ld64 supplies its own Thumb bit for Thumb functions, and intentionally zeroes
out that part of any addend in an object file. But it only does that for
symbols marked N_EXT -- i.e. external symbols. So LLVM should avoid setting
that extra bit in other cases.
llvm-svn: 339007
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
When the branch target of a Thumb2 unconditional or conditonal branch is
resolved at assembly time, no range checking is performed on the result
leading to incorrect immediates. This change adds a range check:
+- 16 Megabytes for unconditional branches, +- 1 Megabyte for the
conditional branch.
Differential Revision: https://reviews.llvm.org/D46306
llvm-svn: 333997
The Thumb BL range is + or - either 16 Megabytes or 4 Megabytes depending
on whether the CPU supports Thumb2 or the v8-m baseline ops. The existing
check for BL range is incorrectly set at +- 32 Megabytes. This change
corrects the higher range and uses the lower range if the featurebits
don't have the necessary support for it.
Differential Revision: https://reviews.llvm.org/D46305
llvm-svn: 333991
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
Inspired by r331508, I did a grep and found these.
Mostly just change from dyn_cast to cast. Some cases also showed a dyn_cast result being converted to bool, so those I changed to isa.
llvm-svn: 331577
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
After D41349, we can now directly access MCSubtargetInfo from
createARM*AsmBackend. This patch makes use of this, avoiding the need to
create a fresh MCSubtargetInfo (which was previously always done with a blank
CPU and feature string). Given the total size of the change remains pretty
tiny and we're removing the old explicit destructor, I changed the STI field
to a reference rather than a pointer.
Differential Revision: https://reviews.llvm.org/D41693
llvm-svn: 321707
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
Summary:
Using c++11 enum classes ensures that only valid enum values are used
for ArchKind, ProfileKind, VersionKind and ISAKind. This removes the
need for checks that the provided values map to a proper enum value,
allows us to get rid of AK_LAST and prevents comparing values from
different enums. It also removes a bunch of static_cast
from unsigned to enum values and vice versa, at the cost of introducing
static casts to access AArch64ARCHNames and ARMARCHNames by ArchKind.
FPUKind and ArchExtKind are the only remaining old-style enum in
TargetParser.h. I think it's beneficial to keep ArchExtKind as old-style
enum, but FPUKind can be converted too, but this patch is quite big, so
could do this in a follow-up patch. I could also split this patch up a
bit, if people would prefer that.
Reviewers: rengolin, javed.absar, chandlerc, rovka
Reviewed By: rovka
Subscribers: aemerson, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D35882
llvm-svn: 309287
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
For ELF, a movw+movt pair is handled as two separate relocations.
If an offset should be applied to the symbol address, this offset is
stored as an immediate in the instruction (as opposed to stored as an
offset in the relocation itself).
Even though the actual value stored in the movt immediate after linking
is the top half of the value, we need to store the unshifted offset
prior to linking. When the relocation is made during linking, the offset
gets added to the target symbol value, and the upper half of the value
is stored in the instruction.
This makes sure that movw+movt with offset symbols get properly
handled, in case the offset addition in the lower half should be
carried over to the upper half.
This makes the output from the additions to the test case match
the output from GNU binutils.
For COFF and MachO, the movw/movt relocations are handled as a pair,
and the overflow from the lower half gets carried over to the movt,
so they should keep the shifted offset just as before.
Differential Revision: https://reviews.llvm.org/D35242
llvm-svn: 307713
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
Summary:
The ARM ELF ABI requires the linker to do interworking for wide
conditional branches from Thumb code to ARM code.
That was pointed out by @peter.smith in the comments for D33436.
Reviewers: rafael, peter.smith, echristo
Reviewed By: peter.smith
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits, peter.smith
Differential Revision: https://reviews.llvm.org/D34447
llvm-svn: 306009
Summary:
Relocations are required for unconditional branches to function symbols with
different execution mode. Without this patch, incorrect branches are
generated for tail calls between functions with different execution
mode.
Reviewers: peter.smith, rafael, echristo, kristof.beyls
Reviewed By: peter.smith
Subscribers: aemerson, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33898
llvm-svn: 304882
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
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
My previous commit r304702 introduced a new case into a switch statement.
This case defined a variable but I forgot to add the curly brackets around the
case to limit the scope.
This change puts the curly braces back in so that the next person that adds a
case doesn't get a build failure. Thanks to avieira for the spot.
Differential Revision: https://reviews.llvm.org/D33931
llvm-svn: 304785
This change adds a new fixup fixup_t2_so_imm for the t2_so_imm_asmoperand
"T2SOImm". The fixup permits code such as:
.L1:
sub r3, r3, #.L2 - .L1
.L2:
to assemble in Thumb2 as well as in ARM state.
The operand predicate isT2SOImm() explicitly doesn't match expressions
containing :upper16: and :lower16: as expressions with these operators
must match the movt and movw instructions.
The test mov r0, foo2 in thumb2-diagnostics is moved to a new file as the
fixup delays the error message till after the assembler has quit due to
the other errors.
As the mov instruction shares the t2_so_imm_asmoperand mov instructions
with a non constant expression now match t2MOVi rather than t2MOVi16 so the
error message is slightly different.
Fixes PR28647
Differential Revision: https://reviews.llvm.org/D33492
llvm-svn: 304702
Summary:
Without using a fixup in this case, BL will be used instead of BLX to
call internal ARM functions from Thumb functions.
Reviewers: rafael, t.p.northover, peter.smith, kristof.beyls
Reviewed By: peter.smith
Subscribers: srhines, echristo, aemerson, rengolin, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33436
llvm-svn: 304413
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
A 64-bit relocation does not exist in 32-bit ARMELF. Report an error
instead of crashing.
PR23870
Patch by Sanne Wouda (sanwou01).
Differential Revision: https://reviews.llvm.org/D28851
llvm-svn: 292373
Its existence is largely historical, apparently we tried to make ARM object
files look maybe-almost-possibly runnable by putting our best guess at the
actual value into relocated locations. Of course, the real linker then comes
along and can completely change things.
But it should only be there for word-sized and movw/movt relocations. It can't
be encoded in branch relocations, and I've seen it mess up validity
calculations twice in the last couple of weeks so the default is clearly problematic.
llvm-svn: 279773
A branch-distance to a Thumb function shouldn't be forced to be odd for
CBZ/CBNZ instructions because (assuming it's within range), it's going to be a
valid, even offset.
llvm-svn: 279665
This is a mechanical change of comments in switches like fallthrough,
fall-through, or fall-thru to use the LLVM_FALLTHROUGH macro instead.
llvm-svn: 278902
Summary:
Fix for the upper bound check that was causing a build failure.
Reviewers: olista01, rengolin, t.p.northover
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D23501
llvm-svn: 278789
Summary:
The assembler currently does not check the branch target for CBZ/CBNZ
instructions, which only permit branching forwards with a positive offset. This
adds validation for the branch target to ensure negative PC-relative offsets are
not encoded into the instruction, whether specified as a literal or as an
assembler symbol.
Reviewers: rengolin, t.p.northover
Subscribers: llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D23312
llvm-svn: 278788
This currently breaks the greendragon clang-stage1-configure-RA/ and
brotli. It is probably just uncovering a pre-existing problem. Reverting
temporarily to get the buildbots green again. A reduced testcase will
follow shortly.
This reverts commit r278659.
llvm-svn: 278711
Summary:
The assembler currently does not check the branch target for CBZ/CBNZ
instructions, which only permit branching forwards with a positive offset. This
adds validation for the branch target to ensure negative PC-relative offsets are
not encoded into the instruction, whether specified as a literal or as an
assembler symbol.
Reviewers: rengolin, t.p.northover
Subscribers: llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D23312
llvm-svn: 278659
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
Some ARM instructions encode 32-bit immediates as a 8-bit integer (0-255)
and a 4-bit rotation (0-30, even) in its least significant 12 bits. The
original fixup, FK_Data_4, patches the instruction by the value bit-to-bit,
regardless of the encoding. For example, assuming the label L1 and L2 are
0x0 and 0x104 respectively, the following instruction:
add r0, r0, #(L2 - L1) ; expects 0x104, i.e., 260
would be assembled to the following, which adds 1 to r0, instead of 260:
e2800104 add r0, r0, #4, 2 ; equivalently 1
The new fixup kind fixup_arm_mod_imm takes care of the encoding:
e2800f41 add r0, r0, #260
Patch by Ting-Yuan Huang!
llvm-svn: 265122
`MCSymbolRefExpr` variant kind for TLSCALL is prefixed with
_ARM_ since this is how it was originally implemented.
The X86_64 version is exactly the same so there's no reason
to create a new variant, we can just rename the existing
one to be machine-independent.
This generalization is the first step to implement support
for GNU2 TLS dialect in MC.
Differential Revision: http://reviews.llvm.org/D18160
llvm-svn: 263515
This was originally committed as r255762, but reverted as it broke windows
bots. Re-commitiing the exact same patch, as the underlying cause was fixed by
r258677.
ARMv8.2-A adds 16-bit floating point versions of all existing VFP
floating-point instructions. This is an optional extension, so all of
these instructions require the FeatureFullFP16 subtarget feature.
The assembly for these instructions uses S registers (AArch32 does not
have H registers), but the instructions have ".f16" type specifiers
rather than ".f32" or ".f64". The top 16 bits of each source register
are ignored, and the top 16 bits of the destination register are set to
zero.
These instructions are mostly the same as the 32- and 64-bit versions,
but they use coprocessor 9 rather than 10 and 11.
Two new instructions, VMOVX and VINS, have been added to allow packing
and extracting two 16-bit floats stored in the top and bottom halves of
an S register.
New fixup kinds have been added for the PC-relative load and store
instructions, but no ELF relocations have been added as they have a
range of 512 bytes.
Differential Revision: http://reviews.llvm.org/D15038
llvm-svn: 258678
ARMv8.2-A adds 16-bit floating point versions of all existing VFP
floating-point instructions. This is an optional extension, so all of
these instructions require the FeatureFullFP16 subtarget feature.
The assembly for these instructions uses S registers (AArch32 does not
have H registers), but the instructions have ".f16" type specifiers
rather than ".f32" or ".f64". The top 16 bits of each source register
are ignored, and the top 16 bits of the destination register are set to
zero.
These instructions are mostly the same as the 32- and 64-bit versions,
but they use coprocessor 9 rather than 10 and 11.
Two new instructions, VMOVX and VINS, have been added to allow packing
and extracting two 16-bit floats stored in the top and bottom halves of
an S register.
New fixup kinds have been added for the PC-relative load and store
instructions, but no ELF relocations have been added as they have a
range of 512 bytes.
Differential Revision: http://reviews.llvm.org/D15038
llvm-svn: 255762
Tim Northover