Commit Graph

7 Commits

Author SHA1 Message Date
Chandler Carruth 05920b1847 Fix the root cause of PR15348 by correctly handling alignment 0 on
memory intrinsics in the SDAG builder.

When alignment is zero, the lang ref says that *no* alignment
assumptions can be made. This is the exact opposite of the internal API
contracts of the DAG where alignment 0 indicates that the alignment can
be made to be anything desired.

There is another, more explicit alignment that is better suited for the
role of "no alignment at all": an alignment of 1. Map the intrinsic
alignment to this early so that we don't end up generating aligned DAGs.

It is really terrifying that we've never seen this before, but we
suddenly started generating a large number of alignment 0 memcpys due to
the new code to do memcpy-based copying of POD class members. That patch
contains a bug that rounds bitfield alignments down when they are the
first field. This can in turn produce zero alignments.

This fixes weird crashes I've seen in library users of LLVM on 32-bit
hosts, etc.

llvm-svn: 176022
2013-02-25 14:20:21 +00:00
NAKAMURA Takumi 902b137133 llvm/test/CodeGen/X86/memset.ll: FileCheck-ize, and add another case on +avx.
llvm-svn: 167975
2012-11-14 21:01:40 +00:00
Benjamin Kramer d71fb86aed Force CPU in test so we don't accidentally get AVX code on an AVX-capable host.
llvm-svn: 167973
2012-11-14 20:31:42 +00:00
Chris Lattner 80ed9dc9e5 rip out a ton of intrinsic modernization logic from AutoUpgrade.cpp, which is
for pre-2.9 bitcode files.  We keep x86 unaligned loads, movnt, crc32, and the
target indep prefetch change.

As usual, updating the testsuite is a PITA.

llvm-svn: 133337
2011-06-18 06:05:24 +00:00
Dan Gohman 40503396da Eliminate more uses of llvm-as and llvm-dis.
llvm-svn: 81290
2009-09-08 23:54:48 +00:00
Nick Lewycky 213e114a2c The Linux ABI emits an extra "movl %esp, %ebp" in function prologue and
sometimes a "mov %ebp, %esp" in the epilogue.

Force these tests that rely on counting 'mov' to use i686-apple-darwin8.8.0
where they were written.

llvm-svn: 51568
2008-05-26 20:18:56 +00:00
Evan Cheng a1100782d5 Add a couple of test cases.
llvm-svn: 51441
2008-05-22 21:19:19 +00:00