Commit Graph

6568 Commits

Author SHA1 Message Date
Jim Grosbach
5bc79cc4e8 ARM: Use MCTargetAsmParser::validateTargetOperandClass().
Use the validateTargetOperandClass() hook to match literal '#0' operands in
InstAlias definitions. Previously this required per-instruction C++ munging of the
operand list, but not is handled as a natural part of the matcher. Much better.

No additional tests are required, as the pre-existing tests for these instructions
exercise the new behaviour as being functionally equivalent to the old.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174488 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-06 06:00:11 +00:00
Jakob Stoklund Olesen
fc74327444 Move MRI liveouts to ARM return instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174406 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-05 18:08:40 +00:00
Arnold Schwaighofer
e2d5590c33 ARM cost model: Cost for scalar integer casts and floating point conversions
Also adds some costs for vector integer float conversions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174371 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-05 14:05:55 +00:00
Arnold Schwaighofer
a7ad84851b ARM cost model: Penalize insertelement into D subregisters
Swift has a renaming dependency if we load into D subregisters. We don't have a
way of distinguishing between insertelement operations of values from loads and
other values. Therefore, we are pessimistic for now (The performance problem
showed up in example 14 of gcc-loops).

radar://13096933

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174300 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-04 02:52:05 +00:00
Chandler Carruth
27aacedf7d Switch the code added in r173885 to use the new, shiny RTTI
infrastructure on MCStreamer to test for whether there is an
MCELFStreamer object available.

This is just a cleanup on the AsmPrinter side of things, moving ad-hoc
tests of random APIs to a direct type query. But the AsmParser
completely broken. There were no tests, it just blindly cast its
streamer to an MCELFStreamer and started manipulating it.

I don't have a test case -- this actually failed on LLVM's own
regression test suite. Unfortunately the failure only appears when the
stars, compilers, and runtime align to misbehave when we read a pointer
to a formatted_raw_ostream as-if it were an MCAssembler. =/

UBSan would catch this immediately.

Many thanks to Matt for doing about 80% of the debugging work here in
GDB, Jim for helping to explain how exactly to fix this, and others for
putting up with the hair pulling that ensued during debugging it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174118 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 23:43:14 +00:00
Chandler Carruth
5da3665cc5 Give the MCStreamer class hierarchy LLVM RTTI facilities for use with
isa<> and dyn_cast<>. In several places, code is already hacking around
the absence of this, and there seem to be several interfaces that might
be lifted and/or devirtualized using this.

This change was based on a discussion with Jim Grosbach about how best
to handle testing for specific MCStreamer subclasses. He said that this
was the correct end state, and everything else was too hacky so
I decided to just make it so.

No functionality should be changed here, this is just threading the kind
through all the constructors and setting up the classof overloads.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174113 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 23:29:57 +00:00
Chad Rosier
108fb3202a [PEI] Pass the frame index operand number to the eliminateFrameIndex function.
Each target implementation was needlessly recomputing the index.
Part of rdar://13076458

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174083 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 20:02:54 +00:00
Tim Northover
72062f5744 Add AArch64 as an experimental target.
This patch adds support for AArch64 (ARM's 64-bit architecture) to
LLVM in the "experimental" category. Currently, it won't be built
unless requested explicitly.

This initial commit should have support for:
    + Assembly of all scalar (i.e. non-NEON, non-Crypto) instructions
      (except the late addition CRC instructions).
    + CodeGen features required for C++03 and C99.
    + Compilation for the "small" memory model: code+static data <
      4GB.
    + Absolute and position-independent code.
    + GNU-style (i.e. "__thread") TLS.
    + Debugging information.

The principal omission, currently, is performance tuning.

This patch excludes the NEON support also reviewed due to an outbreak of
batshit insanity in our legal department. That will be committed soon bringing
the changes to precisely what has been approved.

Further reviews would be gratefully received.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174054 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 12:12:40 +00:00
Eli Bendersky
0f156af831 Add a special ARM trap encoding for NaCl.
More details in this thread: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130128/163783.html

Patch by JF Bastien



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173943 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-30 16:30:19 +00:00
Logan Chien
620d5bd8e4 Add missing header and test cases for r173939.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173941 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-30 15:48:50 +00:00
Logan Chien
52b1b3bbc6 Override virtual function for ARM EH directives.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173939 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-30 15:39:04 +00:00
Jack Carter
97130e2b3d This patch implements runtime ARM specific
setting of ELF header e_flags.

Contributer: Jack Carter
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173885 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-30 02:24:33 +00:00
Jack Carter
9a7bf438b5 This patch reworks how llvm targets set
and update ELF header e_flags.

Currently gathering information such as symbol, 
section and data is done by collecting it in an 
MCAssembler object. From MCAssembler and MCAsmLayout 
objects ELFObjectWriter::WriteObject() forms and 
streams out the ELF object file.

This patch just adds a few members to the MCAssember 
class to store and access the e_flag settings. It 
allows for runtime additions to the e_flag by 
assembler directives. The standalone assembler can 
get to MCAssembler from getParser().getStreamer().getAssembler().

This patch is the generic infrastructure and will be
followed by patches for ARM and Mips for their target 
specific use.

Contributer: Jack Carter
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173882 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-30 02:09:52 +00:00
Renato Golin
0261cea689 Adding simple cast cost to ARM
Changing ARMBaseTargetMachine to return ARMTargetLowering intead of
the generic one (similar to x86 code).

Tests showing which instructions were added to cast when necessary
or cost zero when not. Downcast to 16 bits are not lowered in NEON,
so costs are not there yet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173849 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-29 23:31:38 +00:00
Tim Northover
0adfdedacb Fix 64-bit atomic operations in Thumb mode.
The ARM and Thumb variants of LDREXD and STREXD have different constraints and
take different operands. Previously the code expanding atomic operations didn't
take this into account and asserted in Thumb mode.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173780 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-29 09:06:13 +00:00
Evan Cheng
8688a58c53 Teach SDISel to combine fsin / fcos into a fsincos node if the following
conditions are met:
1. They share the same operand and are in the same BB.
2. Both outputs are used.
3. The target has a native instruction that maps to ISD::FSINCOS node or
   the target provides a sincos library call.

Implemented the generic optimization in sdisel and enabled it for
Mac OSX. Also added an additional optimization for x86_64 Mac OSX by
using an alternative entry point __sincos_stret which returns the two
results in xmm0 / xmm1.

rdar://13087969
PR13204


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173755 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-29 02:32:37 +00:00
Silviu Baranga
4a9256f265 Fixed the condition codes for the atomic64 min/umin code generation on ARM. If the sutraction of the higher 32 bit parts gives a 0 result, we need to do the store operation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173437 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-25 10:39:49 +00:00
Quentin Colombet
19d5433716 Follow up of commit r172472.
Refactor the big if/else sequence into one string switch for ARM subtype selection.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172475 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-14 21:34:09 +00:00
Quentin Colombet
398db9368d Complete the existing support of ARM v6m, v7m, and v7em, i.e., respectively cortex-m0, cortex-m3, and cortex-m4 on the backend side.
Adds new subtype values for the MachO format and use them when the related triple are set.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172472 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-14 21:07:43 +00:00
Joel Jones
5573de8493 Fix description of ARMOperand
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172011 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 22:34:16 +00:00
Nadav Rotem
14925e6b88 ARM Cost model: Use the size of vector registers and widest vectorizable instruction to determine the max vectorization factor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172010 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 22:29:00 +00:00
Eric Christopher
1ced208be9 Last in the series of removing unnecessary '0' arguments for
address space. Reordered the EmitULEB128IntValue arguments to
make this easier.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171949 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 03:52:05 +00:00
Andrew Trick
47579cf390 MIsched: add an ILP window property to machine model.
This was an experimental option, but needs to be defined
per-target. e.g. PPC A2 needs to aggressively hide latency.

I converted some in-order scheduling tests to A2. Hal is working on
more test cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171946 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 03:36:49 +00:00
Eric Christopher
68ca56285f These functions have default arguments of 0 for the last arg. Use
them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171933 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 01:57:54 +00:00
Nadav Rotem
83be7b0dd3 Cost Model: Move the 'max unroll factor' variable to the TTI and add initial Cost Model support on ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171928 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 01:15:42 +00:00
Eli Bendersky
251040bc18 Renamed MCInstFragment to MCRelaxableFragment and added some comments.
No change in functionality.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171822 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-08 00:22:56 +00:00
Jim Grosbach
00b53c1ad7 ARM: Copy-paste error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171790 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 21:24:35 +00:00
Jim Grosbach
54f2187eac ARM: Fix a few copy-paste errors.
s/X86/ARM/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171789 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 21:12:13 +00:00
Jordan Rose
3ebe59c892 Change SMRange to be half-open (exclusive end) instead of closed (inclusive)
This is necessary not only for representing empty ranges, but for handling
multibyte characters in the input. (If the end pointer in a range refers to
a multibyte character, should it point to the beginning or the end of the
character in a char array?) Some of the code in the asm parsers was already
assuming this anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171765 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 19:00:49 +00:00
Tim Northover
0c63e64af6 Add LICENSE.TXT covering contributions made by ARM.
Absent a Contributor's License Agreement (CLA) with an LLVM legal entity and as
reviewed and agreed with Chris Lattner, add a patent license covering future
contributions from ARM until there is a CLA. This is to make explicit ARM's
grant of patent rights to recipients of LLVM containing ARM-contributed
material.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171721 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 10:04:49 +00:00
Chandler Carruth
be04929f7f Move TargetTransformInfo to live under the Analysis library. This no
longer would violate any dependency layering and it is in fact an
analysis. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171686 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 03:08:10 +00:00
Chandler Carruth
aeef83c6af Switch TargetTransformInfo from an immutable analysis pass that requires
a TargetMachine to construct (and thus isn't always available), to an
analysis group that supports layered implementations much like
AliasAnalysis does. This is a pretty massive change, with a few parts
that I was unable to easily separate (sorry), so I'll walk through it.

The first step of this conversion was to make TargetTransformInfo an
analysis group, and to sink the nonce implementations in
ScalarTargetTransformInfo and VectorTargetTranformInfo into
a NoTargetTransformInfo pass. This allows other passes to add a hard
requirement on TTI, and assume they will always get at least on
implementation.

The TargetTransformInfo analysis group leverages the delegation chaining
trick that AliasAnalysis uses, where the base class for the analysis
group delegates to the previous analysis *pass*, allowing all but tho
NoFoo analysis passes to only implement the parts of the interfaces they
support. It also introduces a new trick where each pass in the group
retains a pointer to the top-most pass that has been initialized. This
allows passes to implement one API in terms of another API and benefit
when some other pass above them in the stack has more precise results
for the second API.

The second step of this conversion is to create a pass that implements
the TargetTransformInfo analysis using the target-independent
abstractions in the code generator. This replaces the
ScalarTargetTransformImpl and VectorTargetTransformImpl classes in
lib/Target with a single pass in lib/CodeGen called
BasicTargetTransformInfo. This class actually provides most of the TTI
functionality, basing it upon the TargetLowering abstraction and other
information in the target independent code generator.

The third step of the conversion adds support to all TargetMachines to
register custom analysis passes. This allows building those passes with
access to TargetLowering or other target-specific classes, and it also
allows each target to customize the set of analysis passes desired in
the pass manager. The baseline LLVMTargetMachine implements this
interface to add the BasicTTI pass to the pass manager, and all of the
tools that want to support target-aware TTI passes call this routine on
whatever target machine they end up with to add the appropriate passes.

The fourth step of the conversion created target-specific TTI analysis
passes for the X86 and ARM backends. These passes contain the custom
logic that was previously in their extensions of the
ScalarTargetTransformInfo and VectorTargetTransformInfo interfaces.
I separated them into their own file, as now all of the interface bits
are private and they just expose a function to create the pass itself.
Then I extended these target machines to set up a custom set of analysis
passes, first adding BasicTTI as a fallback, and then adding their
customized TTI implementations.

The fourth step required logic that was shared between the target
independent layer and the specific targets to move to a different
interface, as they no longer derive from each other. As a consequence,
a helper functions were added to TargetLowering representing the common
logic needed both in the target implementation and the codegen
implementation of the TTI pass. While technically this is the only
change that could have been committed separately, it would have been
a nightmare to extract.

The final step of the conversion was just to delete all the old
boilerplate. This got rid of the ScalarTargetTransformInfo and
VectorTargetTransformInfo classes, all of the support in all of the
targets for producing instances of them, and all of the support in the
tools for manually constructing a pass based around them.

Now that TTI is a relatively normal analysis group, two things become
straightforward. First, we can sink it into lib/Analysis which is a more
natural layer for it to live. Second, clients of this interface can
depend on it *always* being available which will simplify their code and
behavior. These (and other) simplifications will follow in subsequent
commits, this one is clearly big enough.

Finally, I'm very aware that much of the comments and documentation
needs to be updated. As soon as I had this working, and plausibly well
commented, I wanted to get it committed and in front of the build bots.
I'll be doing a few passes over documentation later if it sticks.

Commits to update DragonEgg and Clang will be made presently.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171681 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 01:37:14 +00:00
Chandler Carruth
0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
Chandler Carruth
58a2cbef4a Resort the #include lines in include/... and lib/... with the
utils/sort_includes.py script.

Most of these are updating the new R600 target and fixing up a few
regressions that have creeped in since the last time I sorted the
includes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171362 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 10:22:59 +00:00
Bill Wendling
8b62abdd7b Remove the Function::getRetAttributes method in favor of using the AttributeSet accessor method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171256 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-30 13:01:51 +00:00
Bill Wendling
831737d329 Remove the Function::getFnAttributes method in favor of using the AttributeSet
directly.

This is in preparation for removing the use of the 'Attribute' class as a
collection of attributes. That will shift to the AttributeSet class instead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171253 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-30 10:32:01 +00:00
Benjamin Kramer
791dbb3e5f Use a std::string rather than a dynamically allocated char* buffer.
This affords us to use std::string's allocation routines and use the destructor
for the memory management. Switching to that also means that we can use
operator==(const std::string&, const char *) to perform the string comparison
rather than resorting to libc functionality (i.e. strcmp).

Patch by Saleem Abdulrasool!

Differential Revision: http://llvm-reviews.chandlerc.com/D230

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171042 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-24 19:23:30 +00:00
Benjamin Kramer
4e23ebe766 Cleanup compiler warnings on discarding type qualifiers in casts. Switch to C++ style casts.
Patch by Saleem Abdulrasool!

Differential Revision: http://llvm-reviews.chandlerc.com/D204

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170917 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-21 19:09:53 +00:00
Roman Divacky
38b06020db Remove duplicate includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170902 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-21 17:06:44 +00:00
Quentin Colombet
e0f1d712f6 Add ARM cortex-r5 subtarget.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170840 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-21 04:35:05 +00:00
Jakob Stoklund Olesen
be06aacaa9 Add an MF argument to MI::copyImplicitOps().
This function is often used to decorate dangling instructions, so a
context reference is required to allocate memory for the operands.

Also add a corresponding MachineInstrBuilder method.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170797 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 22:54:02 +00:00
Jakob Stoklund Olesen
b9efafe54d MachineInstrBuilderize ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170795 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 22:53:55 +00:00
Bob Wilson
103b4a571e Revert "Adding support for llvm.arm.neon.vaddl[su].* and"
This reverts r170694.  The operations can be represented in IR without
adding any new intrinsics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170765 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 21:09:38 +00:00
Evan Cheng
139e407d52 On some ARM cpus, flags setting movs with shifter operand, i.e. lsl, lsr, asr,
are more expensive than the non-flag setting variant. Teach thumb2 size
reduction pass to avoid generating them unless we are optimizing for size.

rdar://12892707


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170728 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 19:59:30 +00:00
Roman Divacky
6af228a92a Remove MCTargetAsmLexer and its derived classes now that edis,
its only user, is gone.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170699 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 14:43:30 +00:00
Renato Golin
332bd79951 Adding support for llvm.arm.neon.vaddl[su].* and
llvm.arm.neon.vsub[su].* intrinsics.

Patch by Pete Couperus <pjcoup@gmail.com>



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170694 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 13:52:11 +00:00
Jim Grosbach
fbf3b4a076 MC: Add MCInstrDesc::mayAffectControlFlow() method.
MC disassembler clients (LLDB) are interested in querying if an
instruction may affect control flow other than by virtue of being
an explicit branch instruction. For example, instructions which
write directly to the PC on some architectures.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170610 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 23:38:53 +00:00
Jakob Stoklund Olesen
37a942cd52 Remove the explicit MachineInstrBuilder(MI) constructor.
Use the version that also takes an MF reference instead.

It would technically be possible to extract an MF reference from the MI
as MI->getParent()->getParent(), but that would not work for MIs that
are not inserted into any basic block.

Given the reasonably small number of places this constructor was used at
all, I preferred the compile time check to a run time assertion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170588 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 21:31:56 +00:00
Evan Cheng
733c6b1db1 LLVM sdisel normalize bit extraction of the form:
((x & 0xff00) >> 8) << 2
to
 (x >> 6) & 0x3fc

This is general goodness since it folds a left shift into the mask. However,
the trailing zeros in the mask prevents the ARM backend from using the bit
extraction instructions. And worse since the mask materialization may require
an addition instruction. This comes up fairly frequently when the result of 
the bit twiddling is used as memory address. e.g.

 = ptr[(x & 0xFF0000) >> 16]

We want to generate:
  ubfx   r3, r1, #16, #8
  ldr.w  r3, [r0, r3, lsl #2]

vs.
  mov.w  r9, #1020
  and.w  r2, r9, r1, lsr #14
  ldr    r2, [r0, r2]

Add a late ARM specific isel optimization to
ARMDAGToDAGISel::PreprocessISelDAG(). It folds the left shift to the
'base + offset' address computation; change the mask to one which doesn't have
trailing zeros and enable the use of ubfx.

Note the optimization has to be done late since it's target specific and we
don't want to change the DAG normalization. It's also fairly restrictive
as shifter operands are not always free. It's only done for lsh 1 / 2. It's
known to be free on some cpus and they are most common for address
computation.

This is a slight win for blowfish, rijndael, etc.

rdar://12870177


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170581 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 20:16:09 +00:00
Roman Divacky
759e3fa641 Remove edis - the enhanced disassembler. Fixes PR14654.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170578 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 19:55:47 +00:00