We were previously codegen'ing these as regular load/store operations and
hoping that the register allocator would allocate registers in ascending order
so that we could apply an LDM/STM combine after register allocation. According
to the commit that first introduced this code (r37179), we planned to teach
the register allocator to allocate the registers in ascending order. This
never got implemented, and up to now we've been stuck with very poor codegen.
A much simpler approach for achiveing better codegen is to create LDM/STM
instructions with identical sets of virtual registers, let the register
allocator pick arbitrary registers and order register lists when printing an
MCInst. This approach also avoids the need to repeatedly calculate offsets
which ultimately ought to be eliminated pre-RA in order to decrease register
pressure.
This is implemented by lowering the memcpy intrinsic to a series of SD-only
MCOPY pseudo-instructions which performs a memory copy using a given number
of registers. During SD->MI lowering, we lower MCOPY to LDM/STM. This is a
little unusual, but it avoids the need to encode register lists in the SD,
and we can take advantage of SD use lists to decide whether to use the _UPD
variant of the instructions.
Fixes PR9199.
Differential Revision: http://reviews.llvm.org/D9508
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238473 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
The first several times this was committed (e.g. r229831, r233055), it caused several buildbot failures.
Apparently the reason for most failures was both clang and gcc's inability to deal with large numbers (> 10K) of bitset constructor calls in tablegen-generated initializers of instruction info tables.
This should now be fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238192 91177308-0d34-0410-b5e6-96231b3b80d8
The buildbots are still not satisfied.
MIPS and ARM are failing (even though at least MIPS was expected to pass).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237245 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
The first two times this was committed (r229831, r233055), it caused several buildbot failures.
At least some of the ARM and MIPS ones were due to gcc/binutils issues, and should now be fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237234 91177308-0d34-0410-b5e6-96231b3b80d8
per-function subtarget.
Currently, code-gen passes the default or generic subtarget to the constructors
of MCInstPrinter subclasses (see LLVMTargetMachine::addPassesToEmitFile), which
enables some targets (AArch64, ARM, and X86) to change their instprinter's
behavior based on the subtarget feature bits. Since the backend can now use
different subtargets for each function, instprinter has to be changed to use the
per-function subtarget rather than the default subtarget.
This patch takes the first step towards enabling instprinter to change its
behavior based on the per-function subtarget. It adds a bit "PassSubtarget" to
AsmWriter which tells table-gen to pass a reference to MCSubtargetInfo to the
various print methods table-gen auto-generates.
I will follow up with changes to instprinters of AArch64, ARM, and X86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233411 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r233055.
It still causes buildbot failures (gcc running out of memory on several platforms, and a self-host failure on arm), although less than the previous time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233068 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
The first time this was committed (r229831), it caused several buildbot failures.
At least some of the ARM ones were due to gcc/binutils issues, and should now be fixed.
Differential Revision: http://reviews.llvm.org/D8542
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233055 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
Differential Revision: http://reviews.llvm.org/D7065
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229831 91177308-0d34-0410-b5e6-96231b3b80d8
Certain ARM instructions accept 32-bit immediate operands encoded as a 8-bit
integer value (0-255) and a 4-bit rotation (0-30, even). Current ARM assembly
syntax support in LLVM allows the decoded (32-bit) immediate to be specified
as a single immediate operand for such instructions:
mov r0, #4278190080
The ARMARM defines an extended assembly syntax allowing the encoding to be made
more explicit, as in:
mov r0, #255, #8 ; (same 32-bit value as above)
The behaviour of the two instructions can be different w.r.t flags, which is
documented under "Modified immediate constants" in ARMARM. This patch enables
support for this extended syntax at the MC layer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223113 91177308-0d34-0410-b5e6-96231b3b80d8
This instruction form is handled by different AsmOperands now, so the code is
completely dead (and wrong anyway).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219127 91177308-0d34-0410-b5e6-96231b3b80d8
This patch implements a few changes related to the Thumb2 M-class MSR instruction:
* better handling of unpredictable encodings,
* recognition of the _g and _nzcvqg variants by the asm parser only if the DSP
extension is available, preferred output of MSR APSR moves with the _<bits>
suffix for v7-M.
Patch by Petr Pavlu.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216874 91177308-0d34-0410-b5e6-96231b3b80d8
These are system-only instructions for CPUs with virtualization
extensions, allowing a hypervisor easy access to all of the various
different AArch32 registers.
rdar://problem/17861345
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215700 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we would always print the offset as decimal, regardless of
the formatting requested. Now we use the formatImm() helper so the value
is printed as the client (LLDB in the motivating example) requested.
Before:
ldr.w r8, [sp, #180] @ always
After:
ldr.w r8, [sp, #0xb4] @ when printing hex immediates
ldr.w r8, [sp, #0180] @ when printing decimal immediates
rdar://17237103
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210701 91177308-0d34-0410-b5e6-96231b3b80d8
Operands which involved label arithemetic would previously fail to parse. This
corrects that by adding the additional case for the shift operand validation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198735 91177308-0d34-0410-b5e6-96231b3b80d8
1. it should accept only 4-byte aligned addresses
2. the maximum offset should be 1020
3. it should be encoded with the offset scaled by two bits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185528 91177308-0d34-0410-b5e6-96231b3b80d8
In thumb1, NOP is a pseudo-instruction equivalent to mov r8, r8.
However the disassembler should not use this alias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184703 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes two previous issues:
- Negative offsets were not correctly disassembled
- The decoded opcodes were not the right one
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184180 91177308-0d34-0410-b5e6-96231b3b80d8
According to the ARM reference manual, constant offsets are mandatory for pre-indexed addressing modes.
The MC disassembler was not obeying this when the offset is 0.
It was producing instructions like: str r0, [r1]!.
Correct syntax is: str r0, [r1, #0]!.
This change modifies the dumping of operands so that the offset is always printed, regardless of its value, when pre-indexed addressing mode is used.
Patch by Mihail Popa <Mihail.Popa@arm.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179398 91177308-0d34-0410-b5e6-96231b3b80d8
The Printer will now print instructions with the correct alignment specifier syntax, like
vld1.8 {d16}, [r0:64]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175884 91177308-0d34-0410-b5e6-96231b3b80d8
This is for the lldb team so most of but not all of the values are
to be printed as hex with this option. Some small values like the
scale in an X86 address were requested to printed in decimal
without the leading 0x.
There may be some tweaks need to places that may still be in
decimal that they want in hex. Specially for arm. I made my best
guess. Any tweaks from here should be simple.
I also did the best I know now with help from the C++ gurus
creating the cleanest formatImm() utility function and containing
the changes. But if someone has a better idea to make something
cleaner I'm all ears and game for changing the implementation.
rdar://8109283
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169393 91177308-0d34-0410-b5e6-96231b3b80d8
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. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
This patch replaces the hard coded GPR pair [R0, R1] of
Intrinsic:arm_ldrexd and [R2, R3] of Intrinsic:arm_strexd with
even/odd GPRPair reg class.
Similar to the lowering of atomic_64 operation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168207 91177308-0d34-0410-b5e6-96231b3b80d8
When the operand is a plain immediate rather than a label, print it
as [pc, #imm] like we do for the Thumb2 wide encoding variant.
rdar://12154503
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166991 91177308-0d34-0410-b5e6-96231b3b80d8
and easier to read by adding a couple helper functions. Suggestion by
Chandler Carruth and seconded by Meador Inge!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166515 91177308-0d34-0410-b5e6-96231b3b80d8
Per the October 12, 2012 Proposal for annotated disassembly output sent out by
Jim Grosbach this set of changes implements this for X86 and arm. The llvm-mc
tool now has a -mdis option to produced the marked up disassembly and a couple
of small example test cases have been added.
rdar://11764962
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166445 91177308-0d34-0410-b5e6-96231b3b80d8
