DFSan changes the ABI of each function in the module. This makes it possible
for a function with the native ABI to be called with the instrumented ABI,
or vice versa, thus possibly invoking undefined behavior. A simple way
of statically detecting instances of this problem is to prepend the prefix
"dfs$" to the name of each instrumented-ABI function.
This will not catch every such problem; in particular function pointers passed
across the instrumented-native barrier cannot be used on the other side.
These problems could potentially be caught dynamically.
Differential Revision: http://llvm-reviews.chandlerc.com/D1373
llvm-svn: 189052
A single metadata will not span multiple lines. This also helps me with
my script to automatic update the testing cases.
A debug info testing case should have a llvm.dbg.cu.
Do not use hard-coded id for debug nodes.
llvm-svn: 189033
I don't actually have a version of autoconf so I edited configure directly
as well. It's copy-pasted so I think there was little margin for error.
See also Clang-side dependency graph changes.
llvm-svn: 189026
The instruction to convert between floating point and fixed point representations
takes an immediate operand for the number of fractional bits of the fixed point
value. ARMARM specifies that when that number of bits is zero, the assembler
should encode floating point/integer conversion instructions.
This patch adds the necessary instruction aliases to achieve this behaviour.
llvm-svn: 189009
using GEPs. Previously, it used a number of different heuristics for
analyzing the GEPs. Several of these were conservatively correct, but
failed to fall back to SCEV even when SCEV might have given a reasonable
answer. One was simply incorrect in how it was formulated.
There was good code already to recursively evaluate the constant offsets
in GEPs, look through pointer casts, etc. I gathered this into a form
code like the SLP code can use in a previous commit, which allows all of
this code to become quite simple.
There is some performance (compile time) concern here at first glance as
we're directly attempting to walk both pointers constant GEP chains.
However, a couple of thoughts:
1) The very common cases where there is a dynamic pointer, and a second
pointer at a constant offset (usually a stride) from it, this code
will actually not do any unnecessary work.
2) InstCombine and other passes work very hard to collapse constant
GEPs, so it will be rare that we iterate here for a long time.
That said, if there remain performance problems here, there are some
obvious things that can improve the situation immensely. Doing
a vectorizer-pass-wide memoizer for each individual layer of pointer
values, their base values, and the constant offset is likely to be able
to completely remove redundant work and strictly limit the scaling of
the work to scrape these GEPs. Since this optimization was not done on
the prior version (which would still benefit from it), I've not done it
here. But if folks have benchmarks that slow down it should be straight
forward for them to add.
I've added a test case, but I'm not really confident of the amount of
testing done for different access patterns, strides, and pointer
manipulation.
llvm-svn: 189007
pointers, but accumulate the offset into an APInt in the process of
stripping it.
This is a pretty handy thing to have, such as when trying to determine
if two pointers are at some constant relative offset. I'll be committing
a patch shortly to use it for exactly that purpose.
llvm-svn: 189000
Value. These methods probably don't belong here, and I'm discussing
moving the lot of them to a better home, but for now I'm about to extend
their functionality and wanted to tidy them up first.
llvm-svn: 188997
Back in the mists of time (2008), it seems TableGen couldn't handle the
patterns necessary to match ARM's CMOV node that we convert select operations
to, so we wrote a lot of fairly hairy C++ to do it for us.
TableGen can deal with it now: there were a few minor differences to CodeGen
(see tests), but nothing obviously worse that I could see, so we should
probably address anything that *does* come up in a localised manner.
llvm-svn: 188995
When truncated vector stores were being custom lowered in
VectorLegalizer::LegalizeOp(), the old (illegal) and new (legal) node pair
was not being added to LegalizedNodes list. Instead of the legalized
result being passed to VectorLegalizer::TranslateLegalizeResult(),
the result was being passed back into VectorLegalizer::LegalizeOp(),
which ended up adding a (new, new) pair to the list instead.
This was causing an assertion failure when a custom lowered truncated
vector store was the last instruction a basic block and the VectorLegalizer
was unable to find it in the LegalizedNodes list when updating the
DAG root.
llvm-svn: 188953
The small utility function that pattern matches Base + Index +
Offset patterns for loads and stores fails to recognize the base
pointer for loads/stores from/into an array at offset 0 inside a
loop. As a result DAGCombiner::MergeConsecutiveStores was not able
to merge all stores.
This commit fixes the issue by adding an additional pattern match
and also a test case.
Reviewer: Nadav
llvm-svn: 188936
Summary:
This support will be utilized in things like clang to help check printf
format specifiers that are only valid when using the VSCRT.
Reviewers: rnk, asl, chandlerc
Reviewed By: chandlerc
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1455
llvm-svn: 188935
