Summary:
Before this patch, `relaxInstruction` takes three arguments, the first
argument refers to the instruction before relaxation and the third
argument is the output instruction after relaxation. There are two quite
strange things:
1) The first argument's type is `const MCInst &`, the third
argument's type is `MCInst &`, but they may be aliased to the same
variable
2) The backends of ARM, AMDGPU, RISC-V, Hexagon assume that the third
argument is a fresh uninitialized `MCInst` even if `relaxInstruction`
may be called like `relaxInstruction(Relaxed, STI, Relaxed)` in a
loop.
In this patch, we drop the thrid argument, and let `relaxInstruction`
directly modify the given instruction. Also, this patch fixes the bug https://bugs.llvm.org/show_bug.cgi?id=45580, which is introduced by D77851, and
breaks the assumption of ARM, AMDGPU, RISC-V, Hexagon.
Reviewers: Razer6, MaskRay, jyknight, asb, luismarques, enderby, rtaylor, colinl, bcain
Reviewed By: Razer6, MaskRay, bcain
Subscribers: bcain, nickdesaulniers, nathanchance, wuzish, annita.zhang, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, tpr, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78364
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary: If an object file ends with a relocation that is smaller
than 4 bytes we will write outside the Data array and trigger an
"Invalid index" assertion.
Reviewers: jyknight, venkatra
Reviewed By: jyknight
Subscribers: fedor.sergeev, jrtc27, llvm-commits
Differential Revision: https://reviews.llvm.org/D50971
llvm-svn: 340736
Summary: When compiling with -fpic, in contrast to -fPIC, use only the
immediate field to index into the GOT. This saves space if the GOT is
known to be small. The linker will warn if the GOT is too large for
this method.
Reviewers: jyknight, venkatra
Reviewed By: jyknight
Subscribers: brad, fedor.sergeev, jrtc27, llvm-commits
Differential Revision: https://reviews.llvm.org/D47136
llvm-svn: 334383
On targets like Arm some relaxations may only be performed when certain
architectural features are available. As functions can be compiled with
differing levels of architectural support we must make a judgement on
whether we can relax based on the MCSubtargetInfo for the function. This
change passes through the MCSubtargetInfo for the function to
fixupNeedsRelaxation so that the decision on whether to relax can be made
per function. In this patch, only the ARM backend makes use of this
information. We must also pass the MCSubtargetInfo to applyFixup because
some fixups skip error checking on the assumption that relaxation has
occurred, to prevent code-generation errors applyFixup must see the same
MCSubtargetInfo as fixupNeedsRelaxation.
Differential Revision: https://reviews.llvm.org/D44928
llvm-svn: 334078
With this we gain a little flexibility in how the generic object
writer is created.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47045
llvm-svn: 332868
To make this work I needed to add an endianness field to MCAsmBackend
so that writeNopData() implementations know which endianness to use.
Part of PR37466.
Differential Revision: https://reviews.llvm.org/D47035
llvm-svn: 332857
Currently it's not possible to access MCSubtargetInfo from a TgtMCAsmBackend.
D20830 threaded an MCSubtargetInfo reference through
MCAsmBackend::relaxInstruction, but this isn't the only function that would
benefit from access. This patch removes the Triple and CPUString arguments
from createMCAsmBackend and replaces them with MCSubtargetInfo.
This patch just changes the interface without making any intentional
functional changes. Once in, several cleanups are possible:
* Get rid of the awkward MCSubtargetInfo handling in ARMAsmBackend
* Support 16-bit instructions when valid in MipsAsmBackend::writeNopData
* Get rid of the CPU string parsing in X86AsmBackend and just use a SubtargetFeature for HasNopl
* Emit 16-bit nops in RISCVAsmBackend::writeNopData if the compressed instruction set extension is enabled (see D41221)
This change initially exposed PR35686, which has since been resolved in r321026.
Differential Revision: https://reviews.llvm.org/D41349
llvm-svn: 321692
functions.
This makes the ownership of the resulting MCObjectWriter clear, and allows us
to remove one instance of MCObjectStreamer's bizarre "holding ownership via
someone else's reference" trick.
llvm-svn: 315327
Summary:
Some SPARC TLS relocations were applying nontrivial adjustments
to zero value, leading to unexpected non-zero values in ELF and then
Solaris linker failures.
Getting rid of these adjustments.
Fixes PR33825.
Reviewers: rafael, asb, jyknight
Subscribers: joerg, jyknight, llvm-commits
Differential Revision: https://reviews.llvm.org/D35567
llvm-svn: 308978
The issue is not if the value is pcrel. It is whether we have a
relocation or not.
If we have a relocation, the static linker will select the upper
bits. If we don't have a relocation, we have to do it.
llvm-svn: 307730
processFixupValue is called on every relaxation iteration. applyFixup
is only called once at the very end. applyFixup is then the correct
place to do last minute changes and value checks.
While here, do proper range checks again for fixup_arm_thumb_bl. We
used to do it, but dropped because of thumb2. We now do it again, but
use the thumb2 range.
llvm-svn: 306177
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
A number of backends (AArch64, MIPS, ARM) have been using
MCContext::reportError to report issues such as out-of-range fixup values in
their TgtAsmBackend. This is great, but because MCContext couldn't easily be
threaded through to the adjustFixupValue helper function from its usual
callsite (applyFixup), these backends ended up adding an MCContext* argument
and adding another call to applyFixup to processFixupValue. Adding an
MCContext parameter to applyFixup makes this unnecessary, and even better -
applyFixup can take a reference to MCContext rather than a potentially null
pointer.
Differential Revision: https://reviews.llvm.org/D30264
llvm-svn: 299529
Some targets, notably AArch64 for ILP32, have different relocation encodings
based upon the ABI. This is an enabling change, so a future patch can use the
ABIName from MCTargetOptions to chose which relocations to use. Tested using
check-llvm.
The corresponding change to clang is in: http://reviews.llvm.org/D16538
Patch by: Joel Jones
Differential Revision: https://reviews.llvm.org/D16213
llvm-svn: 276654
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).
For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.
This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.
This commit also contains a trivial patch to clang to account for the C++ API
change. Thanks go to Pavel Labath for fixing LLDB for me.
Reviewers: rengolin
Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10969
llvm-svn: 247692
Summary:
This is the first patch in the series to migrate Triple's (which are ambiguous)
to TargetTuple's (which aren't).
For the moment, TargetTuple simply passes all requests to the Triple object it
holds. Once it has replaced Triple, it will start to implement the interface in
a more suitable way.
This change makes some changes to the public C++ API. In particular,
InitMCSubtargetInfo(), createMCRelocationInfo(), and createMCSymbolizer()
now take TargetTuples instead of Triples. The other public C++ API's have
been left as-is for the moment to reduce patch size.
This commit also contains a trivial patch to clang to account for the C++ API
change.
Reviewers: rengolin
Subscribers: jyknight, dschuff, arsenm, rampitec, danalbert, srhines, javed.absar, dsanders, echristo, emaste, jholewinski, tberghammer, ted, jfb, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10969
llvm-svn: 247683
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.
Reviewers: echristo, rafael
Reviewed By: rafael
Subscribers: rafael, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D10243
llvm-svn: 239464
I started trying to fix a small issue, but this code has seen a small fix too
many.
The old code was fairly convoluted. Some of the issues it had:
* It failed to check if a symbol difference was in the some section when
converting a relocation to pcrel.
* It failed to check if the relocation was already pcrel.
* The pcrel value computation was wrong in some cases (relocation-pc.s)
* It was missing quiet a few cases where it should not convert symbol
relocations to section relocations, leaving the backends to patch it up.
* It would not propagate the fact that it had changed a relocation to pcrel,
requiring a quiet nasty work around in ARM.
* It was missing comments.
llvm-svn: 205076
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.
Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.
llvm-svn: 198685
Fangrui Song