Add myself as the code owner for the scoped-noalias metadata I've developed.

llvm-svn: 213950

This functionality is currently turned off by default.

Part of the motivation for introducing scoped-noalias metadata is to enable the
preservation of noalias parameter attribute information after inlining.
Sometimes this can be inferred from the code in the caller after inlining, but
often we simply lose valuable information.

The overall process if fairly simple:
 1. Create a new unqiue scope domain.
 2. For each (used) noalias parameter, create a new alias scope.
 3. For each pointer, collect the underlying objects. Add a noalias scope for
    each noalias parameter from which we're not derived (and has not been
    captured prior to that point).
 4. Add an alias.scope for each noalias parameter from which we might be
    derived (or has been captured before that point).

Note that the capture checks apply only if one of the underlying objects is not
an identified function-local object.

llvm-svn: 213949

In the process of fixing the noalias parameter -> metadata conversion process
that will take place during inlining (which will be committed soon, but not
turned on by default), I have come to realize that the semantics provided by
yesterday's commit are not really what we want. Here's why:

void foo(noalias a, noalias b, noalias c, bool x) {
  *q = x ? a : b;
  *c = *q;
}

Generically, we know that *c does not alias with *a and with *b (so there is an
'and' in what we know we're not), and we know that *q might be derived from *a
or from *b (so there is an 'or' in what we know that we are). So we do not want
the semantics currently, where any noalias scope matching any alias.scope
causes a NoAlias return. What we want to know is that the noalias scopes form a
superset of the alias.scope list (meaning that all the things we know we're not
is a superset of all of things the other instruction might be).

Making that change, however, introduces a composibility problem. If we inline
once, adding the noalias metadata, and then inline again adding more, and we
append new scopes onto the noalias and alias.scope lists each time. But, this
means that we could change what was a NoAlias result previously into a MayAlias
result because we appended an additional scope onto one of the alias.scope
lists. So, instead of giving scopes the ability to have parents (which I had
borrowed from the TBAA implementation, but seems increasingly unlikely to be
useful in practice), I've given them domains. The subset/superset condition now
applies within each domain independently, and we only need it to hold in one
domain. Each time we inline, we add the new scopes in a new scope domain, and
everything now composes nicely. In addition, this simplifies the
implementation.

llvm-svn: 213948

The dragonegg buildbot (and others?) started failing after
r213945/r213946 because `llvm-as` wasn't linking in the bitcode reader.
I think moving the verify functions to the same file as the verify pass
should fix the build.  Adding a command-line option for maintaining
use-list order in assembly as a drive-by to prevent warnings about
unused static functions.

llvm-svn: 213947

llvm-svn: 213946

Add a -verify-use-list-order pass, which shuffles use-list order, writes
to bitcode, reads back, and verifies that the (shuffled) order matches.

  - The utility functions live in lib/IR/UseListOrder.cpp.

  - Moved (and renamed) the command-line option to enable writing
    use-lists, so that this pass can return early if the use-list orders
    aren't being serialized.

It's not clear that this pass is the right direction long-term (perhaps
a separate tool instead?), but short-term it's a great way to test the
use-list order prototype.  I've added an XFAIL-ed testcase that I'm
hoping to get working pretty quickly.

This is part of PR5680.

llvm-svn: 213945

Patch by Ben Foster!

Differential Revision: http://reviews.llvm.org/D4657

llvm-svn: 213944

No functionality change.

llvm-svn: 213938

be disabled in CMake or relocated if desired.

llvm-svn: 213936

llvm-svn: 213933

It sometimes confuses FileCheck. Consider the case that path contains 'stmib'. :)

llvm-svn: 213932

SDValues, fixing the two bugs left in the regression suite.

The key for both of these was the use a single value type rather than
a VTList which caused an unintentionally single-result merge-value node.
Fix this by getting the appropriate VTList in place.

Doing this exposed that the comments in x86's code abouth how MUL_LOHI
operands are handle is wrong. The bug with the use of out-of-range
result numbers was hiding the bug about the order of operands here (as
best i can tell). There are more places where the code appears to get
this backwards still...

llvm-svn: 213931

doesn't actually correspond to an SDValue at all. Fixes most of the
remaining asserts on out-of-range SDValue result numbers.

llvm-svn: 213930

llvm-svn: 213928

with a result number outside the range of results for the node.

I don't know how we managed to not really check this very basic
invariant for so long, but the code is *very* broken at this point.
I have over 270 test failures with the assert enabled. I'm committing it
disabled so that others can join in the cleanup effort and reproduce the
issues. I've also included one of the obvious fixes that I already
found. More fixes to come.

llvm-svn: 213926

assembly instructions.

This is necessary to ensure ARM assembler switches to Thumb mode before it
starts assembling the file level inline assembly instructions at the beginning
of a .s file.

<rdar://problem/17757232>

llvm-svn: 213924

testcases.

Based on code review from Philip Reames. Thanks Philip!

llvm-svn: 213923

StringMap doesn't guarantee any particular iteration order,
this is suboptimal when comparing llvm-vtabledump's output for two
object files.

llvm-svn: 213921

llvm-svn: 213920

feedback from Eric Christopher.

No functional change.

llvm-svn: 213917

Because the PowerPC vmrgh* and vmrgl* instructions have a built-in
big-endian bias, it is necessary to swap their inputs in little-endian
mode when using them to implement a vector shuffle.  This was
previously missed in the vector LE implementation.

There was already logic to distinguish between unary and "normal"
vmrg* vector shuffles, so this patch extends that logic to use a third
option:  "swapped" vmrg* vector shuffles that are used for little
endian in place of the "normal" ones.

I've updated the vec-shuffle-le.ll test to check for the expected
register ordering on the generated instructions.

This bug was discovered when testing the LE and ELFv2 patches for
safety if they were backported to 3.4.  A different vectorization
decision was made in 3.4 than on mainline trunk, and that exposed the
problem.  I've verified this fix takes care of that issue.

llvm-svn: 213915

This patch implements the data structures, the reader and
the writers for the new code coverage mapping system. 
The new code coverage mapping system uses the instrumentation
based profiling to provide code coverage analysis.

llvm-svn: 213910

This patch implements the data structures, the reader and
the writers for the new code coverage mapping system. 
The new code coverage mapping system uses the instrumentation
based profiling to provide code coverage analysis.

llvm-svn: 213909

The -print-file-name option in llvm-nm is to precede each symbol
with the object file it came from.  While code for the parsing of this
option and its aliases existed there was no code to implement it.

llvm-svn: 213906

A builder complained that it couldn't find llvm-vtabledump, this is
probably because it wasn't a dependency of the 'test' target.

llvm-svn: 213905

This tool's job is to dump the vtables inside object files.  It is
currently limited to MS ABI vf- and vb-tables but it will eventually
support Itanium-style v-tables as well.

Differential Revision: http://reviews.llvm.org/D4584

llvm-svn: 213903

hint) the loop unroller replaces the llvm.loop.unroll.count metadata with
llvm.loop.unroll.disable metadata to prevent any subsequent unrolling
passes from unrolling more than the hint indicates.  This patch fixes
an issue where loop unrolling could be disabled for other loops as well which
share the same llvm.loop metadata.

llvm-svn: 213900

llvm-svn: 213899

which have successfully round-tripped through the combine phase, and use
this to ensure all operands to DAG nodes are visited by the combiner,
even if they are only added during the combine phase.

This is critical to have the combiner reach nodes that are *introduced*
during combining. Previously these would sometimes be visited and
sometimes not be visited based on whether they happened to end up on the
worklist or not. Now we always run them through the combiner.

This fixes quite a few bad codegen test cases lurking in the suite while
also being more principled. Among these, the TLS codegeneration is
particularly exciting for programs that have this in the critical path
like TSan-instrumented binaries (although I think they engineer to use
a different TLS that is faster anyways).

I've tried to check for compile-time regressions here by running llc
over a merged (but not LTO-ed) clang bitcode file and observed at most
a 3% slowdown in llc. Given that this is essentially a worst case (none
of opt or clang are running at this phase) I think this is tolerable.
The actual LTO case should be even less costly, and the cost in normal
compilation should be negligible.

With this combining logic, it is possible to re-legalize as we combine
which is necessary to implement PSHUFB formation on x86 as
a post-legalize DAG combine (my ultimate goal).

Differential Revision: http://reviews.llvm.org/D4638

llvm-svn: 213898

vector operation legalization with support for custom target lowering
and fallback to expand when it fails, and use this to implement sext and
anyext load lowering for x86 in a more principled way.

Previously, the x86 backend relied on a target DAG combine to "combine
away" sextload and extload nodes prior to legalization, or would expand
them during legalization with terrible code. This is particularly
problematic because the DAG combine relies on running over non-canonical
DAG nodes at just the right time to match several common and important
patterns. It used a combine rather than lowering because we didn't have
good lowering support, and to expose some tricks being employed to more
combine phases.

With this change it becomes a proper lowering operation, the backend
marks that it can lower these nodes, and I've added support for handling
the canonical forms that don't have direct legal representations such as
sextload of a v4i8 -> v4i64 on AVX1. With this change, our test cases
for this behavior continue to pass even after the DAG combiner beigns
running more systematically over every node.

There is some noise caused by this in the test suite where we actually
use vector extends instead of subregister extraction. This doesn't
really seem like the right thing to do, but is unlikely to be a critical
regression. We do regress in one case where by lowering to the
target-specific patterns early we were able to combine away extraneous
legal math nodes. However, this regression is completely addressed by
switching to a widening based legalization which is what I'm working
toward anyways, so I've just switched the test to that mode.

Differential Revision: http://reviews.llvm.org/D4654

llvm-svn: 213897

The Microsoft ABI and MSVCRT are considered the canonical C runtime and ABI.
The long double routines are not part of this environment.  However, cygwin and
MinGW both provide supplementary implementations.  Change the condition to
reflect this reality.

llvm-svn: 213896

llvm-svn: 213895

Even if there's a file called c:\a, we want /? to be preserved as
an option, not expanded to a filename.

llvm-svn: 213894

This patch minimizes the number of nops that must be emitted on X86 to satisfy
stackmap shadow constraints.

To minimize the number of nops inserted, the X86AsmPrinter now records the
size of the most recent stackmap's shadow in the StackMapShadowTracker class,
and tracks the number of instruction bytes emitted since the that stackmap
instruction was encountered. Padding is emitted (if it is required at all)
immediately before the next stackmap/patchpoint instruction, or at the end of
the basic block.

This optimization should reduce code-size and improve performance for people
using the llvm stackmap intrinsic on X86.

<rdar://problem/14959522>

llvm-svn: 213892

Frontends are responsible for putting inalloca on parameters that would
be passed in memory and not registers.

llvm-svn: 213891

llvm-svn: 213890

llvm-svn: 213884

This target is identical to the Windows MSVC (and follows Microsoft ABI for C).
Correct the library call setup for this target.  The same set of library calls
are missing on this environment.

llvm-svn: 213883

llvm-svn: 213882

llvm-svn: 213880