Summary:
We rely on this in our CHERI backend to address the GOT by generating a
$pc-relative addresses. For this we emit the following code sequence:
lui $1, %pcrel_hi(_CHERI_CAPABILITY_TABLE_-8)
daddiu $1, $1, %pcrel_lo(_CHERI_CAPABILITY_TABLE_-4)
cgetpccincoffset $c1, $1
However, without this change the addend is implicitly converted to
UINT32_MAX and an invalid pointer value is generated.
Reviewers: atanasyan
Reviewed By: atanasyan
Subscribers: merge_guards_bot, sdardis, hiraditya, jrtc27, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70953
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
The callee address is added as an optional operand (MCSymbol) in
AdjustInstrPostInstrSelection() and then used by asm printer to insert:
'.reloc tmplabel, R_MIPS_JALR, symbol
tmplabel:'.
Controlled with '-mips-jalr-reloc', default is true.
Differential revision: https://reviews.llvm.org/D56694
llvm-svn: 351485
Expand on LONG_BRANCH_LUi and LONG_BRANCH_(D)ADDiu pseudo
instructions by creating variants which support
less operands/accept GPR64Opnds as their operand in order
to appease the machine verifier pass.
Differential Revision: https://reviews.llvm.org/D53977
llvm-svn: 346133
Extend LONG_BRANCH_LUi and LONG_BRANCH_ADDiu pseudo instructions with
additional flag, so instead of always lowering to lui %hi(...),
addiu %lo(...) or addiu %hi(...), now they can lower to either %lo, %hi,
%higher or %highest depending on the added flag.
Differential Revision: https://reviews.llvm.org/D47941
llvm-svn: 334490
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
The summary is that it moves the mangling earlier and replaces a few
calls to .addExternalSymbol with addSym.
I originally wanted to replace all the uses of addExternalSymbol with
addSym, but noticed it was a lot of work and doesn't need to be done
all at once.
llvm-svn: 240395
%higher and %highest can have non-zero values only for offsets greater
than 2GB, which is highly unlikely, if not impossible when compiling a
single function. This makes long branch for MIPS64 3 instructions smaller.
Differential Revision: http://llvm-reviews.chandlerc.com/D3281.diff
llvm-svn: 209678
target cannot be determined accurately. This is the case for NaCl where the
sandboxing instructions are added in MC layer, after the MipsLongBranch pass.
It is also the case when the code has inline assembly. Instead of calculating
offset in the MipsLongBranch pass, use %hi(sym1 - sym2) and %lo(sym1 - sym2)
expressions that are resolved during the fixup.
This patch also deletes microMIPS test file test/CodeGen/Mips/micromips-long-branch.ll
and implements microMIPS CHECKs in a much simpler way in a file
test/CodeGen/Mips/longbranch.ll, together with MIPS32 and MIPS64.
llvm-svn: 207656
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
llvm-svn: 169131
assembler such as shifts greater than 32. In the case
of direct object, the code gen needs to do this lowering
since the assembler is not involved.
With the advent of the llvm-mc assembler, it also needs
to do the same lowering.
This patch makes that specific lowering code accessible
to both the direct object output and the assembler.
This patch does not affect generated output.
llvm-svn: 163287
on the size of the extraction and its position in the 64 bit word.
This patch allows support of the dext transformations with mips64 direct
object output.
0 <= msb < 32 0 <= lsb < 32 0 <= pos < 32 1 <= size <= 32
DINS
The field is entirely contained in the right-most word of the doubleword
32 <= msb < 64 0 <= lsb < 32 0 <= pos < 32 2 <= size <= 64
DINSM
The field straddles the words of the doubleword
32 <= msb < 64 32 <= lsb < 64 32 <= pos < 64 1 <= size <= 32
DINSU
The field is entirely contained in the left-most word of the doubleword
llvm-svn: 163010
on the size of the extraction and its position in the 64 bit word.
This patch allows support of the dext transformations with mips64 direct
object output.
0 <= msb < 32 0 <= lsb < 32 0 <= pos < 32 1 <= size <= 32
DINS
The field is entirely contained in the right-most word of the doubleword
32 <= msb < 64 0 <= lsb < 32 0 <= pos < 32 2 <= size <= 64
DINSM
The field straddles the words of the doubleword
32 <= msb < 64 32 <= lsb < 64 32 <= pos < 64 1 <= size <= 32
DINSU
The field is entirely contained in the left-most word of the doubleword
llvm-svn: 162782
Mips shift instructions DSLL, DSRL and DSRA are transformed into
DSLL32, DSRL32 and DSRA32 respectively if the shift amount is between
32 and 63
Here is a description of DSLL:
Purpose: Doubleword Shift Left Logical Plus 32
To execute a left-shift of a doubleword by a fixed amount--32 to 63 bits
Description: GPR[rd] <- GPR[rt] << (sa+32)
The 64-bit doubleword contents of GPR rt are shifted left, inserting
zeros into the emptied bits; the result is placed in
GPR rd. The bit-shift amount in the range 0 to 31 is specified by sa.
This patch implements the direct object output of these instructions.
llvm-svn: 160277
- Remove code which lowers pseudo SETGP01.
- Fix LowerSETGP01. The first two of the three instructions that are emitted to
initialize the global pointer register now use register $2.
- Stop emitting .cpload directive.
llvm-svn: 156689
them as machine instructions. Directives ".set noat" and ".set at" are now
emitted only at the beginning and end of a function except in the case where
they are emitted to enclose .cpload with an immediate operand that doesn't fit
in 16-bit field or unaligned load/stores.
Also, make the following changes:
- Remove function isUnalignedLoadStore and use a switch-case statement to
determine whether an instruction is an unaligned load or store.
- Define helper function CreateMCInst which generates an instance of an MCInst
from an opcode and a list of operands.
llvm-svn: 153552
reserving a physical register ($gp or $28) for that purpose.
This will completely eliminate loads that restore the value of $gp after every
function call, if the register allocator assigns a callee-saved register, or
eliminate unnecessary loads if it assigns a temporary register.
example:
.cpload $25 // set $gp.
...
.cprestore 16 // store $gp to stack slot 16($sp).
...
jalr $25 // function call. clobbers $gp.
lw $gp, 16($sp) // not emitted if callee-saved reg is chosen.
...
lw $2, 4($gp)
...
jalr $25 // function call.
lw $gp, 16($sp) // not emitted if $gp is not live after this instruction.
...
llvm-svn: 151402
- lower unaligned loads/stores.
- encode the size operand of instructions INS and EXT.
- emit relocation information needed for JAL (jump-and-link).
llvm-svn: 145113
"With this patch we can now generate runnable Mips code through LLVM
direct object emission. We have run numerous simple programs, both C
and C++ and with -O0 and -O3 from the output. The code is not production
ready, but quite useful for experimentation." Patch and message by
Jack Carter
llvm-svn: 144414
Mips1 does not support double precision loads or stores, therefore two single
precision loads or stores must be used in place of these instructions. This
patch treats double precision loads and stores as if they are legal
instructions until MCInstLowering, instead of generating the single precision
instructions during instruction selection or Prolog/Epilog code insertion.
Without the changes made in this patch, llc produces code that has the same
problem described in r137484 or bails out when
MipsInstrInfo::storeRegToStackSlot or loadRegFromStackSlot is called before
register allocation.
llvm-svn: 137711
