Now LLVM assembler cannot process the following code and generates an
error. GNU tools support .set assignment directive with numeric register
name.
```
.set r4, 4
test.s:1:11: error: invalid token in expression
.set r4, $4
^
```
This patch teach assembler to handle such directives correctly.
Unfortunately a numeric register name cannot be represented as an
expression. That's why we have to maintain a separate `StringMap`
in the `MipsAsmParser` to keep mapping between aliases names and
register numbers.
Differential revision: https://reviews.llvm.org/D47464
llvm-svn: 333428
Implement .set dspr2 directive with appropriate feature bits. This
directive is a counterpart of -mattr=dspr2 command line option with the
exception that it does not influence elf header flags.
Patch by Milos Stojanovic.
Differential Revision: https://reviews.llvm.org/D38537
llvm-svn: 314994
Summary:
This is much closer to the way MIPS relocation expressions work
(%hi(foo + 2) rather than %hi(foo) + 2) and removes the need for the
various bodges in MipsAsmParser::evaluateRelocExpr().
Removing those bodges ensures that the constant stored in MCValue is the
full 32 or 64-bit (depending on ABI) offset from the symbol. This will be used
to correct the %hi/%lo matching needed to sort the relocation table correctly.
As part of this:
* Gave MCExpr::print() the ability to omit parenthesis when emitting a
symbol reference inside a MipsMCExpr operator like %hi(X). Without this
we print things like %lo(($L1)).
* %hi(%neg(%gprel(X))) is now three MipsMCExpr's instead of one. Most of
the related special cases have been removed or moved to MipsMCExpr. We
can remove the rest as we gain support for the less common relocations
when they are not part of this specific combination.
* Renamed MipsMCExpr::VariantKind and the enum prefix ('VK_') to avoid confusion
with MCSymbolRefExpr::VariantKind and its prefix (also 'VK_').
* fixup_Mips_GOT_Local and fixup_Mips_GOT_Global were found to be identical
and merged into fixup_Mips_GOT.
* MO_GOT16 and MO_GOT turned out to be identical and have been merged into
MO_GOT.
* VK_Mips_GOT and VK_Mips_GOT16 turned out to be the same thing so they
have been merged into MEK_GOT
Reviewers: sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D19716
llvm-svn: 268379
Summary:
Add a second fixup table to MipsAsmBackend::getFixupKindInfo() to correctly
position llvm-mc's fixup placeholders for big-endian.
See PR19836 for full details of the issue. To summarize, the fixup placeholders
do not account for endianness properly and the implementations of
getFixupKindInfo() for each target are measuring MCFixupKindInfo.TargetOffset
from different ends of the instruction encoding to compensate.
Reviewers: jkolek, zoran.jovanovic, vmedic
Reviewed By: vmedic
Differential Revision: http://reviews.llvm.org/D3889
llvm-svn: 209514
The '.set mips64' directive enables the feature Mips:FeatureMips64
from assembly. Note that it doesn't modify the ELF header as opposed
to the use of -mips64 from the command-line. The reason for this
is that we want to be as compatible as possible with existing assemblers
like GAS.
llvm-svn: 204817
The '.set mips64r2' directive enables the feature Mips:FeatureMips64r2
from assembly. Note that it doesn't modify the ELF header as opposed
to the use of -mips64r2 from the command-line. The reason for this
is that we want to be as compatible as possible with existing assemblers
like GAS.
llvm-svn: 204815
This patch adds .abicalls and .set pic0 support which
affects the ELF ABI and its flags. In addition the patch uses
a common interface for both the MipsTargetSteamer and
MipsObjectStreamer that both the integrated and standalone
assemblers will use for the output for these directives.
llvm-svn: 198646
As we can't make a complete solution now it has been decided to enable .set directive to handle long jump expressions. This will cause parser to report errors when parsing integer based register assignments, for example:
.set r3, will be reported as error. Still, the need for expressions is higher priority as the integer based register assignments are Mips specific and can be avoided using register names.
llvm-svn: 196773
This patch handles LLVM standalone assembler (llvm-mc) ELF flag setting based on input file
directive processing.
Mips assembly requires processing inline directives that directly and
indirectly affect the output ELF header flags. This patch handles one
".abicalls".
To process these directives we are following the model the code generator
uses by storing state in a container as we go through processing and when
we detect the end of input file processing, AsmParser is notified and we
update the ELF header flags through a MipsELFStreamer method with a call from
MCTargetAsmParser::emitEndOfAsmFile(MCStreamer &OutStreamer).
This patch will allow other targets the same functionality.
Jack
llvm-svn: 191982
This patch solves the problem of numeric register values not being accepted:
../set_alias.s:1:11: error: expected valid expression after comma
.set r4,$4
^
The parsing of .set directive is changed and handling of symbols in code
as well to enable this feature.
The test example is added.
Patch by Vladimir Medic
llvm-svn: 182807
Mips have delayslots for certain instructions
like jumps and branches. These are instructions
that follow the branch or jump and are executed
before the jump or branch is completed.
Early Mips compilers could not cope with delayslots
and left them up to the assembler. The assembler would
fill the delayslots with the appropriate instruction,
usually just a nop to allow correct runtime behavior.
The default behavior for this is set with .set reorder.
To tell the assembler that you don't want it to mess with
the delayslot one used .set noreorder.
For backwards compatibility we need to support
.set reorder and have it be the default behavior in the
assembler.
Our support for it is to insert a NOP directly after an
instruction with a delayslot when in .set reorder mode.
Contributer: Vladimir Medic
llvm-svn: 180584
The .set directive in the Mips the assembler can be
used to set the value of a symbol to an expression.
This changes the symbol's value and type to conform
to the expression's.
Syntax: .set symbol, expression
This patch implements the parsing of the above syntax
and enables the parser to use defined symbols when
parsing operands.
Contributor: Vladimir Medic
llvm-svn: 177667
The constructs %hi() and %lo() represent the high and low 16
bits of the address.
Because the 16 bit offset field of an LW instruction is
interpreted as signed, if bit 15 of the low part is 1 then the
low part will act as a negative and 1 needs to be added to the
high part.
Contributer: Vladimir Medic
llvm-svn: 175707
excluding visibility bits.
Mips specific standalone assembler directive "set at".
This directive changes the general purpose register
that the assembler will use when given the symbolic
register name $at.
This does not include negative testing. That will come
in a future patch.
A side affect of this patch recognizes the different
GPR register names for temporaries between old abi
and new abi so a test case for that is included.
Contributer: Vladimir Medic
llvm-svn: 175686
.set option
The patch implements following options
at - lets the assembler use the $at register for macros,
but generates warnings if the source program uses $at
noat - let source programs use $at without issuingwarnings.
noreorder - prevents the assembler from reordering machine
language instructions.
nomacro - causes the assembler to print a warning whenever
an assembler operation generates more than one
machine language instruction.
macro - lets the assembler generate multiple machine instructions
from a single assembler instruction
reorder - lets the assembler reorder machine language
instructions to improve performance
The above variants are parsed and their boolean values set or unset.
The code to actually use them will come later.
Following options are not implemented yet:
nomips16
nomicromips
move
nomove
Contributer: Vladimir Medic
llvm-svn: 165194
Actually these are just stubs for parsing the directives.
Semantic support will come later.
Test cases included
Contributer: Vladimir Medic
llvm-svn: 163364
