The 2nd loop calculates spill costs but reports free registers as cost
0 anyway, so there is little benefit from having a separate early
loop.
Surprisingly this is not NFC, as many register are marked regDisabled
so the first loop often picks up later registers unnecessarily instead
of the first one available in the allocation order...
Patch by Matthias Braun
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356499 91177308-0d34-0410-b5e6-96231b3b80d8
Part of the effort to refactoring frame pointer code generation. We used
to use two function attributes "no-frame-pointer-elim" and
"no-frame-pointer-elim-non-leaf" to represent three kinds of frame
pointer usage: (all) frames use frame pointer, (non-leaf) frames use
frame pointer, (none) frame use frame pointer. This CL makes the idea
explicit by using only one enum function attribute "frame-pointer"
Option "-frame-pointer=" replaces "-disable-fp-elim" for tools such as
llc.
"no-frame-pointer-elim" and "no-frame-pointer-elim-non-leaf" are still
supported for easy migration to "frame-pointer".
tests are mostly updated with
// replace command line args ‘-disable-fp-elim=false’ with ‘-frame-pointer=none’
grep -iIrnl '\-disable-fp-elim=false' * | xargs sed -i '' -e "s/-disable-fp-elim=false/-frame-pointer=none/g"
// replace command line args ‘-disable-fp-elim’ with ‘-frame-pointer=all’
grep -iIrnl '\-disable-fp-elim' * | xargs sed -i '' -e "s/-disable-fp-elim/-frame-pointer=all/g"
Patch by Yuanfang Chen (tabloid.adroit)!
Differential Revision: https://reviews.llvm.org/D56351
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351049 91177308-0d34-0410-b5e6-96231b3b80d8
- Relex hard coded registers and stack frame sizes
- Some test cleanups
- Change phi-dbg.ll to match on mir output after phi elimination instead
of going through the whole codegen pipeline.
This is in preparation for https://reviews.llvm.org/D52010
I'm committing all the test changes upfront that work before and after
independently.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345532 91177308-0d34-0410-b5e6-96231b3b80d8
The r337288 tried to fix result of icmp i1 when its input is not sanitized
by falling back to DagISel. While it now produces the correct result for
bit 0, the other bits can still hold arbitrary value which is not supported
by MipsFastISel branch lowering. This patch fixes the issue by falling back
to DagISel in this case.
Patch by Dragan Mladjenovic.
Differential Revision: https://reviews.llvm.org/D52045
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342884 91177308-0d34-0410-b5e6-96231b3b80d8
This change fixes the issue that arises when we duplicate condition from
the predecessor block. If the condition's arguments are not considered alive
across the blocks, fast regalloc gets confused and starts generating reloads
from the slots that have never been spilled to. This change also leads to
smaller code given that, unlike on architectures with condition codes, on
Mips we can branch directly on register value, thus we gain nothing by
duplication.
Patch by Dragan Mladjenovic.
Differential Revision: https://reviews.llvm.org/D48642
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336084 91177308-0d34-0410-b5e6-96231b3b80d8
This is causing compilation timeouts on code with long sequences of
local values and calls (i.e. foo(1); foo(2); foo(3); ...). It turns out
that code coverage instrumentation is a great way to create sequences
like this, which how our users ran into the issue in practice.
Intel has a tool that detects these kinds of non-linear compile time
issues, and Andy Kaylor reported it as PR37010.
The current sinking code scans the whole basic block once per local
value sink, which happens before emitting each call. In theory, local
values should only be introduced to be used by instructions between the
current flush point and the last flush point, so we should only need to
scan those instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329822 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Local values are constants, global addresses, and stack addresses that
can't be folded into the instruction that uses them. For example, when
storing the address of a global variable into memory, we need to
materialize that address into a register.
FastISel doesn't want to materialize any given local value more than
once, so it generates all local value materialization code at
EmitStartPt, which always dominates the current insertion point. This
allows it to maintain a map of local value registers, and it knows that
the local value area will always dominate the current insertion point.
The downside is that local value instructions are always emitted without
a source location. This is done to prevent jumpy line tables, but it
means that the local value area will be considered part of the previous
statement. Consider this C code:
call1(); // line 1
++global; // line 2
++global; // line 3
call2(&global, &local); // line 4
Today we end up with assembly and line tables like this:
.loc 1 1
callq call1
leaq global(%rip), %rdi
leaq local(%rsp), %rsi
.loc 1 2
addq $1, global(%rip)
.loc 1 3
addq $1, global(%rip)
.loc 1 4
callq call2
The LEA instructions in the local value area have no source location and
are treated as being on line 1. Stepping through the code in a debugger
and correlating it with the assembly won't make much sense, because
these materializations are only required for line 4.
This is actually problematic for the VS debugger "set next statement"
feature, which effectively assumes that there are no registers live
across statement boundaries. By sinking the local value code into the
statement and fixing up the source location, we can make that feature
work. This was filed as https://bugs.llvm.org/show_bug.cgi?id=35975 and
https://crbug.com/793819.
This change is obviously not enough to make this feature work reliably
in all cases, but I felt that it was worth doing anyway because it
usually generates smaller, more comprehensible -O0 code. I measured a
0.12% regression in code generation time with LLC on the sqlite3
amalgamation, so I think this is worth doing.
There are some special cases worth calling out in the commit message:
1. local values materialized for phis
2. local values used by no-op casts
3. dead local value code
Local values can be materialized for phis, and this does not show up as
a vreg use in MachineRegisterInfo. In this case, if there are no other
uses, this patch sinks the value to the first terminator, EH label, or
the end of the BB if nothing else exists.
Local values may also be used by no-op casts, which adds the register to
the RegFixups table. Without reversing the RegFixups map direction, we
don't have enough information to sink these instructions.
Lastly, if the local value register has no other uses, we can delete it.
This comes up when fastisel tries two instruction selection approaches
and the first materializes the value but fails and the second succeeds
without using the local value.
Reviewers: aprantl, dblaikie, qcolombet, MatzeB, vsk, echristo
Subscribers: dotdash, chandlerc, hans, sdardis, amccarth, javed.absar, zturner, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D43093
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327581 91177308-0d34-0410-b5e6-96231b3b80d8
In the long-term, we want to replace statistics with something
finer-grained that lets us gather per-function data.
Remarks are that replacement.
Create an ORE instance in SelectionDAGISel, and pass it to
SelectionDAG.
SelectionDAG was used so that we can emit remarks from all
SelectionDAG-related code, including TargetLowering and DAGCombiner.
This isn't used in the current patch but Adam tells me he's interested
for the fp-contract combines.
Use the ORE instance to emit FastISel failures as remarks (instead of
the mix of dbgs() dumps and statistics that we currently have).
Eventually, we want to have an API that tells us whether remarks are
enabled (http://llvm.org/PR32352) so that we don't emit expensive
remarks (in this case, dumping IR) when it's not needed. For now, use
'isEnabled' as a crude replacement.
This does mean that the replacement for '-fast-isel-verbose' is now
'-pass-remarks-missed=isel'. Additionally, clang users also need to
enable remark diagnostics, using '-Rpass-missed=isel'.
This also removes '-fast-isel-verbose2': there are no static statistics
that we want to only enable in asserts builds, so we can always use
the remarks regardless of the build type.
Differential Revision: https://reviews.llvm.org/D31405
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299093 91177308-0d34-0410-b5e6-96231b3b80d8
MipsFastISel uses a a class to represent addresses with a signed member
to represent the offset. MipsFastISel::emitStore, emitLoad and computeAddress
all treated the offset as being positive. In cases where the offset was
actually negative and a frame pointer was used, this would cause the constant
synthesis routine to crash as it would generate an unexpected instruction
sequence when frame indexes are replaced.
Reviewers: vkalintiris
Differential Revision: https://reviews.llvm.org/D26192
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287099 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Instead of instantiating the MipsFastISel class and checking if the
target is supported in the overriden methods, we should perform that
check before creating the class. This allows us to enable FastISel *only*
for targets that truly support it, ie. MIPS32 to MIPS32R5.
Reviewers: sdardis
Subscribers: ehostunreach, llvm-commits
Differential Revision: https://reviews.llvm.org/D24824
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284475 91177308-0d34-0410-b5e6-96231b3b80d8
Treat soft-float as unsupported for fast-isel. Additionally, ensure we check
that lowering f32 arguments also considers the case of soft-float mode.
Reviewers: ehostunreach, vkalintiris, zoran.jovanovic
Differential Review: https://reviews.llvm.org/D24505
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283209 91177308-0d34-0410-b5e6-96231b3b80d8
LLVM PR/29052 highlighted that FastISel for MIPS attempted to lower
arguments assuming that it was using the paired 32bit registers to
perform operations for f64. This mode of operation is not supported
for MIPSR6.
This patch resolves the reported issue by adding additional checks
for unsupported floating point unit configuration.
Thanks to mike.k for reporting this issue!
Reviewers: seanbruno, vkalintiris
Differential Review: https://reviews.llvm.org/D23795
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280706 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Allocating an AFGR64 shadows two GPR32's instead of just one.
This fixes an LNT regression detected by our internal buildbots.
Reviewers: sdardis
Subscribers: dsanders, sdardis, llvm-commits
Differential Revision: https://reviews.llvm.org/D23012
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277348 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Implements fastLowerArguments() to avoid the need to fall back on
SelectionDAG for 0-4 argument functions that don't do tricky things like
passing double in a pair of i32's.
This allows us to move all except one test to -fast-isel-abort=3. The
remaining one has function prototypes of the form 'i32 (i32, double, double)'
which requires floats to be passed in GPR's.
The previous commit had an uninitialized variable that caused the incoming
argument region to have undefined size. This has been fixed.
Reviewers: sdardis
Subscribers: dsanders, llvm-commits, sdardis
Differential Revision: https://reviews.llvm.org/D22680
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277136 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Implements fastLowerArguments() to avoid the need to fall back on
SelectionDAG for 0-4 argument functions that don't do tricky things like
passing double in a pair of i32's.
This allows us to move all except one test to -fast-isel-abort=3. The
remaining one has function prototypes of the form 'i32 (i32, double, double)'
which requires floats to be passed in GPR's.
Reviewers: sdardis
Subscribers: dsanders, llvm-commits, sdardis
Differential Revision: https://reviews.llvm.org/D22680
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276982 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273557 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272880 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268386 91177308-0d34-0410-b5e6-96231b3b80d8
Author: milena.vujosevic.janicic
Reviewers: dsanders
FastIsel is not supported for microMIPS, thus it needs to be disabled.
Test micromips-zero-mat-uses.ll is deleted since the tested sequence of instructions is not generated for microMIPS without FastISel.
Differential Revision: http://reviews.llvm.org/D15892
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@259039 91177308-0d34-0410-b5e6-96231b3b80d8
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
These intrinsics currently have an explicit alignment argument which is
required to be a constant integer. It represents the alignment of the
source and dest, and so must be the minimum of those.
This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments. The alignment
argument itself is removed.
There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe. For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.
For example, code which used to read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)
For out of tree owners, I was able to strip alignment from calls using sed by replacing:
(call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
$1i1 false)
and similarly for memmove and memcpy.
I then added back in alignment to test cases which needed it.
A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.
In IRBuilder itself, a new argument was added. Instead of calling:
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)
There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool. This is to prevent isVolatile here from passing its default
parameter to the source alignment.
Note, changes in future can now be made to codegen. I didn't change anything here, but this
change should enable better memcpy code sequences.
Reviewed by Hal Finkel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253511 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This hidden option would disable code generation through FastISel by
default. It was removed from the available options and from the
Fast-ISel tests that required it in order to run the tests.
Reviewers: dsanders
Subscribers: qcolombet, llvm-commits
Differential Revision: http://reviews.llvm.org/D11610
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243638 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Previously, we would sign-extend non-boolean negative constants and
zero-extend otherwise. This was problematic for PHI instructions with
negative values that had a type with bitwidth less than that of the
register used for materialization.
More specifically, ComputePHILiveOutRegInfo() assumes the constants
present in a PHI node are zero extended in their container and
afterwards deduces the known bits.
For example, previously we would materialize an i16 -4 with the
following instruction:
addiu $r, $zero, -4
The register would end-up with the 32-bit 2's complement representation
of -4. However, ComputePHILiveOutRegInfo() would generate a constant
with the upper 16-bits set to zero. The SelectionDAG builder would use
that information to generate an AssertZero node that would remove any
subsequent trunc & zero_extend nodes.
In theory, we should modify ComputePHILiveOutRegInfo() to consult
target-specific hooks about the way they prefer to materialize the
given constants. However, git-blame reports that this specific code
has not been touched since 2011 and it seems to be working well for every
target so far.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11592
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243636 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently, we support only the MIPS O32 ABI calling convention for call
lowering. With this change we avoid using the O32 calling convetion for
lowering calls marked as using the fast calling convention.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11515
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243485 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Generate correct code for the select instruction by zero-extending
it's boolean/condition operand to GPR-width. This is necessary because
the conditional-move instructions operate on the whole register.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11506
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243469 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Implement bswap intrinsic for MIPS FastISel. It's very different for misp32 r1/r2 .
Based on a patch by Reed Kotler.
Test Plan:
bswap1.ll
test-suite
Reviewers: dsanders, rkotler
Subscribers: llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D7219
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238760 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Implement the intrinsics memset, memcopy and memmove in MIPS FastISel.
Make some needed infrastructure fixes so that this can work.
Based on a patch by Reed Kotler.
Test Plan:
memtest1.ll
The patch passes test-suite for mips32 r1/r2 and at O0/O2
Reviewers: rkotler, dsanders
Subscribers: llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D7158
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238759 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Implement the LLVM assembly urem/srem and sdiv/udiv instructions in MIPS FastISel.
Based on a patch by Reed Kotler.
Test Plan:
srem1.ll
div1.ll
test-suite at O0/O2 for mips32 r1/r2
Reviewers: dsanders, rkotler
Subscribers: llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D7028
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238757 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Implement the LLVM IR select statement for MIPS FastISelsel.
Based on a patch by Reed Kotler.
Test Plan:
"Make check" test included now.
Passes test-suite at O2/O0 mips32 r1/r2.
Reviewers: dsanders, rkotler
Subscribers: llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D6774
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238756 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The contents of the HI/LO registers are unpredictable after the execution of
the MUL instruction. In addition to implicitly defining these registers in the
MUL instruction definition, we have to mark those registers as dead too.
Without this the fast register allocator is running out of registers when the
MUL instruction is followed by another one that tries to allocate the AC0
register.
Based on a patch by Reed Kotler.
Reviewers: dsanders, rkotler
Subscribers: llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D9825
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238755 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Allow calls with non legal integer types based on i8 and i16 to be processed by mips fast-isel.
Based on a patch by Reed Kotler.
Test Plan:
"Make check" test forthcoming.
Test-suite passes at O0/O2 and with mips32 r1/r2
Reviewers: rkotler, dsanders
Subscribers: llvm-commits, rfuhler
Differential Revision: http://reviews.llvm.org/D6770
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237121 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Try to compute addresses when the offset from a memory location is a constant
expression.
Based on a patch by Reed Kotler.
Test Plan:
Passes test-suite for -O0/O2 and mips 32 r1/r2
Reviewers: rkotler, dsanders
Subscribers: llvm-commits, aemerson, rfuhler
Differential Revision: http://reviews.llvm.org/D6767
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237117 91177308-0d34-0410-b5e6-96231b3b80d8
This reapplies r235194, which was reverted in r235495 because it was causing a
failure in our out-of-tree buildbots for MIPS. With the sign-extension patch
in r235718, this patch doesn't cause any problem any more.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235878 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r235194. It was causing a failure in FastISel buildbots
due to sign-extension issues.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235495 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Implement the method FastMaterializeAlloca in Mips fast-isel
Based on a patch by Reed Kotler.
Test Plan:
Passes test-suite at O0/O2 for mips32 r1/r2
fastalloca.ll
Reviewers: dsanders, rkotler
Subscribers: rfuhler, llvm-commits
Differential Revision: http://reviews.llvm.org/D6742
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235213 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Add shift operators implementation to fast-isel for Mips. These are shift ops
for non legal forms, i.e. i8 and i16.
Based on a patch by Reed Kotler.
Test Plan:
Reviewers: dsanders
Subscribers: echristo, rfuhler, llvm-commits
Differential Revision: http://reviews.llvm.org/D6726
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235194 91177308-0d34-0410-b5e6-96231b3b80d8
Fast isel used to zero extends immediates to 64 bits. This normally goes
unnoticed because the value is truncated to 32 bits for output.
Two cases were it is noticed:
* We fail to use smaller encodings.
* If the original constant was smaller than i32.
In the tests using i1 constants, codegen would change to use -1, which is fine
(and matches what regular isel does) since only the lowest bit is then used.
Instead, this patch then changes the ir to use i8 constants, which looks more
like what clang produces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234249 91177308-0d34-0410-b5e6-96231b3b80d8
Matt Arsenault