Commit Graph

2300 Commits

Author SHA1 Message Date
Peter Collingbourne 78f1ecc59c ARM: When spilling extra registers for alignment, prefer low registers on all Thumb targets.
This makes it more likely that we can use the 16-bit push and pop instructions
on Thumb-2, saving around 4 bytes per function.

Differential Revision: http://reviews.llvm.org/D9165

llvm-svn: 235637
2015-04-23 20:31:26 +00:00
Peter Collingbourne 1213918bf4 ARM: Only enforce 4-byte alignment on Thumb-2 functions with constant pools.
This appears to have been introduced back in r76698 as part of an unrelated
change. I can find no official ARM documentation stating that Thumb-2 functions
require 4-byte alignment; in fact, ARM documentation appears to contradict
this (see, e.g., ARM Architecture Reference Manual Thumb-2 Supplement,
section 2.6.1: "Thumb-2 enforces 16-bit alignment on all instructions.").

Also remove code that sets alignment for ARM functions, which is redundant
with code in the MachineFunction constructor, and remove the hidden
-arm-align-constant-islands flag, which has been enabled by default since
r146739 (Dec 2011) and has probably received sufficient testing by now.

Differential Revision: http://reviews.llvm.org/D9138

llvm-svn: 235636
2015-04-23 20:31:22 +00:00
Hans Wennborg 0867b151c9 Re-commit r235560: Switch lowering: extract jump tables and bit tests before building binary tree (PR22262)
Third time's the charm. The previous commit was reverted as a
reverse for-loop in SelectionDAGBuilder::lowerWorkItem did 'I--'
on an iterator at the beginning of a vector, causing asserts
when using debugging iterators. This commit fixes that.

llvm-svn: 235608
2015-04-23 16:45:24 +00:00
Aaron Ballman 0be238cebd Revert r235560; this commit was causing several failed assertions in Debug builds using MSVC's STL. The iterator is being used outside of its valid range.
llvm-svn: 235597
2015-04-23 13:41:59 +00:00
Hans Wennborg 15823d49b6 Switch lowering: extract jump tables and bit tests before building binary tree (PR22262)
This is a re-commit of r235101, which also fixes the problems with the previous patch:

- Switches with only a default case and non-fallthrough were handled incorrectly

- The previous patch tickled a bug in PowerPC Early-Return Creation which is fixed here.

> This is a major rewrite of the SelectionDAG switch lowering. The previous code
> would lower switches as a binary tre, discovering clusters of cases
> suitable for lowering by jump tables or bit tests as it went along. To increase
> the likelihood of finding jump tables, the binary tree pivot was selected to
> maximize case density on both sides of the pivot.
>
> By not selecting the pivot in the middle, the binary trees would not always
> be balanced, leading to performance problems in the generated code.
>
> This patch rewrites the lowering to search for clusters of cases
> suitable for jump tables or bit tests first, and then builds the binary
> tree around those clusters. This way, the binary tree will always be balanced.
>
> This has the added benefit of decoupling the different aspects of the lowering:
> tree building and jump table or bit tests finding are now easier to tweak
> separately.
>
> For example, this will enable us to balance the tree based on profile info
> in the future.
>
> The algorithm for finding jump tables is quadratic, whereas the previous algorithm
> was O(n log n) for common cases, and quadratic only in the worst-case. This
> doesn't seem to be major problem in practice, e.g. compiling a file consisting
> of a 10k-case switch was only 30% slower, and such large switches should be rare
> in practice. Compiling e.g. gcc.c showed no compile-time difference.  If this
> does turn out to be a problem, we could limit the search space of the algorithm.
>
> This commit also disables all optimizations during switch lowering in -O0.
>
> Differential Revision: http://reviews.llvm.org/D8649

llvm-svn: 235560
2015-04-22 23:14:56 +00:00
Pirama Arumuga Nainar 80f958dbf4 Fix flakiness in fp16-promote.ll
Summary:
In the f16-promote test, make the checks for native conversion instructions
similar to the libcall checks:
- Remove hard coded register names
- Do not check exact instruction sequences.

This fixes test flakiness due to non-determinism in instruction
scheduling and register allocation.  I also fixed a few minor things in
the CHECK-LIBCALL checks.

I'll try to find a way to check that unnecessary loads, stores, or
conversions don't happen.

Reviewers: mzolotukhin, srhines, ab

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9112

llvm-svn: 235363
2015-04-20 23:54:41 +00:00
Ahmed Bougacha 279e3ee954 [GlobalMerge] Look at uses to create smaller global sets.
Instead of merging everything together, look at the users of
GlobalVariables, and try to group them by function, to create
sets of globals used "together".

Using that information, a less-aggressive alternative is to keep merging
everything together *except* globals that are only ever used alone, that
is, those for which it's clearly non-profitable to merge with others.

In my testing, grouping by Function is too aggressive, but grouping by
BasicBlock is too conservative.  Anything in-between isn't trivially
available, so stick with Function grouping for now.

cl::opts are added for testing; both enabled by default.

A few of the testcases aren't testing the merging proper, but just
various edge cases when merging does occur.  Update them to use the
previous grouping behavior. Also, one of the tests is unrelated to
GlobalMerge; change it accordingly.
While there, switch to r234666' flags rather than the brutal -O3.

Differential Revision: http://reviews.llvm.org/D8070

llvm-svn: 235249
2015-04-18 01:21:58 +00:00
Pirama Arumuga Nainar db7c07e2bf Add support to promote f16 to f32
Summary:
This patch adds legalization support to operate on FP16 as a load/store type
and do operations on it as floats.

Tests for ARM are added to test/CodeGen/ARM/fp16-promote.ll

Reviewers: srhines, t.p.northover

Differential Revision: http://reviews.llvm.org/D8755

llvm-svn: 235215
2015-04-17 18:36:25 +00:00
David Blaikie 23af64846f [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction
See r230786 and r230794 for similar changes to gep and load
respectively.

Call is a bit different because it often doesn't have a single explicit
type - usually the type is deduced from the arguments, and just the
return type is explicit. In those cases there's no need to change the
IR.

When that's not the case, the IR usually contains the pointer type of
the first operand - but since typed pointers are going away, that
representation is insufficient so I'm just stripping the "pointerness"
of the explicit type away.

This does make the IR a bit weird - it /sort of/ reads like the type of
the first operand: "call void () %x(" but %x is actually of type "void
()*" and will eventually be just of type "ptr". But this seems not too
bad and I don't think it would benefit from repeating the type
("void (), void () * %x(" and then eventually "void (), ptr %x(") as has
been done with gep and load.

This also has a side benefit: since the explicit type is no longer a
pointer, there's no ambiguity between an explicit type and a function
that returns a function pointer. Previously this case needed an explicit
type (eg: a function returning a void() function was written as
"call void () () * @x(" rather than "call void () * @x(" because of the
ambiguity between a function returning a pointer to a void() function
and a function returning void).

No ambiguity means even function pointer return types can just be
written alone, without writing the whole function's type.

This leaves /only/ the varargs case where the explicit type is required.

Given the special type syntax in call instructions, the regex-fu used
for migration was a bit more involved in its own unique way (as every
one of these is) so here it is. Use it in conjunction with the apply.sh
script and associated find/xargs commands I've provided in rr230786 to
migrate your out of tree tests. Do let me know if any of this doesn't
cover your cases & we can iterate on a more general script/regexes to
help others with out of tree tests.

About 9 test cases couldn't be automatically migrated - half of those
were functions returning function pointers, where I just had to manually
delete the function argument types now that we didn't need an explicit
function type there. The other half were typedefs of function types used
in calls - just had to manually drop the * from those.

import fileinput
import sys
import re

pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)')
addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$")
func_end = re.compile("(?:void.*|\)\s*)\*$")

def conv(match, line):
  if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)):
    return line
  return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():]

for line in sys.stdin:
  sys.stdout.write(conv(re.search(pat, line), line))

llvm-svn: 235145
2015-04-16 23:24:18 +00:00
Hans Wennborg a9e2057416 Revert the switch lowering change (r235101, r235103, r235106)
Looks like it broke the sanitizer-ppc64-linux1 build. Reverting for now.

llvm-svn: 235108
2015-04-16 15:43:26 +00:00
Hans Wennborg d403664ed8 Switch lowering: extract jump tables and bit tests before building binary tree (PR22262)
This is a major rewrite of the SelectionDAG switch lowering. The previous code
would lower switches as a binary tre, discovering clusters of cases
suitable for lowering by jump tables or bit tests as it went along. To increase
the likelihood of finding jump tables, the binary tree pivot was selected to
maximize case density on both sides of the pivot.

By not selecting the pivot in the middle, the binary trees would not always
be balanced, leading to performance problems in the generated code.

This patch rewrites the lowering to search for clusters of cases
suitable for jump tables or bit tests first, and then builds the binary
tree around those clusters. This way, the binary tree will always be balanced.

This has the added benefit of decoupling the different aspects of the lowering:
tree building and jump table or bit tests finding are now easier to tweak
separately.

For example, this will enable us to balance the tree based on profile info
in the future.

The algorithm for finding jump tables is O(n^2), whereas the previous algorithm
was O(n log n) for common cases, and quadratic only in the worst-case. This
doesn't seem to be major problem in practice, e.g. compiling a file consisting
of a 10k-case switch was only 30% slower, and such large switches should be rare
in practice. Compiling e.g. gcc.c showed no compile-time difference.  If this
does turn out to be a problem, we could limit the search space of the algorithm.

This commit also disables all optimizations during switch lowering in -O0.

Differential Revision: http://reviews.llvm.org/D8649

llvm-svn: 235101
2015-04-16 14:49:23 +00:00
Duncan P. N. Exon Smith 62e0f454a0 DebugInfo: Remove 'inlinedAt:' field from MDLocalVariable
Remove 'inlinedAt:' from MDLocalVariable.  Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.

The 'inlinedAt:' field was used by the backend in two ways:

 1. To tell the backend whether and into what a variable was inlined.
 2. To create a unique id for each inlined variable.

Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).

This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.

If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.

llvm-svn: 235050
2015-04-15 22:29:27 +00:00
Duncan P. N. Exon Smith 48b3503c16 DebugInfo: Add missing !dbg attachments to intrinsics
Add missing `!dbg` attachments to `@llvm.dbg.*` intrinsics.  I updated
these using a script (add-dbg-to-intrinsics.sh) that I'll attach to
PR22778 for posterity.

llvm-svn: 235040
2015-04-15 21:04:10 +00:00
Rafael Espindola 10f3de6889 Update tests to not be as dependent on section numbers.
Many of these predate llvm-readobj. With elf-dump we had to match
a relocation to symbol number and symbol number to symbol name or
section number.

llvm-svn: 235015
2015-04-15 15:59:37 +00:00
Daniel Jasper a73f3d51ac Re-apply r234898 and fix tests.
This commit makes LLVM not estimate branch probabilities when doing a
single bit bitmask tests.

The code that originally made me discover this is:

  if ((a & 0x1) == 0x1) {
    ..
  }

In this case we don't actually have any branch probability information
and should not assume to have any. LLVM transforms this into:

  %and = and i32 %a, 1
  %tobool = icmp eq i32 %and, 0

So, in this case, the result of a bitwise and is compared against 0,
but nevertheless, we should not assume to have probability
information.

CodeGen/ARM/2013-10-11-select-stalls.ll started failing because the
changed probabilities changed the results of
ARMBaseInstrInfo::isProfitableToIfCvt() and led to an Ifcvt of the
diamond in the test. AFAICT, the test was never meant to test this and
thus changing the test input slightly to not change the probabilities
seems like the best way to preserve the meaning of the test.

llvm-svn: 234979
2015-04-15 06:24:07 +00:00
Krzysztof Parzyszek 3ff5657329 Remove this test until I figure out why it fails
llvm-svn: 234777
2015-04-13 18:57:50 +00:00
Krzysztof Parzyszek 13b4b013b5 Make the ARM testcase from r234764 also pass on Thumb
llvm-svn: 234772
2015-04-13 18:39:52 +00:00
Krzysztof Parzyszek a46c36b8f4 Allow memory intrinsics to be tail calls
llvm-svn: 234764
2015-04-13 17:16:45 +00:00
John Brawn e8fd6c8563 [ARM] Align global variables passed to memory intrinsics
Fill in the TODO in CodeGenPrepare::OptimizeCallInst so that global
variables that are passed to memory intrinsics are aligned in the same
way that allocas are.

Differential Revision: http://reviews.llvm.org/D8421

llvm-svn: 234735
2015-04-13 10:47:39 +00:00
Ahmed Bougacha b96444efd1 [CodeGen] Split -enable-global-merge into ARM and AArch64 options.
Currently, there's a single flag, checked by the pass itself.
It can't force-enable the pass (and is on by default), because it
might not even have been created, as that's the targets decision.
Instead, have separate explicit flags, so that the decision is
consistently made in the target.

Keep the flag as a last-resort "force-disable GlobalMerge" for now,
for backwards compatibility.

llvm-svn: 234666
2015-04-11 00:06:36 +00:00
Javed Absar 5c5e3c5e36 [ARM] support for Cortex-R4/R4F
Currently, llvm (backend) doesn't know cortex-r4, even though it is the
default target for armv7r. Using "--target=armv7r-arm-none-eabi" provokes
'cortex-r4' is not a recognized processor for this target' by llvm.
This patch adds support for cortex-r4 and, very closely related, r4f.

llvm-svn: 234486
2015-04-09 14:07:28 +00:00
Scott Douglass 7ad7792088 [ARM] make vminnm/vmaxnm work with ?le, ?ge and no-nans-fp-math
Because -menable-no-nans causes fcmp conditions to be rewritten
without 'o' or 'u' the recognition code in needs to cope. Also
extended it to handle 'le' and 'ge.

Differential Revision: http://reviews.llvm.org/D8725

llvm-svn: 234421
2015-04-08 17:18:28 +00:00
Sergey Dmitrouk 3cc62b3715 [ARM][Debug Info] Restore emitting of .cfi_def_cfa_offset for functions without stack frame
Summary: Looks like new code from [[ http://reviews.llvm.org/rL222057 | rL222057 ]] doesn't account for early `return` in `ARMFrameLowering::emitPrologue`, which leads to loosing `.cfi_def_cfa_offset` directive for functions without stack frame.

Reviewers: echristo, rengolin, asl, t.p.northover

Reviewed By: t.p.northover

Subscribers: llvm-commits, rengolin, aemerson

Differential Revision: http://reviews.llvm.org/D8606

llvm-svn: 234399
2015-04-08 10:10:12 +00:00
Duncan P. N. Exon Smith 81f522a62e Verifier: Check that inlined-at locations agree
Check that the `MDLocalVariable::getInlinedAt()` in a debug info
intrinsic's variable always matches the `MDLocation::getInlinedAt()` of
its `!dbg` attachment.

The goal here is to get rid of `MDLocalVariable::getInlinedAt()`
entirely (PR22778), since it's expensive and unnecessary, but I'll let
this verifier check bake for a while (a week maybe?) first.  I've
updated the testcases that had the wrong value for `inlinedAt:`.

This checks that things are sane in the IR, but currently things go out
of whack in a few places in the backend.  I'll follow shortly with
assertions in the backend (with code fixes).

If you have out-of-tree testcases that just started failing, here's how
I updated these ones:

 1. The verifier check gives you the basic block, function, instruction,
    and relevant metadata arguments (metadata numbering doesn't
    necessarily match the source file, unfortunately).
 2. Look at the `@llvm.dbg.*()` instruction, and compare the
    `inlinedAt:` fields of the variable argument (second `metadata`
    argument) and the `!dbg` attachment.
 3. Figure out based on the variable `scope:` chain and the functions in
    the file whether the variable has been inlined (and into what), so
    you can determine which `inlinedAt:` is actually correct.  In all of
    the in-tree testcases, the `!MDLocation()` was correct and the
    `!MDLocalVariable()` was wrong, but YMMV.
 4. Duplicate the metadata that you're going to change, and add/drop the
    `inlinedAt:` field from one of them.  Be careful that the other
    references to the same metadata node point at the correct one.

llvm-svn: 234021
2015-04-03 16:54:30 +00:00
Matthias Braun 6a42d7fd6b ARM: Handle physreg targets in RegPair hints gracefully
Register coalescing can change the target of a RegPair hint to a
physreg, we should not crash on this. This also slightly improved the
way ARMBaseRegisterInfo::updateRegAllocHint() works.

llvm-svn: 233987
2015-04-03 00:18:38 +00:00
James Molloy 4c1b746771 [SDAG] Move TRUNCATE splitting logic into a helper, and use
it more liberally.

SplitVecOp_TRUNCATE has logic for recursively splitting oversize vectors
that need more than one round of splitting to become legal. There are many
other ISD nodes that could benefit from this logic, so factor it out and
use it for FP_TO_UINT,FP_TO_SINT,SINT_TO_FP,UINT_TO_FP and FTRUNC.

llvm-svn: 233681
2015-03-31 10:20:58 +00:00
Akira Hatanaka ee97475b2e [ARM] Enable changing instprinter's behavior based on the per-function
subtarget.

llvm-svn: 233451
2015-03-27 23:41:42 +00:00
Duncan P. N. Exon Smith 988a7f8b79 DebugInfo: Fix bad debug info for compile units and types
Fix debug info in these tests, which started failing with a WIP patch to
verify compile units and types.  The problems look like they were all
caused by bitrot.  They fell into these categories:

  - Using `!{i32 0}` instead of `!{}`.
  - Using `!{null}` instead of `!{}`.
  - Using `!MDExpression()` instead of `!{}`.
  - Using `!8` instead of `!{!8}`.
  - `file:` references that pointed at `MDCompileUnit`s instead of the
    same `MDFile` as the compile unit.
  - `file:` references that were numerically off-by-one or (off-by-ten).

llvm-svn: 233415
2015-03-27 20:46:33 +00:00
Andrew Trick 43adfb30d5 Complete the MachineScheduler fix made way back in r210390.
"Fix the MachineScheduler's logic for updating ready times for in-order.
 Now the scheduler updates a node's ready time as soon as it is
 scheduled, before releasing dependent nodes."

This fix was only made in one variant of the ScheduleDAGMI driver.
Francois de Ferriere reported the issue in the other bit of code where
it was also needed.
I never got around to coming up with a test case, but it's an
obvious fix that shouldn't be delayed any longer.
I'll try to refactor this code a little better.

I did verify performance on a wide variety of targets and saw no
negative impact with this fix.

llvm-svn: 233366
2015-03-27 06:10:13 +00:00
Derek Schuff b051389f04 Use movw/movt instead of constant pool loads to lower byval parameter copies
Summary:
The ARM backend can use a loop to implement copying byval parameters before
a call. In non-thumb2 mode it uses a constant pool load to materialize the
trip count. For targets that need movt instead (e.g. Native Client), use
the same code as in thumb2 mode to materialize the trip count.

Reviewers: jfb, t.p.northover

Differential Revision: http://reviews.llvm.org/D8442

llvm-svn: 233324
2015-03-26 22:11:00 +00:00
Vladimir Sukharev 4b18c727a2 [ARM] Add v8.1a "Rounding Double Multiply Add/Subtract" extension
Reviewers: t.p.northover

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8503

llvm-svn: 233301
2015-03-26 18:29:02 +00:00
Vladimir Sukharev c632cda8b2 [AArch64, ARM] Add v8.1a architecture and generic cpu
New architecture and cpu added, following http://community.arm.com/groups/processors/blog/2014/12/02/the-armv8-a-architecture-and-its-ongoing-development

Reviewers: t.p.northover

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8505

llvm-svn: 233290
2015-03-26 17:05:54 +00:00
Ahmed Bougacha d1655cb1c0 [AArch64, ARM] Enable GlobalMerge with -O3 rather than -O1.
The pass used to be enabled by default with CodeGenOpt::Less (-O1).
This is too aggressive, considering the pass indiscriminately merges
all globals together.

Currently, performance doesn't always improve, and, on code that uses
few globals (e.g., the odd file- or function- static), more often than
not is degraded by the optimization.  Lengthy discussion can be found
on llvmdev (AArch64-focused;  ARM has similar problems):
  http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-February/082800.html
Also, it makes tooling and debuggers less useful when dealing with
globals and data sections.

GlobalMerge needs to better identify those cases that benefit, and this
will be done separately.  In the meantime, move the pass to run with
-O3 rather than -O1, on both ARM and AArch64.

llvm-svn: 233024
2015-03-23 21:17:36 +00:00
Bradley Smith ae0ad9c95d Revert "[ARM] Add more pattern matching for f16 <-> f64 conversions"
This change is incorrect since it converts double rounding into single rounding,
which can produce different results. Instead this optimization will be done by
modifying Clang's codegen to not produce double rounding in the first place.

This reverts commit r232954.

llvm-svn: 232962
2015-03-23 16:52:52 +00:00
Bradley Smith bc0f0d8c49 [ARM] Add more pattern matching for f16 <-> f64 conversions
Specifically when the conversion is done in two steps, f16 -> f32 -> f64.

For example:

%1 = tail call float @llvm.convert.from.fp16.f32(i16 %0)
%conv = fpext float %1 to double

to:

vcvtb.f64.f16

llvm-svn: 232954
2015-03-23 15:59:54 +00:00
Ahmed Bougacha 7173b669b4 [CodeGen][IfCvt] Don't re-ifcvt blocks with unanalyzable terminators.
If we couldn't analyze its terminator (i.e., it's an indirectbr, or some
other weirdness), we can't safely re-if-convert a predicated block,
because we can't tell whether the predicated terminator can
fallthrough (it does).

Currently, we would completely ignore the fallthrough successor. In
the added testcase, this means we used to generate:

    ...
  @ %entry:
    cmp   r5, #21
    ittt  ne
  @ %cc1f:
    cmpne r7, #42
  @ %cc2t:
    strne.w       r5, [r8]
    movne pc, r10
  @ %cc1t:
    ...

Whereas the successor of %cc1f was originally %bb1.
With the fix, we get the correct:

    ...
  @ %entry:
    cmp   r5, #21
    itt   eq
  @ %cc1t:
    streq.w       r5, [r11]
    moveq pc, r0
  @ %cc1f:
    cmp   r7, #42
    itt   ne
  @ %cc2t:
    strne.w       r5, [r8]
    movne pc, r10
  @ %bb1:
    ...

rdar://20192768
Differential Revision: http://reviews.llvm.org/D8509

llvm-svn: 232872
2015-03-21 01:23:15 +00:00
Rafael Espindola 36a15cb975 Don't declare all text sections at the start of the .s
The code this patch removes was there to make sure the text sections went
before the dwarf sections. That is necessary because MachO uses offsets
relative to the start of the file, so adding a section can change relaxations.

The dwarf sections were being printed at the start just to produce symbols
pointing at the start of those sections.

The underlying issue was fixed in r231898. The dwarf sections are now printed
when they are about to be used, which is after we printed the text sections.

To make sure we don't regress, the patch makes the MachO streamer assert
if CodeGen puts anything unexpected after the DWARF sections.

llvm-svn: 232842
2015-03-20 20:00:01 +00:00
Owen Anderson db4201235b Fix a nasty bug in DAGCombine of STORE nodes.
This is very related to the bug fixed in r174431.  The problem is that
SelectionDAG does not include alignment in the uniquing of loads and
stores.  When an otherwise no-op DAGCombine would increase the alignment
of a load or store, the original node would be returned (with the
alignment increased), which would cause the node not to be processed by
any further DAGCombines.

I don't have a direct testcase for this that manifests on an in-tree
target, but I did see some noise in the tests for other targets and have
updated them for it.

llvm-svn: 232780
2015-03-19 22:48:57 +00:00
John Brawn 0dbcd65442 [ARM] Align stack objects passed to memory intrinsics
Memcpy, and other memory intrinsics, typically tries to use LDM/STM if
the source and target addresses are 4-byte aligned. In CodeGenPrepare
look for calls to memory intrinsics and, if the object is on the
stack, 4-byte align it if it's large enough that we expect that memcpy
would want to use LDM/STM to copy it.

Differential Revision: http://reviews.llvm.org/D7908

llvm-svn: 232627
2015-03-18 12:01:59 +00:00
David Majnemer 7db449a6e7 COFF: Let globals with private linkage reside in their own section
COFF COMDATs (for selection kinds other than 'select any') require at
least one non-section symbol in the symbol table.
Satisfy this by morally enhancing the linkage from private to internal.

Differential Revision: http://reviews.llvm.org/D8394

llvm-svn: 232570
2015-03-17 23:54:51 +00:00
Richard Barton 30934c0926 [ARM] Fix offset calculation in ARMBaseRegisterInfo::needsFrameBaseReg
The input offset to needsFrameBaseReg is a negative value below the top of the
stack frame, but when converting to a positive offset from the bottom of the
stack frame this value was negated, causing the final offset to be too large
by twice the input offset's magnitude. Fix that by not negating the offset.

Patch by John Brawn

Differential Revision: http://reviews.llvm.org/D8316

llvm-svn: 232513
2015-03-17 18:20:47 +00:00
Rafael Espindola dc4263c760 Move the EH symbol to the asm printer and use it for the SJLJ case too.
llvm-svn: 232475
2015-03-17 13:57:48 +00:00
Renato Golin 1235060734 [ARM] Add support for ARMV6K subtarget (LLVM)
ARMv6K is another layer between ARMV6 and ARMV6T2. This is the LLVM
side of the changes.

ARMV6 family LLVM implementation.

+-------------------------------------+
| ARMV6                               |
+----------------+--------------------+
| ARMV6M (thumb) | ARMV6K (arm,thumb) | <- From ARMV6K and ARMV6M processors
+----------------+--------------------+    have support for hint instructions
| ARMV6T2 (arm,thumb,thumb2)          |    (SEV/WFE/WFI/NOP/YIELD). They can
+-------------------------------------+    be either real or default to NOP.
| ARMV7 (arm,thumb,thumb2)            |    The two processors also use
+-------------------------------------+    different encoding for them.

Patch by Vinicius Tinti.

llvm-svn: 232468
2015-03-17 11:55:28 +00:00
David Blaikie f72d05bc7b [opaque pointer type] Add textual IR support for explicit type parameter to gep operator
Similar to gep (r230786) and load (r230794) changes.

Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.

(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)

import fileinput
import sys
import re

rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)

def conv(match):
  line = match.group(1)
  line += match.group(4)
  line += ", "
  line += match.group(2)
  return line

line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
  sys.stdout.write(line[off:match.start()])
  sys.stdout.write(conv(match))
  off = match.end()
sys.stdout.write(line[off:])

llvm-svn: 232184
2015-03-13 18:20:45 +00:00
Tim Northover 8cda34f5e7 ARM: simplify and extend byval handling
The main issue being fixed here is that APCS targets handling a "byval align N"
parameter with N > 4 were miscounting what objects were where on the stack,
leading to FrameLowering setting the frame pointer incorrectly and clobbering
the stack.

But byval handling had grown over many years, and had multiple layers of cruft
trying to compensate for each other and calculate padding correctly. This only
really needs to be done once, in the HandleByVal function. Elsewhere should
just do what it's told by that call.

I also stripped out unnecessary APCS/AAPCS distinctions (now that Clang emits
byvals with the correct C ABI alignment), which simplified HandleByVal.

rdar://20095672

llvm-svn: 231959
2015-03-11 18:54:22 +00:00
Eric Christopher e035e26655 Remove use of misched-bench from this test and replace it with
non-temporary enabling options. This is part of removing misched-bench
as an option.

llvm-svn: 231546
2015-03-07 01:39:06 +00:00
Eric Christopher 7e70aba1a8 Recommit r231324 with a fix to the ARM execution domain code
to disable lane switching if we don't actually have the instruction
set we want to switch to. Models the earlier check above the
conditional for the pass.

The testcase is one that triggered with the assert that's added
as part of the fix, use it to avoid adding a new testcase as it
highlights the same problem.

llvm-svn: 231539
2015-03-07 00:12:22 +00:00
Matthias Braun 898d11e864 DAGCombiner: Canonicalize select(and/or,x,y) depending on target.
This is based on the following equivalences:
select(C0 & C1, X, Y) <=> select(C0, select(C1, X, Y), Y)
select(C0 | C1, X, Y) <=> select(C0, X, select(C1, X, Y))

Many target cannot perform and/or on the CPU flags and therefore the
right side should be choosen to avoid materializign the i1 flags in an
integer register. If the target can perform this operation efficiently
we normalize to the left form.

Differential Revision: http://reviews.llvm.org/D7622

llvm-svn: 231507
2015-03-06 19:49:10 +00:00
Ahmed Bougacha 4200cc95b4 [ARM] Enable vector extload combine for legal types.
This commit enables forming vector extloads for ARM.
It only does so for legal types, and when we can't fold the extension
in a wide/long form of the user instruction.

Enabling it for larger types isn't as good an idea on ARM as it is on
X86, because: 
- we pretend that extloads are legal, but end up generating vld+vmov
- we have instructions like vld {dN, dM}, which can't be generated
  when we "manually expand" extloads to vld+vmov.

For legal types, the combine doesn't fire that often: in the
integration tests only in a big endian testcase, where it removes a
pointless AND.

Related to rdar://19723053
Differential Revision: http://reviews.llvm.org/D7423

llvm-svn: 231396
2015-03-05 19:37:53 +00:00
Matthias Braun eca5151780 Improve test robustness
Improve test robustness in preparation of coming commits:
- Avoid undefs which may get propagated too much.
- Remove several pointless add 0, instructions

llvm-svn: 231307
2015-03-04 22:31:18 +00:00
Adrian Prantl afdac4b7f0 Update the out-of-date dwarf expressions in these testcases.
llvm-svn: 231261
2015-03-04 17:39:59 +00:00
Duncan P. N. Exon Smith e274180f0e DebugInfo: Move new hierarchy into place
Move the specialized metadata nodes for the new debug info hierarchy
into place, finishing off PR22464.  I've done bootstraps (and all that)
and I'm confident this commit is NFC as far as DWARF output is
concerned.  Let me know if I'm wrong :).

The code changes are fairly mechanical:

  - Bumped the "Debug Info Version".
  - `DIBuilder` now creates the appropriate subclass of `MDNode`.
  - Subclasses of DIDescriptor now expect to hold their "MD"
    counterparts (e.g., `DIBasicType` expects `MDBasicType`).
  - Deleted a ton of dead code in `AsmWriter.cpp` and `DebugInfo.cpp`
    for printing comments.
  - Big update to LangRef to describe the nodes in the new hierarchy.
    Feel free to make it better.

Testcase changes are enormous.  There's an accompanying clang commit on
its way.

If you have out-of-tree debug info testcases, I just broke your build.

  - `upgrade-specialized-nodes.sh` is attached to PR22564.  I used it to
    update all the IR testcases.
  - Unfortunately I failed to find way to script the updates to CHECK
    lines, so I updated all of these by hand.  This was fairly painful,
    since the old CHECKs are difficult to reason about.  That's one of
    the benefits of the new hierarchy.

This work isn't quite finished, BTW.  The `DIDescriptor` subclasses are
almost empty wrappers, but not quite: they still have loose casting
checks (see the `RETURN_FROM_RAW()` macro).  Once they're completely
gutted, I'll rename the "MD" classes to "DI" and kill the wrappers.  I
also expect to make a few schema changes now that it's easier to reason
about everything.

llvm-svn: 231082
2015-03-03 17:24:31 +00:00
Adrian Prantl 92da14b244 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

This reapplies 230930 without the assertion in DebugLocEntry::finalize()
because not all Machine registers can be lowered into DWARF register
numbers and floating point constants cannot be expressed.

llvm-svn: 231023
2015-03-02 22:02:33 +00:00
Adrian Prantl 2185aa179d Revert "Refactor DebugLocDWARFExpression so it doesn't require access to the"
This reverts commit 230975 to investigate buildbot breakage.

llvm-svn: 231004
2015-03-02 20:01:54 +00:00
Adrian Prantl d50bca7314 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

This reapplies 230930 with a relaxed assertion in DebugLocEntry::finalize()
that allows for empty DWARF expressions for constant FP values.

llvm-svn: 230975
2015-03-02 17:21:06 +00:00
Nico Weber 968ceddca9 Revert r230930, it caused PR22747.
llvm-svn: 230932
2015-03-02 04:37:11 +00:00
Adrian Prantl e2c9e64532 Refactor DebugLocDWARFExpression so it doesn't require access to the
TargetRegisterInfo. DebugLocEntry now holds a buffer with the raw bytes
of the pre-calculated DWARF expression.

Ought to be NFC, but it does slightly alter the output format of the
textual assembly.

llvm-svn: 230930
2015-03-02 02:38:18 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
David Blaikie 79e6c74981 [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction
One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
  handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
  in-memory representation will be in separate changes.

* geps of vectors are transformed as:
    getelementptr <4 x float*> %x, ...
  ->getelementptr float, <4 x float*> %x, ...
  Then, once the opaque pointer type is introduced, this will ultimately look
  like:
    getelementptr float, <4 x ptr> %x
  with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
    getelementptr float addrspace(1)* %x
  ->getelementptr float, float addrspace(1)* %x
  Then, eventually:
    getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile(       r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
  if not match:
    return line
  line = match.groups()[0]
  if len(match.groups()[5]) == 0:
    line += match.groups()[2]
  line += match.groups()[3]
  line += ", "
  line += match.groups()[1]
  line += "\n"
  return line

for line in sys.stdin:
  if line.find("getelementptr ") == line.find("getelementptr inbounds"):
    if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
      line = conv(re.match(ibrep, line), line)
  elif line.find("getelementptr ") != line.find("getelementptr ("):
    line = conv(re.match(normrep, line), line)
  sys.stdout.write(line)

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

llvm-svn: 230786
2015-02-27 19:29:02 +00:00
Mehdi Amini 945a660cbc Change the fast-isel-abort option from bool to int to enable "levels"
Summary:
Currently fast-isel-abort will only abort for regular instructions,
and just warn for function calls, terminators, function arguments.
There is already fast-isel-abort-args but nothing for calls and
terminators.

This change turns the fast-isel-abort options into an integer option,
so that multiple levels of strictness can be defined.
This will help no being surprised when the "abort" option indeed does
not abort, and enables the possibility to write test that verifies
that no intrinsics are forgotten by fast-isel.

Reviewers: resistor, echristo

Subscribers: jfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D7941

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 230775
2015-02-27 18:32:11 +00:00
Renato Golin a78995c0a0 Equally to NetBSD, Bitrig/ARM uses the Itanium-ABI.
Patch by Patrick Wildt.

llvm-svn: 230762
2015-02-27 16:35:27 +00:00
Petar Jovanovic 1df918083c Pass correct -mtriple for krait-cpu-div-attribute.ll
Not passing mtriple for one of the tests caused a regression failure
on MIPS buildbot. The issue was introduced by r230651.

Differential Revision: http://reviews.llvm.org/D7938

llvm-svn: 230756
2015-02-27 14:46:41 +00:00
Sumanth Gundapaneni 28a3b86b06 Use ".arch_extension" ARM directive to support hwdiv on krait
In case of "krait" CPU, asm printer doesn't emit any ".cpu" so the
features bits are not computed. This patch lets the asm printer
emit ".cpu cortex-a9" directive for krait and the hwdiv feature is
enabled through ".arch_extension". In short, krait is treated
as "cortex-a9" with hwdiv. We can not emit ".krait" as CPU since
it is not supported bu GNU GAS yet

llvm-svn: 230651
2015-02-26 18:08:41 +00:00
Renato Golin b9887ef32a Improve handling of stack accesses in Thumb-1
Thumb-1 only allows SP-based LDR and STR to be word-sized, and SP-base LDR,
STR, and ADD only allow offsets that are a multiple of 4. Make some changes
to better make use of these instructions:

* Use word loads for anyext byte and halfword loads from the stack.
* Enforce 4-byte alignment on objects accessed in this way, to ensure that
  the offset is valid.
* Do the same for objects whose frame index is used, in order to avoid having
  to use more than one ADD to generate the frame index.
* Correct how many bits of offset we think AddrModeT1_s has.

Patch by John Brawn.

llvm-svn: 230496
2015-02-25 14:41:06 +00:00
Simon Pilgrim b1468daf00 Added test case for PR22678 (check CONCAT_VECTORS DAG combiner pass doesn't introduce illegal types)
llvm-svn: 230386
2015-02-24 21:46:23 +00:00
Tim Northover e95c5b3236 ARM: treat [N x i32] and [N x i64] as AAPCS composite types
The logic is almost there already, with our special homogeneous aggregate
handling. Tweaking it like this allows front-ends to emit AAPCS compliant code
without ever having to count registers or add discarded padding arguments.

Only arrays of i32 and i64 are needed to model AAPCS rules, but I decided to
apply the logic to all integer arrays for more consistency.

llvm-svn: 230348
2015-02-24 17:22:34 +00:00
Ahmed Bougacha db141ac37d [ARM] Re-re-apply VLD1/VST1 base-update combine.
This re-applies r223862, r224198, r224203, and r224754, which were
reverted in r228129 because they exposed Clang misalignment problems
when self-hosting.

The combine caused the crashes because we turned ISD::LOAD/STORE nodes
to ARMISD::VLD1/VST1_UPD nodes.  When selecting addressing modes, we
were very lax for the former, and only emitted the alignment operand
(as in "[r1:128]") when it was larger than the standard alignment of
the memory type.

However, for ARMISD nodes, we just used the MMO alignment, no matter
what.  In our case, we turned ISD nodes to ARMISD nodes, and this
caused the alignment operands to start being emitted.

And that's how we exposed alignment problems that were ignored before
(but I believe would have been caught with SCTRL.A==1?).

To fix this, we can just mirror the hack done for ISD nodes:  only
take into account the MMO alignment when the access is overaligned.

Original commit message:
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.

We can do the same thing for generic load/stores.

Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).

rdar://19717869, rdar://14062261.

llvm-svn: 229932
2015-02-19 23:52:41 +00:00
Peter Collingbourne f4498a4fd3 llvm-mc: Use Target::createNullStreamer to fix crashes on target-specific asm directives.
llvm-svn: 229798
2015-02-19 00:45:04 +00:00
Bradley Smith 26c9922a59 [ARM] Add missing M/R class CPUs
Add some of the missing M and R class Cortex CPUs, namely:

Cortex-M0+ (called Cortex-M0plus for GCC compatibility)
Cortex-M1
SC000
SC300
Cortex-R5

llvm-svn: 229660
2015-02-18 10:33:30 +00:00
Sanjay Patel ab7e86e5be Canonicalize splats as build_vectors (PR22283)
This is a follow-on patch to:
http://reviews.llvm.org/D7093

That patch canonicalized constant splats as build_vectors, 
and this patch removes the constant check so we can canonicalize
all splats as build_vectors.

This fixes the 2nd test case in PR22283:
http://llvm.org/bugs/show_bug.cgi?id=22283

The unfortunate code duplication between SelectionDAG and DAGCombiner
is discussed in the earlier patch review. At least this patch is just
removing code...

This improves an existing x86 AVX test and changes codegen in an ARM test.

Differential Revision: http://reviews.llvm.org/D7389

llvm-svn: 229511
2015-02-17 16:54:32 +00:00
James Molloy 7c336576a5 [SimplifyCFG] Swap to using TargetTransformInfo for cost
analysis.

We're already using TTI in SimplifyCFG, so remove the hard-baked "cheapness"
heuristic and use TTI directly. Generally NFC intended, but we're using a slightly
different heuristic now so there is a slight test churn.

Test changes:
  * combine-comparisons-by-cse.ll: Removed unneeded branch check.
  * 2014-08-04-muls-it.ll: Test now doesn't branch but emits muleq.
  * coalesce-subregs.ll: Superfluous block check.
  * 2008-01-02-hoist-fp-add.ll: fadd is safe to speculate. Change to udiv.
  * PhiBlockMerge.ll: Superfluous CFG checking code. Main checks still present.
  * select-gep.ll: A variable GEP is not expensive, just TCC_Basic, according to the TTI.

llvm-svn: 228826
2015-02-11 12:15:41 +00:00
Bradley Smith e997b45076 [ARM] Add armv6s[-]m as an alias to armv6[-]m
llvm-svn: 228696
2015-02-10 15:15:08 +00:00
Akira Hatanaka 8d3cb829ce Fix a bug in DemoteRegToStack where a reload instruction was inserted into the
wrong basic block.

This would happen when the result of an invoke was used by a phi instruction
in the invoke's normal destination block. An instruction to reload the invoke's
value would get inserted before the critical edge was split and a new basic
block (which is the correct insertion point for the reload) was created. This
commit fixes the bug by splitting the critical edge before all the reload
instructions are inserted.

Also, hoist up the code which computes the insertion point to the only place
that need that computation.

rdar://problem/15978721

llvm-svn: 228566
2015-02-09 06:38:23 +00:00
Tim Northover 45aa89c925 ARM & AArch64: teach LowerVSETCC that output type size may differ from input.
While various DAG combines try to guarantee that a vector SETCC
operation will have the same output size as input, there's nothing
intrinsic to either creation or LegalizeTypes that actually guarantees
it, so the function needs to be ready to handle a mismatch.

Fortunately this is easy enough, just extend or truncate the naturally
compared result.

I couldn't reproduce the failure in other backends that I know have
SIMD, so it's probably only an issue for these two due to shared
heritage.

Should fix PR21645.

llvm-svn: 228518
2015-02-08 00:50:47 +00:00
David Majnemer 5614ea9aae MC: Emit COFF section flags in the "proper" order
COFF section flags are not idempotent:
  'rd' will make a read-write section because 'd' implies write
  'dr' will make a read-only section because 'r' disables write

llvm-svn: 228490
2015-02-07 08:26:40 +00:00
Ahmed Bougacha c7f241cba9 [ARM] Use patterns instead of hardcoded regs in test. NFC.
llvm-svn: 228259
2015-02-05 01:52:19 +00:00
Ahmed Bougacha daaf3d9b58 [ARM] Make testcase more explicit. NFC.
The q8/d16 thing is silly;  I'd be happy to hear about a better
way to write those tests where simple substitution isn't enough..

llvm-svn: 228258
2015-02-05 01:45:28 +00:00
Renato Golin 6088504499 Adding support to LLVM for targeting Cortex-A72
Currently, Cortex-A72 is modelled as an Cortex-A57 except the fp
load balancing pass isn't enabled for Cortex-A72 as it's not
profitable to have it enabled for this core.

Patch by Ranjeet Singh.

llvm-svn: 228140
2015-02-04 13:31:29 +00:00
Renato Golin 2a5c0a51ce Reverting VLD1/VST1 base-updating/post-incrementing combining
This reverts patches 223862, 224198, 224203, and 224754, which were all
related to the vector load/store combining and were reverted/reaplied
a few times due to the same alignment problems we're seeing now.

Further tests, mainly self-hosting Clang, will be needed to reapply this
patch in the future.

llvm-svn: 228129
2015-02-04 10:11:59 +00:00
Jan Wen Voung d21194f712 Fix ARM peephole optimizeCompare to avoid optimizing unsigned cmp to 0.
Summary:
Previously it only avoided optimizing signed comparisons to 0.
Sometimes the DAGCombiner will optimize the unsigned comparisons
to 0 before it gets to the peephole pass, but sometimes it doesn't.

Fix for PR22373.

Test Plan: test/CodeGen/ARM/sub-cmp-peephole.ll

Reviewers: jfb, manmanren

Subscribers: aemerson, llvm-commits

Differential Revision: http://reviews.llvm.org/D7274

llvm-svn: 227809
2015-02-02 16:56:50 +00:00
Saleem Abdulrasool fb8a66fbc5 ARM: support stack probe size on Windows on ARM
Now that -mstack-probe-size is piped through to the backend via the function
attribute as on Windows x86, honour the value to permit handling of non-default
values for stack probes.  This is needed /Gs with the clang-cl driver or
-mstack-probe-size with the clang driver when targeting Windows on ARM.

llvm-svn: 227667
2015-01-31 02:26:37 +00:00
Charlie Turner ed76a05c4d Add a missing Tag_DIV_use test for Cortex-M7.
llvm-svn: 227429
2015-01-29 11:19:54 +00:00
Jyoti Allur f1d7050a25 This patch fixes issue with lowering below mentioned pattern :-
_foo:
        smull	 r0, r1, r1, r0
	smull	 r2, r3, r3, r2
	adds	r0, r2, r0
	adc	r1, r3, r1
	bx	lr

to

_foo:
        smull	 r0, r1, r1, r0
	smlal	 r0, r1, r3, r2
	bx	lr

llvm-svn: 226904
2015-01-23 09:10:03 +00:00
Jonathan Roelofs 229eb4ca5c Fix load-store optimizer on thumbv4t
Thumbv4t does not have lo->lo copies other than MOVS,
and that can't be predicated. So emit MOVS when needed
and bail if there's a predicate.

http://reviews.llvm.org/D6592

llvm-svn: 226711
2015-01-21 22:39:43 +00:00
Rafael Espindola 12ca34f53f Bring r226038 back.
No change in this commit, but clang was changed to also produce trivial comdats when
needed.

Original message:

Don't create new comdats in CodeGen.

This patch stops the implicit creation of comdats during codegen.

Clang now sets the comdat explicitly when it is required. With this patch clang and gcc
now produce the same result in pr19848.

llvm-svn: 226467
2015-01-19 15:16:06 +00:00
Timur Iskhodzhanov 60b721363c Revert r226242 - Revert Revert Don't create new comdats in CodeGen
This breaks AddressSanitizer (ninja check-asan) on Windows

llvm-svn: 226251
2015-01-16 08:38:45 +00:00
Rafael Espindola 67a79e72f5 Revert "Revert Don't create new comdats in CodeGen"
This reverts commit r226173, adding r226038 back.

No change in this commit, but clang was changed to also produce trivial comdats for
costructors, destructors and vtables when needed.

Original message:

Don't create new comdats in CodeGen.

This patch stops the implicit creation of comdats during codegen.

Clang now sets the comdat explicitly when it is required. With this patch clang and gcc
now produce the same result in pr19848.

llvm-svn: 226242
2015-01-16 02:22:55 +00:00
Hal Finkel 5ef58eb86d Revert "r226086 - Revert "r226071 - [RegisterCoalescer] Remove copies to reserved registers""
Reapply r226071 with fixes. Two fixes:

 1. We need to manually remove the old and create the new 'deaf defs'
    associated with physical register definitions when we move the definition of
    the physical register from the copy point to the point of the original vreg def.

    This problem was picked up by the machinstr verifier, and could trigger a
    verification failure on test/CodeGen/X86/2009-02-12-DebugInfoVLA.ll, so I've
    turned on the verifier in the tests.

 2. When moving the def point of the phys reg up, we need to make sure that it
    is neither defined nor read in between the two instructions. We don't, however,
    extend the live ranges of phys reg defs to cover uses, so just checking for
    live-range overlap between the pair interval and the phys reg aliases won't
    pick up reads. As a result, we manually iterate over the range and check for
    reads.

    A test soon to be committed to the PowerPC backend will test this change.

Original commit message:

[RegisterCoalescer] Remove copies to reserved registers

This allows the RegisterCoalescer to join "non-flipped" range pairs with a
physical destination register -- which allows the RegisterCoalescer to remove
copies like this:

<vreg> = something (maybe a load, for example)
... (things that don't use PHYSREG)
PHYSREG = COPY <vreg>

(with all of the restrictions normally applied by the RegisterCoalescer: having
compatible register classes, etc. )

Previously, the RegisterCoalescer handled only the opposite case (copying
*from* a physical register). I don't handle the problem fully here, but try to
get the common case where there is only one use of <vreg> (the COPY).

An upcoming commit to the PowerPC backend will make this pattern much more
common on PPC64/ELF systems.

llvm-svn: 226200
2015-01-15 20:32:09 +00:00
Timur Iskhodzhanov f5adf13fac Revert Don't create new comdats in CodeGen
It breaks AddressSanitizer on Windows.

llvm-svn: 226173
2015-01-15 16:14:34 +00:00
Hal Finkel dd669615dd Revert "r226071 - [RegisterCoalescer] Remove copies to reserved registers"
Reverting this while I investigate some bad behavior this is causing. As a
possibly-related issue, adding -verify-machineinstrs to one of the test cases
now fails because of this change:

  llc test/CodeGen/X86/2009-02-12-DebugInfoVLA.ll -march=x86-64 -o - -verify-machineinstrs

*** Bad machine code: No instruction at def index ***
- function:    foo
- basic block: BB#0 return (0x10007e21f10) [0B;736B)
- liverange:   [128r,128d:9)[160r,160d:8)[176r,176d:7)[336r,336d:6)[464r,464d:5)[480r,480d:4)[624r,624d:3)[752r,752d:2)[768r,768d:1)[78
4r,784d:0)  0@784r 1@768r 2@752r 3@624r 4@480r 5@464r 6@336r 7@176r 8@160r 9@128r
- register:    %DS
Valno #3 is defined at 624r

*** Bad machine code: Live segment doesn't end at a valid instruction ***
- function:    foo
- basic block: BB#0 return (0x10007e21f10) [0B;736B)
- liverange:   [128r,128d:9)[160r,160d:8)[176r,176d:7)[336r,336d:6)[464r,464d:5)[480r,480d:4)[624r,624d:3)[752r,752d:2)[768r,768d:1)[78
4r,784d:0)  0@784r 1@768r 2@752r 3@624r 4@480r 5@464r 6@336r 7@176r 8@160r 9@128r
- register:    %DS
[624r,624d:3)
LLVM ERROR: Found 2 machine code errors.

where 624r corresponds exactly to the interval combining change:

624B    %RSP<def> = COPY %vreg16; GR64:%vreg16
        Considering merging %vreg16 with %RSP
                RHS = %vreg16 [608r,624r:0)  0@608r
                updated: 608B   %RSP<def> = MOV64rm <fi#3>, 1, %noreg, 0, %noreg; mem:LD8[%saved_stack.1]
        Success: %vreg16 -> %RSP
        Result = %RSP

llvm-svn: 226086
2015-01-15 03:08:59 +00:00
Hal Finkel 8299646236 [RegisterCoalescer] Remove copies to reserved registers
This allows the RegisterCoalescer to join "non-flipped" range pairs with a
physical destination register -- which allows the RegisterCoalescer to remove
copies like this:

<vreg> = something (maybe a load, for example)
... (things that don't use PHYSREG)
PHYSREG = COPY <vreg>

(with all of the restrictions normally applied by the RegisterCoalescer: having
compatible register classes, etc. )

Previously, the RegisterCoalescer handled only the opposite case (copying
*from* a physical register). I don't handle the problem fully here, but try to
get the common case where there is only one use of <vreg> (the COPY).

An upcoming commit to the PowerPC backend will make this pattern much more
common on PPC64/ELF systems.

llvm-svn: 226071
2015-01-15 01:25:28 +00:00
Duncan P. N. Exon Smith 9885469922 IR: Move MDLocation into place
This commit moves `MDLocation`, finishing off PR21433.  There's an
accompanying clang commit for frontend testcases.  I'll attach the
testcase upgrade script I used to PR21433 to help out-of-tree
frontends/backends.

This changes the schema for `DebugLoc` and `DILocation` from:

    !{i32 3, i32 7, !7, !8}

to:

    !MDLocation(line: 3, column: 7, scope: !7, inlinedAt: !8)

Note that empty fields (line/column: 0 and inlinedAt: null) don't get
printed by the assembly writer.

llvm-svn: 226048
2015-01-14 22:27:36 +00:00
Rafael Espindola fad1639a12 Don't create new comdats in CodeGen.
This patch stops the implicit creation of comdats during codegen.

Clang now sets the comdat explicitly when it is required. With this patch clang and gcc
now produce the same result in pr19848.

llvm-svn: 226038
2015-01-14 20:55:48 +00:00
Tim Northover a203ca61af ARM: add test for crc32 instructions in CodeGen.
Somehow we seem to have ended up without any actual tests of the
CodeGen side. Easy enough to fix.

llvm-svn: 225930
2015-01-14 01:43:33 +00:00
Adrian Prantl b16d9ebb0c Debug info: Factor out the creation of DWARF expressions from AsmPrinter
into a new class DwarfExpression that can be shared between AsmPrinter
and DwarfUnit.

This is the first step towards unifying the two entirely redundant
implementations of dwarf expression emission in DwarfUnit and AsmPrinter.

Almost no functional change — Testcases were updated because asm comments
that used to be on two lines now appear on the same line, which is
actually preferable.

llvm-svn: 225706
2015-01-12 22:19:22 +00:00
Kristof Beyls 933de7aa06 Fix large stack alignment codegen for ARM and Thumb2 targets
This partially fixes PR13007 (ARM CodeGen fails with large stack
alignment): for ARM and Thumb2 targets, but not for Thumb1, as it
seems stack alignment for Thumb1 targets hasn't been supported at
all.

Producing an aligned stack pointer is done by zero-ing out the lower
bits of the stack pointer. The BIC instruction was used for this.
However, the immediate field of the BIC instruction only allows to
encode an immediate that can zero out up to a maximum of the 8 lower
bits. When a larger alignment is requested, a BIC instruction cannot
be used; llvm was silently producing incorrect code in this case.

This commit fixes code generation for large stack aligments by
using the BFC instruction instead, when the BFC instruction is
available.  When not, it uses 2 instructions: a right shift,
followed by a left shift to zero out the lower bits.

The lowering of ARM::Int_eh_sjlj_dispatchsetup still has code
that unconditionally uses BIC to realign the stack pointer, so it
very likely has the same problem. However, I wasn't able to
produce a test case for that. This commit adds an assert so that
the compiler will fail the assert instead of silently generating
wrong code if this is ever reached.

llvm-svn: 225446
2015-01-08 15:09:14 +00:00
Charlie Turner 06f22f4678 [ARM] Add missing Tag_DIV_use tests.
llvm-svn: 225348
2015-01-07 11:37:40 +00:00
Charlie Turner 8b2caa458f Emit the build attribute Tag_conformance.
Claim conformance to version 2.09 of the ARM ABI.

This build attribute must be emitted first amongst the build attributes when
written to an object file. This is to simplify conformance detection by
consumers.

Change-Id: If9eddcfc416bc9ad6e5cc8cdcb05d0031af7657e
llvm-svn: 225166
2015-01-05 13:12:17 +00:00
Saleem Abdulrasool 67f729933f ARM: permit tail calls to weak externals on COFF
Weak externals are resolved statically, so we can actually generate the tail
call on PE/COFF targets without breaking the requirements.  It is questionable
whether we want to propagate the current behaviour for MachO as the requirements
are part of the ARM ELF specifications, and it seems that prior to the SVN
r215890, we would have tail'ed the call.  For now, be conservative and only
permit it on PE/COFF where the call will always be fully resolved.

llvm-svn: 225119
2015-01-03 21:35:00 +00:00
Ahmed Bougacha 4553bff412 [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.

Differential Revision: http://reviews.llvm.org/D6759

llvm-svn: 224754
2014-12-23 06:07:31 +00:00
Rafael Espindola 2645d33977 Convert a few tests to FileCheck. NFC.
llvm-svn: 224705
2014-12-22 13:29:46 +00:00
Eric Christopher 661f2d1ca1 Add a new string member to the TargetOptions struct for the name
of the abi we should be using. For targets that don't use the
option there's no change, otherwise this allows external users
to set the ABI via string and avoid some of the -backend-option
pain in clang.

Use this option to move the ABI for the ARM port from the
Subtarget to the TargetMachine and update the testcases
accordingly since it's no longer valid to set via -mattr.

llvm-svn: 224492
2014-12-18 02:20:58 +00:00
Eric Christopher 1971c3508a Model ARM backend ABI selection after the front end code doing the
same. This will change the "bare metal" ABI from APCS to AAPCS.

The only difference between the front and back end code is that
the code for Triple::GNU was added for environment. That will migrate
to the front end shortly.

Tests updated with the ABI they were originally testing in the case
of bare metal (e.g. -mtriple armv7) or with a -gnu for arm-linux
triples.

llvm-svn: 224489
2014-12-18 02:08:45 +00:00
Bradley Smith ececb7f6e2 [ARM] Prevent PerformVCVTCombine from combining a vmul/vcvt with 8 lanes
This would result in a crash since the vcvt used does not support v8i32 types.

llvm-svn: 224332
2014-12-16 10:59:27 +00:00
Duncan P. N. Exon Smith be7ea19b58 IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

llvm-svn: 224257
2014-12-15 19:07:53 +00:00
Ahmed Bougacha 0cb861634b Reapply "[ARM] Combine base-updating/post-incrementing vector load/stores."
r223862 tried to also combine base-updating load/stores.
r224198 reverted it, as "it created a regression on the test-suite
on test MultiSource/Benchmarks/Ptrdist/anagram by scrambling the order
in which the words are shown."
Reapply, with a fix to ignore non-normal load/stores.
Truncstores are handled elsewhere (you can actually write a pattern for
those, whereas for postinc loads you can't, since they return two values),
but it should be possible to also combine extloads base updates, by checking
that the memory (rather than result) type is of the same size as the addend.

Original commit message:
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.

We can do the same thing for generic load/stores.

Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).

Differential Revision: http://reviews.llvm.org/D6585

llvm-svn: 224203
2014-12-13 23:22:12 +00:00
Renato Golin df8f9b6dc9 Revert "[ARM] Combine base-updating/post-incrementing vector load/stores."
This reverts commit r223862, as it created a regression on the test-suite
on test MultiSource/Benchmarks/Ptrdist/anagram by scrambling the order
in which the words are shown. We'll investigate the issue and re-apply
when safe.

llvm-svn: 224198
2014-12-13 20:23:18 +00:00
Charlie Turner 1a53996c31 Emit Tag_ABI_FP_16bit_format build attribute.
The __fp16 type is unconditionally exposed. Since -mfp16-format is not yet
supported, there is not a user switch to change this behaviour. This build
attribute should capture the default behaviour of the compiler, which is to
expose the IEEE 754 version of __fp16.

When -mfp16-format is emitted, that will be the way to control the value of
this build attribute.

Change-Id: I8a46641ff0fd2ef8ad0af5f482a6d1af2ac3f6b0
llvm-svn: 224115
2014-12-12 11:59:18 +00:00
Tim Northover 2ac7e4b3ee ARM: correctly expand LDR-lit based globals.
Quite a major error here: the expansions for the Pseudos with and without
folded load were mixed up. Fortunately it only affects ARM-mode, when not using
movw/movt, on Darwin. I'm guessing no-one actually uses that combination.

llvm-svn: 223986
2014-12-10 23:40:50 +00:00
Ahmed Bougacha 7efbac74ec [ARM] Combine base-updating/post-incrementing vector load/stores.
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.

We can do the same thing for generic load/stores.

Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).

Differential Revision: http://reviews.llvm.org/D6585

llvm-svn: 223862
2014-12-10 00:07:37 +00:00
Ahmed Bougacha 9d2d7c1b00 [ARM] Make testcase more explicit. NFC.
llvm-svn: 223841
2014-12-09 22:08:57 +00:00
Ahmed Bougacha be0b227679 [ARM] Also support v2f64 vld1/vst1.
It was missing from the VLD1/VST1 handling logic, even though the
corresponding instructions exist (same form as v2i64).

In preparation for a future patch.

llvm-svn: 223832
2014-12-09 21:25:00 +00:00
Charlie Turner c96e95c157 Add missing FP build attribute tests.
The test file test/CodeGen/ARM/build-attributes.ll was missing several
floating-point build attribute tests. The intention of this commit is that for
each CPU / architecture currently tested, there are now tests that make sure
the following attributes are sufficiently checked,

  * Tag_ABI_FP_rounding
  * Tag_ABI_FP_denormal
  * Tag_ABI_FP_exceptions
  * Tag_ABI_FP_user_exceptions
  * Tag_ABI_FP_number_model

Also in this commit, the -unsafe-fp-math flag has been augmented with the full
suite of flags Clang sends to LLVM when you pass -ffast-math to Clang. That is,
`-unsafe-fp-math' has been changed to `-enable-unsafe-fp-math -disable-fp-elim
-enable-no-infs-fp-math -enable-no-nans-fp-math -fp-contract=fast'

Change-Id: I35d766076bcbbf09021021c0a534bf8bf9a32dfc
llvm-svn: 223454
2014-12-05 08:22:47 +00:00
Jonathan Roelofs 300d8ffdf2 Fix thumbv4t indirect calls
So there are a couple of issues with indirect calls on thumbv4t. First, the most
'obvious' instruction, 'blx' isn't available until v5t. And secondly, the
next-most-obvious sequence: 'mov lr, pc; bx rN' doesn't DTRT in thumb code
because the saved off pc has its thumb bit cleared, so when the callee returns
we end up in ARM mode.... yuck.

The solution is to 'bl' to a nearby landing pad with a 'bx rN' in it.

We could cut down on code size by sharing the landing pads between call sites
that are close enough, but for the moment let's do correctness first and look at
performance later.


Patch by: Iain Sandoe

http://reviews.llvm.org/D6519

llvm-svn: 223380
2014-12-04 19:34:50 +00:00
Charlie Turner f02c92489a Emit ABI_FP_rounding attribute.
LLVM understands a -enable-sign-dependent-rounding-fp-math codegen option. When
the user has specified this option, the Tag_ABI_FP_rounding attribute should be
emitted with value 1. This option currently does not appear to disable
transformations and optimizations that assume default floating point rounding
behavior, AFAICT, but the intention should be recorded in the build attributes,
regardless of what the compiler actually does with the intention.

Change-Id: If838578df3dc652b6f2796b8d152545674bcb30e
llvm-svn: 223218
2014-12-03 08:12:26 +00:00
Charlie Turner 1620a69fe8 Add tests for default value of Tag_ABI_FP_rounding.
Change-Id: I051866d073fc6ce87ce3e693a3762da6d81f4393
llvm-svn: 223217
2014-12-03 07:59:50 +00:00
Charlie Turner 15f91c5240 Emit Tag_ABI_FP_denormal correctly in fast-math mode.
The default ARM floating-point mode does not support IEEE 754 mode exactly. Of
relevance to this patch is that input denormals are flushed to zero. The way in
which they're flushed to zero depends on the architecture,

  * For VFPv2, it is implementation defined as to whether the sign of zero is
    preserved.
  * For VFPv3 and above, the sign of zero is always preserved when a denormal
    is flushed to zero.

When FP support has been disabled, the strategy taken by this patch is to
assume the software support will mirror the behaviour of the hardware support
for the target *if it existed*. That is, for architectures which can only have
VFPv2, it is assumed the software will flush to positive zero. For later
architectures it is assumed the software will flush to zero preserving sign.

Change-Id: Icc5928633ba222a4ba3ca8c0df44a440445865fd
llvm-svn: 223110
2014-12-02 08:22:29 +00:00
Reid Kleckner 35fc363ce8 Parse 'ghccc' in .ll files as the GHC convention (cc 10)
Previously we just used "cc 10" in the .ll files, but that isn't very
human readable.

llvm-svn: 223076
2014-12-01 21:04:44 +00:00
Tim Northover 3024b5535c ARM: lower tail calls correctly when using GHC calling convention.
Patch by Ben Gamari.

llvm-svn: 223055
2014-12-01 17:46:39 +00:00
Charlie Turner 8d43369163 Stop uppercasing build attribute data.
The string data for string-valued build attributes were being unconditionally
uppercased. There is no mention in the ARM ABI addenda about case conventions,
so it's technically implementation defined as to whether the data are
capitialised in some way or not. However, there are good reasons not to
captialise the data.

  * It's less work.
  * Some vendors may legitimately have case-sensitive checks for these
    attributes which would fail on LLVM generated object files.
  * There could be locale issues with uppercasing.

The original reasons for uppercasing appear to have stemmed from an
old codesourcery toolchain behaviour, see

http://comments.gmane.org/gmane.comp.compilers.llvm.cvs/87133

This patch makes the object file emitted no longer captialise string
data, it encodes as seen in the assembly source.

Change-Id: Ibe20dd6e60d2773d57ff72a78470839033aa5538
llvm-svn: 222882
2014-11-27 12:13:56 +00:00
Renato Golin 609bf92365 Fix ARM triple parsing
The triple parser should only accept existing architecture names
when the triple starts with armv, armebv, thumbv or thumbebv.

Patch by Gabor Ballabas.

llvm-svn: 222129
2014-11-17 14:08:57 +00:00
Oliver Stannard 970b0d576c [Thumb1] Re-write emitThumbRegPlusImmediate
This was motivated by a bug which caused code like this to be
miscompiled:
  declare void @take_ptr(i8*)
  define void @test() {
    %addr1.32 = alloca i8
    %addr2.32 = alloca i32, i32 1028
    call void @take_ptr(i8* %addr1)
    ret void
  }

This was emitting the following assembly to get the value of %addr1:
  add r0, sp, #1020
  add r0, r0, #8
However, "add r0, r0, #8" is not a valid Thumb1 instruction, and this
could not be assembled. The generated object file contained this,
resulting in r0 holding SP+8 rather tha SP+1028:
  add r0, sp, #1020
  add r0, sp, #8

This function looked like it could have caused miscompilations for
other combinations of registers and offsets (though I don't think it is
currently called with these), and the heuristic it used did not match
the emitted code in all cases.

llvm-svn: 222125
2014-11-17 11:18:10 +00:00
Oliver Stannard d29db9b949 Fix optimisations of SELECT_CC which assumed result is boolean
Some optimisations in DAGCombiner cause miscompilations for targets that use
TargetLowering::UndefinedBooleanContent, because they assume that the results
of a SELECT_CC node are boolean values, and can be safely ANDed, ORed and
XORed. These optimisations are only valid for targets that use
ZeroOrOneBooleanContent or ZeroOrNegativeOneBooleanContent.

This is a follow-up to D6210/r221693.

llvm-svn: 222123
2014-11-17 10:49:31 +00:00
Tim Northover 603d316517 ARM: refactor .cfi_def_cfa_offset emission.
We use to track quite a few "adjusted" offsets through the FrameLowering code
to account for changes in the prologue instructions as we went and allow the
emission of correct CFA annotations. However, we were missing a couple of cases
and the code was almost impenetrable.

It's easier to just add any stack-adjusting instruction to a list and emit them
together.

llvm-svn: 222057
2014-11-14 22:45:33 +00:00
Tim Northover 9d2d218f49 ARM: correctly calculate the offset of FP in its push.
When we folded the DPR alignment gap into a push, we weren't noting the extra
distance from the beginning of the push to the FP, and so FP ended up pointing
at an incorrect offset.

The .cfi_def_cfa_offset directives are still wrong in this case, but I think
that can be improved by refactoring.

llvm-svn: 222056
2014-11-14 22:45:31 +00:00
Tim Northover a0691c8983 ARM: simplify test.
The test's DWARF stubs were there just to trigger the emission of .cfi
directives. Fortunately, the NetBSD ABI already demands proper DWARF unwind
info, so it's easier to just use that triple.

llvm-svn: 222055
2014-11-14 22:45:23 +00:00
Tim Northover ab85dcc7b8 ARM: avoid duplicating branches during constant islands.
We were using a naive heuristic to determine whether a basic block already had
an unconditional branch at the end. This mostly corresponded to reality
(assuming branches got optimised) because there's not much point in a branch to
the next block, but could go wrong.

llvm-svn: 221904
2014-11-13 17:58:51 +00:00
Tim Northover 650b0ee53b ARM: add @llvm.arm.space intrinsic for testing ConstantIslands.
Creating tests for the ConstantIslands pass is very difficult, since it depends
on precise layout details. Having the ability to precisely inject a number of
bytes into the stream helps greatly.

llvm-svn: 221903
2014-11-13 17:58:48 +00:00
Tom Roeder eb7a303d1b Add Forward Control-Flow Integrity.
This commit adds a new pass that can inject checks before indirect calls to
make sure that these calls target known locations. It supports three types of
checks and, at compile time, it can take the name of a custom function to call
when an indirect call check fails. The default failure function ignores the
error and continues.

This pass incidentally moves the function JumpInstrTables::transformType from
private to public and makes it static (with a new argument that specifies the
table type to use); this is so that the CFI code can transform function types
at call sites to determine which jump-instruction table to use for the check at
that site.

Also, this removes support for jumptables in ARM, pending further performance
analysis and discussion.

Review: http://reviews.llvm.org/D4167
llvm-svn: 221708
2014-11-11 21:08:02 +00:00
Oliver Stannard 8c2c67e63c LLVM incorrectly folds xor into select
LLVM replaces the SelectionDAG pattern (xor (set_cc cc x y) 1) with
(set_cc !cc x y), which is only correct when the xor has type i1.
Instead, we should check that the constant operand to the xor is all
ones.

llvm-svn: 221693
2014-11-11 17:36:01 +00:00
Lang Hames bcdd304cbb [RegAlloc] Remove reference to the trivial spiller in test case.
This test case was never actually testing the trivial spiller: the -spiller
option has not been hooked up for a while now.

llvm-svn: 221475
2014-11-06 19:24:18 +00:00
Rafael Espindola 1c99344156 Use FileCheck in a few tests.
llvm-svn: 221459
2014-11-06 15:05:51 +00:00
Tim Northover dc0d9e46a5 ARM: try to add extra CS-register whenever stack alignment >= 8.
We currently try to push an even number of registers to preserve 8-byte
alignment during a function's prologue, but only when the stack alignment is
prcisely 8. Many of the reasons for doing it apply also when that alignment > 8
(the extra store is often free, and can save another stack adjustment, though
less frequently for 16-byte stack alignment).

llvm-svn: 221321
2014-11-05 00:27:20 +00:00
Tim Northover 228c943f31 ARM/Dwarf: correctly align stack before callee-saved VPRs
We were making an attempt to do this by adding an extra callee-saved GPR (so
that there was an even number in the list), but when that failed we went ahead
and pushed anyway.

This had a couple of potential issues:
  + The .cfi directives we emit misplaced dN because they were based on
    PrologEpilogInserter's calculation.
  + Unaligned stores can be less efficient.
  + Unaligned stores can actually fault (likely only an issue in niche cases,
    but possible).

This adds a final explicit stack adjustment if all other options fail, so that
the actual locations of the registers match up with where they should be.

llvm-svn: 221320
2014-11-05 00:27:13 +00:00
Charlie Turner 1d8cc909cc Remove the cortex-a9-mp CPU.
This CPU definition is redundant. The Cortex-A9 is defined as
supporting multiprocessing extensions. Remove its definition and
update appropriate tests.

LLVM defines both a cortex-a9 CPU and a cortex-a9-mp CPU. The only
difference between the two CPU definitions in ARM.td is that
cortex-a9-mp contains the feature FeatureMP for multiprocessing
extensions.

This is redundant since the Cortex-A9 is defined as having
multiprocessing extensions in the TRMs. armcc also defines the
Cortex-A9 as having multiprocessing extensions by default.

Change-Id: Ifcadaa6c322be0a33d9d2a39cfdd7da1d75981a7
llvm-svn: 221166
2014-11-03 17:38:00 +00:00
Quentin Colombet c32615dfef [CodeGenPrepare] Move extractelement close to store if they can be combined.
This patch adds an optimization in CodeGenPrepare to move an extractelement
right before a store when the target can combine them.
The optimization may promote any scalar operations to vector operations in the
way to make that possible.


** Context **

Some targets use different register files for both vector and scalar operations.
This means that transitioning from one domain to another may incur copy from one
register file to another. These copies are not coalescable and may be expensive.
For example, according to the scheduling model, on cortex-A8 a vector to GPR
move is 20 cycles.


** Motivating Example **

Let us consider an example:
define void @foo(<2 x i32>* %addr1, i32* %dest) {
 %in1 = load <2 x i32>* %addr1, align 8
 %extract = extractelement <2 x i32> %in1, i32 1
 %out = or i32 %extract, 1
 store i32 %out, i32* %dest, align 4
 ret void
}

As it is, this IR generates the following assembly on armv7:
  vldr  d16, [r0]            @vector load  
  vmov.32 r0, d16[1]  @ cross-register-file copy: 20 cycles
  orr r0, r0, #1           @ scalar bitwise or
  str r0, [r1]               @ scalar store
  bx  lr

Whereas we could generate much faster code:
  vldr  d16, [r0]               @ vector load
  vorr.i32  d16, #0x1     @ vector bitwise or
  vst1.32 {d16[1]}, [r1:32] @ vector extract + store
  bx  lr

Half of the computation made in the vector is useless, but this allows to get
rid of the expensive cross-register-file copy.


** Proposed Solution **

To avoid this cross-register-copy penalty, we promote the scalar operations to
vector operations. The penalty will be removed if we manage to promote the whole
chain of computation in the vector domain.
Currently, we do that only when the chain of computation ends by a store and the
target is able to combine an extract with a store.

Stores are the most likely candidates, because other instructions produce values
that would need to be promoted and so, extracted as some point[1]. Moreover,
this is customary that targets feature stores that perform a vector extract (see
AArch64 and X86 for instance).

The proposed implementation relies on the TargetTransformInfo to decide whether
or not it is beneficial to promote a chain of computation in the vector domain.
Unfortunately, this interface is rather inaccurate for this level of details and
although this optimization may be beneficial for X86 and AArch64, the inaccuracy
will lead to the optimization being too aggressive.
Basically in TargetTransformInfo, everything that is legal has a cost of 1,
whereas, even if a vector type is legal, usually a vector operation is slightly
more expensive than its scalar counterpart. That will lead to too many
promotions that may not be counter balanced by the saving of the
cross-register-file copy. For instance, on AArch64 this penalty is just 4
cycles.

For now, the optimization is just enabled for ARM prior than v8, since those
processors have a larger penalty on cross-register-file copies, and the scope is
limited to basic blocks. Because of these two factors, we limit the effects of
the inaccuracy. Indeed, I did not want to build up a fancy cost model with block
frequency and everything on top of that.

[1] We can imagine targets that can combine an extractelement with  other
instructions than just stores. If we want to go into that direction, the current
interfaces must be augmented and, moreover, I think this becomes a global isel
problem.

Differential Revision: http://reviews.llvm.org/D5921

<rdar://problem/14170854>

llvm-svn: 220978
2014-10-31 17:52:53 +00:00
Tim Northover a94cd25188 ARM: test default values for TAG_CPU_unaligned_access attribute.
It should be on for every target that supports unaligned accesses (e.g. not
v6m).

Patch by Charlie Turner.

llvm-svn: 220912
2014-10-30 17:05:44 +00:00
Oliver Stannard 79efe41a0c [ARM] Select VMAXNM and VMINNM regardless of operand order
Currently, the ARM backend will select the VMAXNM and VMINNM for these C
expressions:
  (a < b) ? a : b
  (a > b) ? a : b
but not these expressions:
  (a > b) ? b : a
  (a < b) ? b : a

This patch allows all of these expressions to be matched.

llvm-svn: 220671
2014-10-27 09:23:02 +00:00
Renato Golin 6fb9c2ea70 Do not emit intermediate register for zero FP immediate
This updates check for double precision zero floating point constant to allow
use of instruction with immediate value rather than temporary register.
Currently "a == 0.0", where "a" is of "double" type generates:

vmov.i32        d16, #0x0
vcmpe.f64       d0, d16

With this change it becomes:

vcmpe.f64        d0, #0

Patch by Sergey Dmitrouk.

llvm-svn: 220486
2014-10-23 15:31:50 +00:00
Akira Hatanaka 2ee0e9e6ee [ARM, stack protector] If supported, use armv7 instructions.
This commit enables using movt/movw to load the stack guard address:

movw r0, :lower16:(L_g3$non_lazy_ptr-(LPC0_0+8))
movt r0, :upper16:(L_g3$non_lazy_ptr-(LPC0_0+8))
ldr r0, [pc, r0]

Previously a pc-relative load was emitted:

ldr r0, LCPI0_0
ldr r0, [pc, r0]

rdar://problem/18740489

llvm-svn: 220470
2014-10-23 04:17:05 +00:00
Tim Northover 23075ccee7 ARM: rework Thumb1 frame index rewriting
The previous code had a few problems, motivating the choices here.

1. It could create instructions clobbering CPSR, but the incoming MachineInstr
   didn't reflect this. A potential source of corruption. This is why the patch
   has a new PseudoInst for before lowering.
2. Similarly, there was some code to handle the incoming instruction not being
   ARMCC::AL, but this would have caused massive problems if it was actually
   invoked when a complex offset needing more than one instruction was requested.
3. It wasn't designed to handle unaligned pointers (or offsets). These should
   probably be minimised anyway, but the code needs to deal with them properly
   regardless.
4. It had some rather dubious ad-hoc code to avoid calling
   emitThumbRegPlusImmediate, a function which should be designed to do precisely
   this job.

We seem to cover the common cases correctly now, and hopefully can enhance
emitThumbRegPlusImmediate to handle any extra optimisations we need to add in
future.

llvm-svn: 220236
2014-10-20 21:28:41 +00:00
Oliver Stannard e8f63a54b4 [ARM] Do not select SMULW[BT] or SMLAW[BT]
The current instruction selection patterns for SMULW[BT] and SMLAW[BT]
are incorrect. These instructions multiply a 32-bit and a 16-bit value
(both signed) and return the top 32 bits of the 48-bit result. This
preserves the 16 bits of overflow, whereas the patterns they currently
match truncate the result to 16 bits then sign extend.

To select these instructions, we would need to match an ISD::SMUL_LOHI,
a sign extend, two shifts and an or. There is no way to match SMUL_LOHI
in an instruction pattern as it defines multiple values, so this would
have to be done in C++. I have raised
http://llvm.org/bugs/show_bug.cgi?id=21297 to cover allowing correct
selection of these instructions.

This fixes http://llvm.org/bugs/show_bug.cgi?id=19396

llvm-svn: 220196
2014-10-20 11:30:35 +00:00
Tim Northover cf6ce0c8f7 ARM: remove ARM/Thumb distinction for preferred alignment.
Thumb1 has legitimate reasons for preferring 32-bit alignment of types
i1/i8/i16, since the 16-bit encoding of "add rD, sp, #imm" requires #imm to be
a multiple of 4. However, this is a trade-off betweem code size and RAM usage;
the DataLayout string is not the best place to represent it even if desired.

So this patch removes the extra Thumb requirements, hopefully making ARM and
Thumb completely compatible in this respect.

llvm-svn: 219734
2014-10-14 22:12:17 +00:00
Tim Northover 9a4c043d67 ARM: allow misaligned local variables in Thumb1 mode.
There's no hard requirement on LLVM to align local variable to 32-bits, so the
Thumb1 frame handling needs to be able to deal with variables that are only
naturally aligned without falling over.

llvm-svn: 219733
2014-10-14 22:12:14 +00:00
Tim Northover aa09ac6e83 ARM: set preferred aggregate alignment to 32 universally.
Before, ARM and Thumb mode code had different preferred alignments, which could
lead to some rather unexpected results. There's justification for reducing it
from the default 64-bits (wasted space), but I don't think there is for going
below 32-bits.

There's no actual ABI change here, just to reassure people.

llvm-svn: 219719
2014-10-14 20:57:26 +00:00
Renato Golin 16ea8ba3bc Adds support for the Cortex-A17 to the ARM backend
Patch by Matthew Wahab.

llvm-svn: 219606
2014-10-13 10:22:19 +00:00
Renato Golin 0595a26c25 Emit unaligned access build attribute for ARM
Patch by Charlie Turner.

llvm-svn: 219301
2014-10-08 12:26:22 +00:00
Duncan P. N. Exon Smith 176b691d32 Revert "Revert "DI: Fold constant arguments into a single MDString""
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 219010
2014-10-03 20:01:09 +00:00
Renato Golin 4e31ae1051 Revert 202433 - Provide a target override for the latest regalloc heuristic
That commit was introduced in order to help investigate a problem in ARM
codegen breaking from commit 202304 (Add a limit to the heuristic that register
allocates instructions in local order). Recent analisys indicated that the
problem no longer exists, so I'm reverting this change.

See PR18996.

llvm-svn: 218981
2014-10-03 12:20:53 +00:00
Duncan P. N. Exon Smith 786cd049fc Revert "DI: Fold constant arguments into a single MDString"
This reverts commit r218914 while I investigate some bots.

llvm-svn: 218918
2014-10-02 22:15:31 +00:00