When SelectionDAGISel transforms a node representing an inline asm
block, memory constraint information is not preserved. This can cause
constraints to be broken when a memory offset is of the form:
offset + frame index
when the frame is resolved.
By propagating the constraints all the way to the backend, targets can
enforce memory operands of inline assembly to conform to their constraints.
For MIPSR6, some instructions had their offsets reduced to 9 bits from
16 bits such as ll/sc. This becomes problematic when using inline assembly
to perform atomic operations, as an offset can generated that is too big to
encode in the instruction.
Reviewers: dsanders, vkalintris
Differential Review: https://reviews.llvm.org/D21615
llvm-svn: 275786
Summary:
It was recently discovered that, for Mips's SelectionDAGISel subclasses,
all optimization levels caused SelectionDAGISel to behave like -O2.
This change adds the necessary plumbing to initialize the optimization level.
Reviewers: andrew.w.kaylor
Subscribers: andrew.w.kaylor, sdardis, dean, llvm-commits, vradosavljevic, petarj, qcolombet, probinson, dsanders
Differential Revision: https://reviews.llvm.org/D14900
llvm-svn: 275410
Tail merge was making the assumption that a layout successor or
predecessor was always a cfg successor/predecessor. Remove that
assumption. Changes to tests are necessary because the errant cfg edges
were preventing optimizations.
llvm-svn: 273700
Summary:
The backend has no reason to behave like a driver and should generally do
as it's told (and error out if it can't) instead of trying to figure out
what the API user meant. The default ABI is still derived from the arch
component as a concession to backwards compatibility.
API-users that previously passed an explicit CPU and a triple that was
inconsistent with the CPU (e.g. mips-linux-gnu and mips64r2) may get a
different ABI to what they got before. However, it's expected that there
are no such users on the basis that CodeGen has been asserting that the
triple is consistent with the selected ABI for several releases. API-users
that were consistent or passed '' or 'generic' as the CPU will see no
difference.
Reviewers: sdardis, rafael
Subscribers: rafael, dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D21466
llvm-svn: 273557
Summary:
JR is an alias of JALR with $rd=0 in the R6 ISA. Also, this fixes recursive
builds in MIPS32R6.
Reviewers: dsanders, sdardis
Subscribers: jfb, dschuff, dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D21370
llvm-svn: 273085
Summary:
[ls][bh] and [ls][bh]u cannot use sp-relative addresses and must therefore
lower frameindex nodes such that there is a copy to a CPU16Regs register. This
is now done consistently using a separate addressing mode that does not
permit frameindex nodes.
As part of this I've had to remove an optimization that reduced the number of
instructions needed to work around the lack of sp-relative addresses on [ls][bh]
and [ls][bh]u. This optimization used one of the eight CPU16Regs registers as
a copy of the stack pointer and it's implementation was the root cause of many
of the register vs register class mismatches.
lw/sw can use sp-relative addresses but we ought to ensure that we use the
correct version of lw/sw internally for things like IAS. This is not currently
the case and this change does not fix this. However, this change does clean it
up sufficiently well to fix the machine verifier failures.
Also removed irrelevant functions from stchar.ll.
Reviewers: sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D21062
llvm-svn: 272882
Summary:
The Mips implementation only covers the feature bits described by the ELF
e_flags so far. Mips stores additional feature bits such as MSA in the
.MIPS.abiflags section.
Also fixed a small bug this revealed where microMIPS wouldn't add the
EF_MIPS_MICROMIPS flag when using -filetype=obj.
Reviewers: echristo, rafael
Subscribers: rafael, mehdi_amini, dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D21125
llvm-svn: 272880
Instead of always using addu to adjust the stack pointer when the
size out is of the range of an addiu instruction, use subu so that
a smaller constant can be generated.
This can give savings of ~3 instructions whenever a function has a
a stack frame whose size is out of range of an addiu instruction.
This change may break some naive stack unwinders.
Partially resolves PR/26291.
Thanks to David Chisnall for reporting the issue.
Reviewers: dsanders, vkalintiris
Differential Review: http://reviews.llvm.org/D21321
llvm-svn: 272666
PR27458 highlights that the MIPS backend does not have well formed
MIR for atomic operations (among other errors).
This patch adds expands and corrects the LL/SC descriptions and uses
for MIPS(64).
Reviewers: dsanders, vkalintiris
Differential Review: http://reviews.llvm.org/D19719
llvm-svn: 272655
Itineraries for some pre MIPSR6 and EVA instructions. Some pseudo expanded
instructions are marked as having no scheduling info.
Reviewers: dsanders, vkalintiris
Differential Review: http://reviews.llvm.org/D20418
llvm-svn: 272648
Summary:
The machine verifier reports 'Explicit operand marked as def' when it is
manually specified even though it agrees with the operand info.
Reviewers: sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D21065
llvm-svn: 272646
Summary:
N32 support will follow in a later patch since the symbol version of 'la'
incorrectly believes N32 to have 64-bit pointers and rejects it early.
This fixes the three incorrectly expanded 'la' macros found in bionic.
Reviewers: sdardis
Subscribers: dsanders, llvm-commits, sdardis
Differential Revision: http://reviews.llvm.org/D20820
llvm-svn: 271644
beqc and bnec cannot have $rs == $rt. Inhibit compact branch creation
if that would occur.
Reviewers: vkalintiris, dsanders
Differential Revision: http://reviews.llvm.org/D20624
llvm-svn: 271260
Restrict the creation of compact branches so that they meet the ISA encoding
requirements. Notably do not permit $zero to be used as a operand for compact
branches and ensure that some other branches fulfil the requirement that
rs != rt.
Fixup cases where $rs > $rt for bnec and beqc.
Reviewers: dsanders, vkalintiris
Differential Review: http://reviews.llvm.org/D20284
llvm-svn: 269893
This patch adds the commandline option -mips-compact-branches={never,optimal,always),
which controls how LLVM generates compact branches for MIPS targets. By
default, the compact branch policy is 'optimal' where LLVM will (hopefully)
pick the optimal branch for any situation. The 'never' policy will disable
the generation of compact branches and 'always' will generate compact branches
wherever possible.
Reviewers: dsanders
Differential Review: http://reviews.llvm.org/D20167
llvm-svn: 269753
Summary:
The MIPS IAS can now pass 'ninja check-all', recurse, build a bootable linux
kernel, and pass a variety of LNT testing.
Unfortunately we can't enable it by default for 64-bit targets yet since the N32
ABI is still very buggy and this also means we can't enable it for N64 either
because we can't distinguish between N32 and N64 in the relevant code.
Reviewers: vkalintiris
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D18759
Differential Revision: http://reviews.llvm.org/D18761
llvm-svn: 269560
Summary:
Previously, it returned the GPR16MMRegClass for all instructions which was
incorrect for instructions like lwsp/lwgp and unnecesarily restricted the
permitted registers for instructions like lw32.
This fixes quite a few of the -verify-machineinstrs errors reported in PR27458.
I've only added -verify-machineinstrs to one test in this change since I
understand there is a plan to enable the verifier by default.
Reviewers: hvarga, zbuljan, zoran.jovanovic, sdardis
Subscribers: dsanders, llvm-commits, sdardis
Differential Revision: http://reviews.llvm.org/D19873
llvm-svn: 268918
Summary:
This stops it misidentifying unconditional branches as conditional branches
which fixes a -verify-machineinstrs error about exiting a function via fall through.
Reviewers: sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D19864
llvm-svn: 268731
Summary:
It's always zero for SelectionDAG and is never read by the MIPS backend so
do the same for FastISel.
Reviewers: sdardis
Subscribers: dsanders, llvm-commits, sdardis
Differential Revision: http://reviews.llvm.org/D19863
llvm-svn: 268386
Correct trivial error. One of the failing tests from PR/27458.
Reviewers: dsanders, vkalintiris, mcrosier
Differential Review: http://reviews.llvm.org/D19726
llvm-svn: 268053
Currently Mips::emitAtomicBinaryPartword() does not properly respect the
width of pointers. For MIPS64 this causes the memory address that the ll/sc
sequence uses to be truncated. At runtime this causes a segmentation fault.
This can be fixed by applying similar changes as r266204, so that a full 64bit
pointer is loaded.
Reviewers: dsanders
Differential Review: http://reviews.llvm.org/D19651
llvm-svn: 267900
When targetting MIPS64R6 some of the patterns for select were guarded by a
broken predicate. The predicate was supposed to test if a constant value
could fit in a 16 bit zero-extended field. Instead the value was tested to
fit in a 16 bit sign-extended field. For negative constants of native word
width this resulted in wrong code generation.
Reviewers: vkalintiris, dsanders
Differential Review: http://reviews.llvm.org/D19378
llvm-svn: 267151
Alias 'jic $reg, 0' to 'jrc $reg' and 'jialc $reg, 0' to 'jalrc $reg' like
binutils.
This patch was previous committed as r266055 as seemed to have caused some spurious
test failures. They did not reappear after further local testing.
llvm-svn: 266301
Summary:
The only difference between the removed tests and the pre-existing
ones, is the materialization of the zero constant, which shouldn't
matter for these cases.
Reviewers: dsanders, sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: http://reviews.llvm.org/D18693
llvm-svn: 266285
Simon Dardis