMX registers. But current implementation treats
__m64 as i64 which results in parameter passing by stack and returning
by EDX and EAX.
This patch fixes the bug (https://bugs.llvm.org/show_bug.cgi?id=41029)
for Linux and NetBSD.
Patch by Wei Xiao (wxiao3)
Differential Revision: https://reviews.llvm.org/D59744
llvm-svn: 363116
LLVM IR recently added a Type parameter to the byval Attribute, so that
when pointers become opaque and no longer have an element type the
information will still be present in IR.
For now the Type parameter is optional (which is why Clang didn't need
this change at the time), but it will become mandatory soon.
llvm-svn: 362652
According to i386 System V ABI 2.1: Structures and unions assume the
alignment of their most strictly aligned component. But current
implementation always takes them as 4-byte aligned which will result
in incorrect code, e.g:
1 #include <immintrin.h>
2 typedef union {
3 int d[4];
4 __m128 m;
5 } M128;
6 extern void foo(int, ...);
7 void test(void)
8 {
9 M128 a;
10 foo(1, a);
11 foo(1, a.m);
12 }
The first call (line 10) takes the second arg as 4-byte aligned while
the second call (line 11) takes the second arg as 16-byte aligned.
There is oxymoron for the alignment of the 2 calls because they should
be the same.
This patch fixes the bug by following i386 System V ABI and apply it to
Linux only since other System V OS (e.g Darwin, PS4 and FreeBSD) don't
want to spend any effort dealing with the ramifications of ABI breaks
at present.
Patch by Wei Xiao (wxiao3)
Differential Revision: https://reviews.llvm.org/D60748
llvm-svn: 361934
Note that because we don't usually touch the MMX registers anyway, all -mno-mmx needs to do is tweak the x86-32 calling convention a little for vectors that look like MMX vectors, and prevent the definition of __MMX__.
clang doesn't actually stop the user from using MMX inline asm operands or MMX builtins in -mno-mmx mode; as a QOI issue, it would be nice to diagnose, but I doubt it really matters much.
<rdar://problem/9694837>
llvm-svn: 134770
Fangrui Song