[ValueTracking] Move GlobalAlias handling to be after the max depth check in computeKnownBits()
GlobalAlias handling used to be after GlobalValue handling, which meant it was, in practice, dead code. r220165 moved GlobalAlias handling to be before GlobalValue handling, but also moved it to be before the max depth check, causing an assert due to a recursion depth limit violation.
This moves GlobalAlias handling forward to where it's safe, and changes the GlobalValue handling to only look at GlobalObjects.
Hal Finkel [Tue, 23 Dec 2014 09:45:06 +0000 (09:45 +0000)]
[PowerPC] Don't mark the return-address slot as immutable
It is tempting to mark the fixed stack slot used to store the return address as
immutable when lowering @llvm.returnaddress(i32 0). Unfortunately, within the
function, it is not completely immutable: it is written during the function
prologue. When using post-RA instruction scheduling, the prologue instructions
are available for scheduling, and we're not free to interchange the order of a
particular store in the prologue with loads from that stack location.
Hal Finkel [Tue, 23 Dec 2014 08:38:50 +0000 (08:38 +0000)]
[PowerPC] Don't attempt a 64-bit pow2 division on PPC32
In r224033, in moving the signed power-of-2 division expansion into
BuildSDIVPow2, I accidentally made it possible to attempt the lowering for a
64-bit division on PPC32. This later asserts.
Michael Liao [Tue, 23 Dec 2014 08:26:55 +0000 (08:26 +0000)]
[SimplifyCFG] Revise common code sinking
- Fix the case where more than 1 common instructions derived from the same
operand cannot be sunk. When a pair of value has more than 1 derived values
in both branches, only 1 derived value could be sunk.
- Replace BB1 -> (BB2, PN) map with joint value map, i.e.
map of (BB1, BB2) -> PN, which is more accurate to track common ops.
A cast that was introduced in r209007 was accidentally left in after the changes made to GlobalAlias rules in r210062. This crashes if the aliasee is a now-leggal ConstantExpr.
Ahmed Bougacha [Tue, 23 Dec 2014 06:07:31 +0000 (06:07 +0000)]
[ARM] Don't break alignment when combining base updates into load/stores.
r223862/r224203 tried to also combine base-updating load/stores.
There was a mistake there: the alignment was added as is as an operand to
the ARMISD::VLD/VST node. However, the VLD/VST selection logic doesn't care
about less-than-standard alignment attributes.
For example, no matter the alignment of a v2i64 load (say 1), SelectVLD picks
VLD1q64 (because of the memory type). But VLD1q64 ("vld1.64 {dXX, dYY}") is
8-aligned, per ARMARMv7a 3.2.1.
For the 1-aligned load, what we really want is VLD1q8.
This commit introduces bitcasts if necessary, and changes the vld/vst type to
one whose standard alignment matches the original load/store alignment.
Chandler Carruth [Tue, 23 Dec 2014 02:58:14 +0000 (02:58 +0000)]
Revert r224739: Debug info: Teach SROA how to update debug info for
fragmented variables.
This caused codegen to start crashing when we built somewhat large
programs with debug info and optimizations. 'check-msan' hit in, and
I suspect a bootstrap would as well. I mailed a test case to the
review thread.
Jim Grosbach [Tue, 23 Dec 2014 00:35:23 +0000 (00:35 +0000)]
X86: Don't over-align combined loads.
When combining consecutive loads+inserts into a single vector load,
we should keep the alignment of the base load. Doing otherwise can, and does,
lead to using overly aligned instructions. In the included test case, for
example, using a 32-byte vmovaps on a 16-byte aligned value. Oops.
Reid Kleckner [Mon, 22 Dec 2014 23:58:37 +0000 (23:58 +0000)]
Make musttail more robust for vector types on x86
Previously I tried to plug musttail into the existing vararg lowering
code. That turned out to be a mistake, because non-vararg calls use
significantly different register lowering, even on x86. For example, AVX
vectors are usually passed in registers to normal functions and memory
to vararg functions. Now musttail uses a completely separate lowering.
Hopefully this can be used as the basis for non-x86 perfect forwarding.
David Blaikie [Mon, 22 Dec 2014 23:12:42 +0000 (23:12 +0000)]
Remove dynamic allocation/indirection from GCOVBlocks owned by GCOVFunction
Since these are all created in the DenseMap before they are referenced,
there's no problem with pointer validity by the time it's required. This
removes another use of DeleteContainerSeconds/manual memory management
which I'm cleaning up from time to time.
Adrian Prantl [Mon, 22 Dec 2014 23:09:14 +0000 (23:09 +0000)]
Thumb1 frame lowering: Mark CFI instructions with the FrameSetup flag.
Followup to r224294:
ARM/AArch64: Attach the FrameSetup MIFlag to CFI instructions.
Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.
Chandler Carruth [Mon, 22 Dec 2014 22:46:00 +0000 (22:46 +0000)]
[SROA] Lift the logic for traversing the alloca slices one partition at
a time into a partition iterator and a Partition class.
There is a lot of knock-on simplification that this enables, largely
stemming from having a Partition object to refer to in lots of helpers.
I've only done a minimal amount of that because enoguh stuff is changing
as-is in this commit.
This shouldn't change any observable behavior. I've worked hard to
preserve the *exact* traversal semantics which were originally present
even though some of them make no sense. I'll be changing some of this in
subsequent commits now that the logic is carefully factored into
a reusable place.
The primary motivation for this change is to break the rewriting into
phases in order to support more intelligent rewriting. For example, I'm
planning to change how split loads and stores are rewritten to remove
the significant overuse of integer bit packing in the resulting code and
allow more effective secondary splitting of aggregates. For any of this
to work, they have to share the exact traversal logic.
LoopSimplify fails to simplify some loops (e.g. when indirect branches
are involved). In such situations, it can happen that an exit for L1 is
the header of L2. Thus, when we create PHIs in one of such exits we are
also inserting PHIs in L2 header.
This could break LCSSA form for L2 because these inserted PHIs can also
have uses in L2 exits, which are never handled in the current
implementation. Provide a fix for this corner case and test that we
don't assert/crash on that.
Reid Kleckner [Mon, 22 Dec 2014 22:10:08 +0000 (22:10 +0000)]
Fix Windows unwind info for functions in sections other than .text
Previously we assumed the section name had the form .text$foo, which is
what we used to do for inline functions. If the dollar wasn't present,
we'd put unwind data in the .pdata and .xdata sections for the main
.text section, which is incorrect.
Currently, when ctpop is supported for scalar types, the expansion of
@llvm.ctpop.vXiY uses vector element extractions, insertions and individual
calls to @llvm.ctpop.iY. When not, expansion with bit-math operations is used
for the scalar calls.
Local haswell measurements show that we can improve vector @llvm.ctpop.vXiY
expansion in some cases by using a using a vector parallel bit twiddling
approach, based on:
v = v - ((v >> 1) & 0x55555555);
v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
v = ((v + (v >> 4) & 0xF0F0F0F)
v = v + (v >> 8)
v = v + (v >> 16)
v = v & 0x0000003F
(from http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel)
When scalar ctpop isn't supported, the approach above performs better for
v2i64, v4i32, v4i64 and v8i32 (see numbers below). And even when scalar ctpop
is supported, this approach performs ~2x better for v8i32.
Here, x86_64 implies -march=corei7-avx without ctpop and x86_64h includes ctpop
support with -march=core-avx2.
Matt Arsenault [Sun, 21 Dec 2014 16:48:42 +0000 (16:48 +0000)]
Enable (sext x) == C --> x == (trunc C) combine
Extend the existing code which handles this for zext. This makes this
more useful for targets with ZeroOrNegativeOne BooleanContent and
obsoletes a custom combine SI uses for i1 setcc (sext(i1), 0, setne)
since the constant will now be shrunk to i1.
The ARM ARM states:
LDM/LDMIA/LDMFD:
The SP can be in the list. However, ARM deprecates using these instructions
with SP in the list.
ARM deprecates using these instructions with both the LR and the PC in the
list.
LDMDA/LDMFA/LDMDB/LDMEA/LDMIB/LDMED:
The SP can be in the list. However, instructions that include the SP in the
list are deprecated.
Instructions that include both the LR and the PC in the list are deprecated.
POP:
The SP can only be in the list before ARMv7. ARM deprecates any use of ARM
instructions that include the SP, and the value of the SP after such an
instruction is UNKNOWN.
ARM deprecates the use of this instruction with both the LR and the PC in
the list.
Attempt to diagnose use of deprecated forms of these instructions. This mirrors
the previous changes to diagnose use of the deprecated forms of STM in ARM mode.
David Majnemer [Sat, 20 Dec 2014 03:04:38 +0000 (03:04 +0000)]
InstSimplify: Optimize away pointless comparisons
(X & INT_MIN) ? X & INT_MAX : X into X & INT_MAX
(X & INT_MIN) ? X : X & INT_MAX into X
(X & INT_MIN) ? X | INT_MIN : X into X
(X & INT_MIN) ? X : X | INT_MIN into X | INT_MIN
Chandler Carruth [Sat, 20 Dec 2014 02:39:18 +0000 (02:39 +0000)]
[SROA] Run clang-format over the entire SROA pass as I wrote it before
much of the glory of clang-format, and now any time I touch it I risk
introducing formatting changes as part of a functional commit.
Also, clang-format is *way* better at formatting my code than I am.
Most of this is a huge improvement although I reverted a couple of
places where I hit a clang-format bug with lambdas that has been filed
but not (fully) fixed.
Chandler Carruth [Sat, 20 Dec 2014 02:19:22 +0000 (02:19 +0000)]
[x86] Change the test added in r223774 to first check the spelling of
the error message for a bogus processor, and then look specifically for
that error message using FileCheck.
I actually tried to write the test this way at first, but drew a blank
on how to ensure the error message stayed in sync (oops). Now that I've
recalled how to do that, this is clearly better.
It also fixes an issue with a malloc implementation that actually prints
to stderr in all cases, which was causing problems for some builders it
seems.
Matthias Braun [Sat, 20 Dec 2014 01:54:50 +0000 (01:54 +0000)]
LiveIntervalAnalysis: No kill flags for partially undefined uses.
We must not add kill flags when reading a vreg with some undefined
subregisters, if subreg liveness tracking is enabled. This is because
the register allocator may reuse these undefined subregisters for other
values which are not killed.
Eric Fiselier [Fri, 19 Dec 2014 22:29:12 +0000 (22:29 +0000)]
[LIT] Add JSONMetricValue type to wrap types supported by the json encoder.
Summary:
The following types can be encoded and decoded by the json library:
`dict`, `list`, `tuple`, `str`, `unicode`, `int`, `long`, `float`, `bool`, `NoneType`.
`JSONMetricValue` can be constructed with any of these types, and used as part of Test.Result.
This patch also adds a toMetricValue function that converts a value into a MetricValue.
Reid Kleckner [Fri, 19 Dec 2014 22:19:48 +0000 (22:19 +0000)]
Add the ExceptionHandling::MSVC enumeration
It is intended to be used for a family of personality functions that
have similar IR preparation requirements. Typically when interoperating
with MSVC personality functions, bits of functionality need to be
outlined from the main function into helper functions. There is also
usually more than one landing pad per invoke, which does not match the
LLVM IR landingpad representation.
None of this is implemented yet. This change just adds a new enum that
is active for *-windows-msvc and delegates to the EH removal preparation
pass. No functionality change for other targets.
Sanjay Patel [Fri, 19 Dec 2014 22:16:28 +0000 (22:16 +0000)]
Model sqrtss as a binary operation with one source operand tied to the destination (PR14221)
This is a continuation of r167064 ( http://llvm.org/viewvc/llvm-project?view=revision&revision=167064 ).
That patch started to fix PR14221 ( http://llvm.org/bugs/show_bug.cgi?id=14221 ), but it was not completed.
Sanjay Patel [Fri, 19 Dec 2014 20:23:41 +0000 (20:23 +0000)]
merge consecutive stores of extracted vector elements
Add a path to DAGCombiner::MergeConsecutiveStores()
to combine multiple scalar stores when the store operands
are extracted vector elements. This is a partial fix for
PR21711 ( http://llvm.org/bugs/show_bug.cgi?id=21711 ).
Frederic Riss [Fri, 19 Dec 2014 18:26:33 +0000 (18:26 +0000)]
[DebugInfo] Move all DWARF headers to the public include directory.
dsymutil needs access to DWARF specific inforamtion, the small DIContext
wrapper isn't sufficient. Other DWARF consumers might want to use it too
(I'm looking at you lldb).
Reapply: [InstCombine] Fix visitSwitchInst to use right operand types for sub cstexpr
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. Also, fix code to also return the modified switch when only
the truncation is performed.
Revert "[InstCombine] Fix visitSwitchInst to use right operand types for sub cstexpr"
Reverts commit r224574 to appease buildbots:
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. This fixes an assertion crash.
[InstCombine] Fix visitSwitchInst to use right operand types for sub cstexpr
The visitSwitchInst generates SUB constant expressions to recompute the
switch condition. When truncating the condition to a smaller type, SUB
expressions should use the previous type (before trunc) for both
operands. This fixes an assertion crash.
Export symbols in libLTO.dylib for the local context-related functions
added in r221733 (`LTO_API_VERSION=11`)... and add the missing
definition for `lto_codegen_create_in_local_context()`.
Instead of reusing the name `MapValue()` when mapping `Metadata`, use
`MapMetadata()`. The old name doesn't make much sense after the
`Metadata`/`Value` split.
Matthias Braun [Fri, 19 Dec 2014 01:39:46 +0000 (01:39 +0000)]
RegisterCoalescer: rewrite eliminateUndefCopy().
This also fixes problems with undef copies of subregisters. I can't
attach a testcase for that as none of the targets in trunk has
subregister liveness tracking enabled.