For the following description, consider the following basic block graph:
b1 ───┐┌──── b2
││
││
▼▼
b3
For register allocator transitions between basic blocks, there are two
key passes (significant paraphrasing):
First, each basic block is visited in some predetermined visit order.
This is the core visitOrder range loop in regAllocState.regalloc. The
specific ordering heuristics aren't important here, except that the
order guarantees that when visiting a basic block at least one of its
predecessors has already been visited.
Upon visiting a basic block, that block sets its expected starting
register state (regAllocState.startRegs) based on the ending register
state (regAlloc.State.endRegs) of one of its predecessors. (How it
chooses which predecessor to use is not important here.)
From that starting state, registers are assigned for all values in the
block, ultimately resulting in some ending register state.
After all blocks have been visited, the shuffle pass
(regAllocState.shuffle) ensures that for each edge, endRegs of the
predecessor == startRegs of the successor. That is, it makes sure that
the startRegs assumptions actually hold true for each edge. It does this
by adding moves to the end of the predecessor block to place values in
the expected register for the successor block. These may be moves from
other registers, or from memory if the value is spilled.
Now on to the actual problem:
Assume that b1 places some value v1 into register R10, and thus ends
with endRegs containing R10 = v1.
When b3 is visited, it selects b1 as its model predecessor and sets
startRegs with R10 = v1.
b2 does not have v1 in R10, so later in the shuffle pass, we will add a
move of v1 into R10 to the end of b2 to ensure it is available for b3.
This is all perfectly fine and exactly how things should work.
Now suppose that b3 does not use v1. It does need to use some other
value v2, which is not currently in a register. When assigning v2 to a
register, it finds all registers are already in use and it needs to dump
a value. Ultimately, it decides to dump v1 from R10 and replace it with
v2.
This is fine, but it has downstream effects on shuffle in b2. b3's
startRegs still state that R10 = v1, so b2 will add a move to R10 even
though b3 will unconditionally overwrite it. i.e., the move at the end
of b2 is completely useless and can result in code like:
// end of b2
MOV n(SP), R10 // R10 = v1 <-- useless
// start of b3
MOV m(SP), R10 // R10 = v2
This is precisely what happened in #58298.
This CL addresses this problem by dropping registers from startRegs if
they are never used in the basic block prior to getting dumped. This
allows the shuffle pass to avoid placing those useless values into the
register.
There is a significant limitation to this CL, which is that it only
impacts the immediate predecessors of an overwriting block. We can
discuss this by zooming out a bit on the previous graph:
b4 ───┐┌──── b5
││
││
▼▼
b1 ───┐┌──── b2
││
││
▼▼
b3
Here we have the same graph, except we can see the two predecessors of
b1.
Now suppose that rather than b1 assigning R10 = v1 as above, the
assignment is done in b4. b1 has startRegs R10 = v1, doesn't use the
value at all, and simply passes it through to endRegs R10 = v1.
Now the shuffle pass will require both b2 and b5 to add a move to
assigned R10 = v1, because that is specified in their successor
startRegs.
With this CL, b3 drops R10 = v1 from startRegs, but there is no
backwards propagation, so b1 still has R10 = v1 in startRegs, and b5
still needs to add a useless move.
Extending this CL with such propagation may significantly increase the
number of useless moves we can remove, though it will add complexity to
maintenance and could potentially impact build performance depending on
how efficiently we could implement the propagation (something I haven't
considered carefully).
As-is, this optimization does not impact much code. In bent .text size
geomean is -0.02%. In the container/heap test binary, 18 of ~2500
functions are impacted by this CL. Bent and sweet do not show a
noticeable performance impact one way or another, however #58298 does
show a case where this can have impact if the useless instructions end
up in the hot path of a tight loop.
For #58298.
Change-Id: I2fcef37c955159d068fa0725f995a1848add8a5f
Reviewed-on: https://go-review.googlesource.com/c/go/+/471158
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
When we're compiling a resultInArg0 op, we need to clobber the
register containing the input value. So we first make a register copy
of the input value. We can then clobber either of the two registers
the value is in and still have the original input value in a register
for future uses.
Before this CL, we always clobbered the original, not the copy.
But that's not always the right decision - if the original is already
in a specific register that it needs to be in later (typically, a
return value register), clobber the copy instead.
This optimization can remove a mov instruction. It saves 1376 bytes
of instructions in cmd/go.
Redo of CL 460656, reverted at CL 463475, with a fix for s390x.
The new code just ensures that the copied value is in a register
which is a valid input register for the instruction.
Change-Id: Id570b8a60a6d2da9090de80a90b6bb0266e9e38a
Reviewed-on: https://go-review.googlesource.com/c/go/+/463221
Auto-Submit: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
This reverts CL 460656
Reason for revert: This breaks s390x.
Change-Id: I8fada14fabc90593b8033ed11188c04963d2da75
Reviewed-on: https://go-review.googlesource.com/c/go/+/463475
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
When we're compiling a resultInArg0 op, we need to clobber the
register containing the input value. So we first make a register copy
of the input value. We can then clobber either of the two registers
the value is in and still have the original input value in a register
for future uses.
Before this CL, we always clobbered the original, not the copy.
But that's not always the right decision - if the original is already
in a specific register that it needs to be in later (typically, a
return value register), clobber the copy instead.
This optimization can remove a mov instruction. It saves 1376 bytes
of instructions in cmd/go.
Change-Id: I162870c84b9a180da6715bb24c296a902974fed3
Reviewed-on: https://go-review.googlesource.com/c/go/+/460656
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
We need to avoid nospill registers at this point in regalloc.
Make sure that we don't restrict our register set to avoid registers
desired by other instructions, if the resulting set includes only
nospill registers.
Fixes#57846
Change-Id: I05478e4513c484755dc2e8621d73dac868e45a27
Reviewed-on: https://go-review.googlesource.com/c/go/+/461685
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Temporary registers are sometimes needed for an architecture backend
which needs to use several machine instructions to implement a single
SSA instruction.
Mark such instructions so that regalloc can reserve the temporary register
for it. That way we don't have to reserve a fixed register like we do now.
Convert the temp-register-using instructions on amd64 to use this
new mechanism. Other archs can follow as needed.
Change-Id: I1d0c8588afdad5cd18b4398eb5a0f755be5dead7
Reviewed-on: https://go-review.googlesource.com/c/go/+/398556
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
We kind of have this mechanism already, just normalizing it and
using it in a bunch of places. Previously a bunch of places cached
slices only for the duration of a single function compilation. Now
we can reuse slices across a whole compiler run.
Use a sync.Pool of powers-of-two sizes. This lets us use not
too much memory, and avoid holding onto memory we're no longer
using when a GC happens.
There's a few different types we need, so generate the code for it.
Generics would be useful here, but we can't use generics in the
compiler because of bootstrapping.
Change-Id: I6cf37e7b7b2e802882aaa723a0b29770511ccd82
Reviewed-on: https://go-review.googlesource.com/c/go/+/444820
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Make them a separate type, so the normal sparse maps don't
need the extra storage.
Change-Id: I3a0219487c35ea63723499723b0c742e321d97c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/444819
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
The gen folder was renamed to _gen in CL 435472, but references in code
and docs were not updated. This updates the references.
Change-Id: Ibadc0cdcb5bed145c3257b58465a8df370487ae5
Reviewed-on: https://go-review.googlesource.com/c/go/+/444355
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
This fixes two independent problems:
We normally propagate desired registers backwards through opcodes that
are marked resultInArg0. Unfortunately for the desired register
computation, ADDQconst is not marked as resultInArg0. This is because
the amd64 backend can write it out as LEAQ instead if the input and
output registers don't match. For desired register purposes, we want
to treat ADDQconst as resultInArg0, so that we get an ADDQ instead of
a LEAQ if we can.
Desired registers don't currently work for tuple-generating opcodes.
Declare that the desired register applies to the first element of the
tuple, and propagate the desired register back through Select0.
Noticed when fixing #51964
Change-Id: I83346b988882cd58c2d7e7e5b419a2b9a244ab66
Reviewed-on: https://go-review.googlesource.com/c/go/+/396035
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
This provides the runtime glue (_rt0_riscv64_linux_lib) for c-archive and c-shared
support, along with enabling both of these buildmodes on linux/riscv64.
Both misc/cgo/testcarchive and misc/cgo/testcshared now pass on this platform.
Fixes#47100
Change-Id: I7ad75b23ae1d592dbac60d15bba557668287711f
Reviewed-on: https://go-review.googlesource.com/c/go/+/334872
Trust: Joel Sing <joel@sing.id.au>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
When doing a tail call the link register is live as the callee
will directly return to the caller (of the function that does the
tail call). Don't allocate or clobber the link register.
Fixes#49032.
Change-Id: I2d60f2354e5b6c14aa285c8983a9786687b90223
Reviewed-on: https://go-review.googlesource.com/c/go/+/358435
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
It's only used in two places:
- The one in regalloc.go can be replaced with v.resetArgs()
- The one in rewrite.go can be open coded
and can cause wrong usage like the bug that CL 358117 fixed.
Change-Id: I125baf237db159d056fe4b1c73072331eea4d06a
Reviewed-on: https://go-review.googlesource.com/c/go/+/357965
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Also tweak comment for the arm64 case.
Change-Id: I073405bd2acf901dcaaf33a034a84b6a09dd4a83
Reviewed-on: https://go-review.googlesource.com/c/go/+/334869
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Tweak the register allocator to maintain the invariant that
OpArg{Int,Float}Reg values are placed together at the start of the
entry block, before any other non-pseudo-op values. Without this
change, when the register allocator adds spills we can wind up with an
interleaving of OpArg*Reg and stores, which complicates debug location
analysis.
Updates #40724.
Change-Id: Icf30dd814a9e25263ecbea2e48feb840a6e7f2bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/322630
Trust: Than McIntosh <thanm@google.com>
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Reviewed-by: Cherry Mui <cherryyz@google.com>
In the register allocator, if possible, we allocate a value to its
desired register (the ideal register for its next use). In some
cases the desired register does not satisfies the value's output
register mask. We should not use the register in this case.
In the following example, v33 is going to be returned as a
function result, so it is allocated to its desired register AX.
However, its Op cannot use AX as output, causing miscompilation.
v33 = CMOVQEQF <int> v24 v28 v29 : AX (~R0[int])
v35 = MakeResult <int,int,mem> v33 v26 v18
Ret v35
Change-Id: Id0f4f27c4b233ee297e83077e3c8494fe193e664
Reviewed-on: https://go-review.googlesource.com/c/go/+/314630
Trust: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: Than McIntosh <thanm@google.com>
Currently, if we have AX=a and BX=b, and we want to make a call
F(1, a, b), to move arguments into the desired registers it emits
MOVQ AX, CX
MOVL $1, AX // AX=1
MOVQ BX, DX
MOVQ CX, BX // BX=a
MOVQ DX, CX // CX=b
This has a few redundant moves.
This is because we process inputs in order. First, allocate 1 to
AX, which kicks out a (in AX) to CX (a free register at the
moment). Then, allocate a to BX, which kicks out b (in BX) to DX.
Finally, put b to CX.
Notice that if we start with allocating CX=b, then BX=a, AX=1,
we will not have redundant moves. This CL reduces redundant moves
by allocating them in different order: First, for inpouts that are
already in place, keep them there. Then allocate free registers.
Then everything else.
before after
cmd/compile binary size 23703888 23609680
text size 8565899 8533291
(with regabiargs enabled.)
Change-Id: I69e1bdf745f2c90bb791f6d7c45b37384af1e874
Reviewed-on: https://go-review.googlesource.com/c/go/+/311371
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
The go/build package needs access to this configuration,
so move it into a new package available to the standard library.
Change-Id: I868a94148b52350c76116451f4ad9191246adcff
Reviewed-on: https://go-review.googlesource.com/c/go/+/310731
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>
When -clobberdeadreg flag is set, the compiler inserts code that
clobbers integer registers at call sites. This may be helpful for
debugging register ABI.
Only implemented on AMD64 for now.
Change-Id: Ia203d3f891c30fd95d0103489056fe01d63a2899
Reviewed-on: https://go-review.googlesource.com/c/go/+/302809
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: David Chase <drchase@google.com>
This moves all remaining GOEXPERIMENT flags into the objabi.Experiment
struct, drops the "_enabled" from their name, and makes them all bool
typed.
We also drop DebugFlags.Fieldtrack because the previous CL shifted the
one test that used it to use GOEXPERIMENT instead.
Change-Id: I3406fe62b1c300bb4caeaffa6ca5ce56a70497fe
Reviewed-on: https://go-review.googlesource.com/c/go/+/302389
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
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Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The register allocator has a special case that doesn't allocate
LR on ARMv5. This was necessary when softfloat expansion was done
by the assembler. Now softfloat calls are inserted by SSA, so it
works as normal. Remove this special case.
Change-Id: I5502f07597f4d4b675dc16b6b0d7cb47e1e8974b
Reviewed-on: https://go-review.googlesource.com/c/go/+/301792
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
at least for ints and strings
includes simple test
For #40724.
Change-Id: Ib8484e5b957b08f961574a67cfd93d3d26551558
Reviewed-on: https://go-review.googlesource.com/c/go/+/295309
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
still needs morestack
still needs results
lots of corner cases also not dealt with.
For #40724.
Change-Id: I03abdf1e8363d75c52969560b427e488a48cd37a
Reviewed-on: https://go-review.googlesource.com/c/go/+/293889
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Also handles case where OpArg does not escape but has its address
taken.
May have exposed a lurking bug in 1.16 expandCalls,
if e.g., loading len(someArrayOfstructThing[0].secondStringField)
from a local. Maybe.
For #40724.
Change-Id: I0298c4ad5d652b5e3d7ed6a62095d59e2d8819c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/293396
Trust: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
in progress; doesn't fully work until they are also passed on
register on the caller side.
For #40724.
Change-Id: I29a6680e60bdbe9d132782530214f2a2b51fb8f6
Reviewed-on: https://go-review.googlesource.com/c/go/+/293394
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
StaticLECall (multiple value in +mem, multiple value result +mem) ->
StaticCall (multiple ergister value in +mem,
multiple register-sized-value result +mem) ->
ARCH CallStatic (multiple ergister value in +mem,
multiple register-sized-value result +mem)
But the architecture-dependent stuff is indifferent to whether
it is mem->mem or (mem)->(mem) until Prog generation.
Deal with OpSelectN -> Prog in ssagen/ssa.go, others, as they
appear.
For #40724.
Change-Id: I1d0436f6371054f1881862641d8e7e418e4a6a16
Reviewed-on: https://go-review.googlesource.com/c/go/+/293391
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
Now that the only remaining ir.Node implementation that is stored
(directly) into ssa.Aux, we can rewrite all of the conversions between
ir.Node and ssa.Aux to use *ir.Name instead.
rf doesn't have a way to rewrite the type switch case clauses, so we
just use sed instead. There's only a handful, and they're the only
times that "case ir.Node" appears anyway.
The next CL will move the tag method declarations so that ir.Node no
longer implements ssa.Aux.
Passes buildall w/ toolstash -cmp.
Updates #42982.
[git-generate]
cd src/cmd/compile/internal
sed -i -e 's/case ir.Node/case *ir.Name/' gc/plive.go */ssa.go
cd ssa
rf '
ex . ../gc {
import "cmd/compile/internal/ir"
var v *Value
v.Aux.(ir.Node) -> v.Aux.(*ir.Name)
var n ir.Node
var asAux func(Aux)
strict n # only match ir.Node-typed expressions; not *ir.Name
implicit asAux # match implicit assignments to ssa.Aux
asAux(n) -> n.(*ir.Name)
}
'
Change-Id: I3206ef5f12a7cfa37c5fecc67a1ca02ea4d52b32
Reviewed-on: https://go-review.googlesource.com/c/go/+/275789
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
The plan is to introduce a Node interface that replaces the old *Node pointer-to-struct.
The previous CL defined an interface INode modeling a *Node.
This CL:
- Changes all references outside internal/ir to use INode,
along with many references inside internal/ir as well.
- Renames Node to node.
- Renames INode to Node
So now ir.Node is an interface implemented by *ir.node, which is otherwise inaccessible,
and the code outside package ir is now (clearly) using only the interface.
The usual rule is never to redefine an existing name with a new meaning,
so that old code that hasn't been updated gets a "unknown name" error
instead of more mysterious errors or silent misbehavior. That rule would
caution against replacing Node-the-struct with Node-the-interface,
as in this CL, because code that says *Node would now be using a pointer
to an interface. But this CL is being landed at the same time as another that
moves Node from gc to ir. So the net effect is to replace *gc.Node with ir.Node,
which does follow the rule: any lingering references to gc.Node will be told
it's gone, not silently start using pointers to interfaces. So the rule is followed
by the CL sequence, just not this specific CL.
Overall, the loss of inlining caused by using interfaces cuts the compiler speed
by about 6%, a not insignificant amount. However, as we convert the representation
to concrete structs that are not the giant Node over the next weeks, that speed
should come back as more of the compiler starts operating directly on concrete types
and the memory taken up by the graph of Nodes drops due to the more precise
structs. Honestly, I was expecting worse.
% benchstat bench.old bench.new
name old time/op new time/op delta
Template 168ms ± 4% 182ms ± 2% +8.34% (p=0.000 n=9+9)
Unicode 72.2ms ±10% 82.5ms ± 6% +14.38% (p=0.000 n=9+9)
GoTypes 563ms ± 8% 598ms ± 2% +6.14% (p=0.006 n=9+9)
Compiler 2.89s ± 4% 3.04s ± 2% +5.37% (p=0.000 n=10+9)
SSA 6.45s ± 4% 7.25s ± 5% +12.41% (p=0.000 n=9+10)
Flate 105ms ± 2% 115ms ± 1% +9.66% (p=0.000 n=10+8)
GoParser 144ms ±10% 152ms ± 2% +5.79% (p=0.011 n=9+8)
Reflect 345ms ± 9% 370ms ± 4% +7.28% (p=0.001 n=10+9)
Tar 149ms ± 9% 161ms ± 5% +8.05% (p=0.001 n=10+9)
XML 190ms ± 3% 209ms ± 2% +9.54% (p=0.000 n=9+8)
LinkCompiler 327ms ± 2% 325ms ± 2% ~ (p=0.382 n=8+8)
ExternalLinkCompiler 1.77s ± 4% 1.73s ± 6% ~ (p=0.113 n=9+10)
LinkWithoutDebugCompiler 214ms ± 4% 211ms ± 2% ~ (p=0.360 n=10+8)
StdCmd 14.8s ± 3% 15.9s ± 1% +6.98% (p=0.000 n=10+9)
[Geo mean] 480ms 510ms +6.31%
name old user-time/op new user-time/op delta
Template 223ms ± 3% 237ms ± 3% +6.16% (p=0.000 n=9+10)
Unicode 103ms ± 6% 113ms ± 3% +9.53% (p=0.000 n=9+9)
GoTypes 758ms ± 8% 800ms ± 2% +5.55% (p=0.003 n=10+9)
Compiler 3.95s ± 2% 4.12s ± 2% +4.34% (p=0.000 n=10+9)
SSA 9.43s ± 1% 9.74s ± 4% +3.25% (p=0.000 n=8+10)
Flate 132ms ± 2% 141ms ± 2% +6.89% (p=0.000 n=9+9)
GoParser 177ms ± 9% 183ms ± 4% ~ (p=0.050 n=9+9)
Reflect 467ms ±10% 495ms ± 7% +6.17% (p=0.029 n=10+10)
Tar 183ms ± 9% 197ms ± 5% +7.92% (p=0.001 n=10+10)
XML 249ms ± 5% 268ms ± 4% +7.82% (p=0.000 n=10+9)
LinkCompiler 544ms ± 5% 544ms ± 6% ~ (p=0.863 n=9+9)
ExternalLinkCompiler 1.79s ± 4% 1.75s ± 6% ~ (p=0.075 n=10+10)
LinkWithoutDebugCompiler 248ms ± 6% 246ms ± 2% ~ (p=0.965 n=10+8)
[Geo mean] 483ms 504ms +4.41%
[git-generate]
cd src/cmd/compile/internal/ir
: # We need to do the conversion in multiple steps, so we introduce
: # a temporary type alias that will start out meaning the pointer-to-struct
: # and then change to mean the interface.
rf '
mv Node OldNode
add node.go \
type Node = *OldNode
'
: # It should work to do this ex in ir, but it misses test files, due to a bug in rf.
: # Run the command in gc to handle gc's tests, and then again in ssa for ssa's tests.
cd ../gc
rf '
ex . ../arm ../riscv64 ../arm64 ../mips64 ../ppc64 ../mips ../wasm {
import "cmd/compile/internal/ir"
*ir.OldNode -> ir.Node
}
'
cd ../ssa
rf '
ex {
import "cmd/compile/internal/ir"
*ir.OldNode -> ir.Node
}
'
: # Back in ir, finish conversion clumsily with sed,
: # because type checking and circular aliases do not mix.
cd ../ir
sed -i '' '
/type Node = \*OldNode/d
s/\*OldNode/Node/g
s/^func (n Node)/func (n *OldNode)/
s/OldNode/node/g
s/type INode interface/type Node interface/
s/var _ INode = (Node)(nil)/var _ Node = (*node)(nil)/
' *.go
gofmt -w *.go
sed -i '' '
s/{Func{}, 136, 248}/{Func{}, 152, 280}/
s/{Name{}, 32, 56}/{Name{}, 44, 80}/
s/{Param{}, 24, 48}/{Param{}, 44, 88}/
s/{node{}, 76, 128}/{node{}, 88, 152}/
' sizeof_test.go
cd ../ssa
sed -i '' '
s/{LocalSlot{}, 28, 40}/{LocalSlot{}, 32, 48}/
' sizeof_test.go
cd ../gc
sed -i '' 's/\*ir.Node/ir.Node/' mkbuiltin.go
cd ../../../..
go install std cmd
cd cmd/compile
go test -u || go test -u
Change-Id: I196bbe3b648e4701662e4a2bada40bf155e2a553
Reviewed-on: https://go-review.googlesource.com/c/go/+/272935
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The cycle hacks existed because gc needed to import ssa
which need to know about gc.Node. But now that's ir.Node,
and there's no cycle anymore.
Don't know how much it matters but LocalSlot is now
one word shorter than before, because it holds a pointer
instead of an interface for the *Node. That won't last long.
Now that they're not necessary for interface satisfaction,
IsSynthetic and IsAutoTmp can move to top-level ir functions.
Change-Id: Ie511e93466cfa2b17d9a91afc4bd8d53fdb80453
Reviewed-on: https://go-review.googlesource.com/c/go/+/272931
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
My last 387 CL. So sad ... ... ... ... not!
Fixes#40255
Change-Id: I8d4ddb744b234b8adc735db2f7c3c7b6d8bbdfa4
Reviewed-on: https://go-review.googlesource.com/c/go/+/258957
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
I think they are no longer experimental status. Might as well promote
them to permanent.
Change-Id: Id1259601b3dd2061dd60df86ee48080bfb575d2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/249857
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
When setting the edge state in register allocation we should only
be setting each register once. It is not possible for a register
to hold multiple values at once.
This CL converts the runtime error seen in #38195 into an internal
compiler error (ICE). It is better for the compiler to fail than
generate an incorrect program.
The bug reported in #38195 is now exposed as:
./parserc.go:459:11: internal compiler error: 'yaml_parser_parse_node': R5 is already set (v1074/v1241)
[stack trace]
Updates #38195.
Change-Id: Id95842fd850b95494cbd472b6fd5a55513ecacec
Reviewed-on: https://go-review.googlesource.com/c/go/+/228060
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
When deallocating the input register to a phi so that the phi
itself could be allocated to that register the code was also
deallocating all copies of that phi input value. Those copies
of the value could still be live and if they were the register
allocator could reuse them incorrectly to hold speculative
copies of other phi inputs. This causes strange bugs.
No test because this is a very obscure scenario that is hard
to replicate but CL 228060 adds an assertion to the compiler
that does trigger when running the std tests on linux/s390x
without this CL applied. Hopefully that assertion will prevent
future regressions.
Fixes#38195.
Change-Id: Id975dadedd731c7bb21933b9ea6b17daaa5c9e1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/228061
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Once defined, a stack slot holding an open-coded defer arg should always be marked
live, since it may be used at any time if there is a panic. These stack slots are
typically kept live naturally by the open-defer code inlined at each return/exit point.
However, we need to do extra work to make sure that they are kept live if a
function has an infinite loop or a panic exit.
For this fix, only in the case of a function that is using open-coded defers, we
compute the set of blocks (most often empty) that cannot reach a return or a
BlockExit (panic) because of an infinite loop. Then, for each block b which
cannot reach a return or BlockExit or is a BlockExit block, we mark each defer arg
slot as live, as long as the definition of the defer arg slot dominates block b.
For this change, had to export (*Func).sdom (-> Sdom) and SparseTree.isAncestorEq
(-> IsAncestorEq)
Updates #35277
Change-Id: I7b53c9bd38ba384a3794386dd0eb94e4cbde4eb1
Reviewed-on: https://go-review.googlesource.com/c/go/+/204802
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This is part two if the nacl removal. Part 1 was CL 199499.
This CL removes amd64p32 support, which might be useful in the future
if we implement the x32 ABI. It also removes the nacl bits in the
toolchain, and some remaining nacl bits.
Updates #30439
Change-Id: I2475d5bb066d1b474e00e40d95b520e7c2e286e1
Reviewed-on: https://go-review.googlesource.com/c/go/+/200077
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For commuting ops, check whether the second argument is dead before
checking if the first argument is rematerializeable. Reusing the register
holding a dead value is always best.
Fixes#33580
Change-Id: I7372cfc03d514e6774d2d9cc727a3e6bf6ce2657
Reviewed-on: https://go-review.googlesource.com/c/go/+/199559
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Before this change, wasm only used float variables with a size of 64 bit
and applied rounding to 32 bit precision where necessary. This change
adds proper 32 bit float variables.
Reduces the size of pkg/js_wasm by 254 bytes.
Change-Id: Ieabe846a8cb283d66def3cdf11e2523b3b31f345
Reviewed-on: https://go-review.googlesource.com/c/go/+/195117
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Use the following (suboptimal) script to obtain a list of possible
typos:
#!/usr/bin/env sh
set -x
git ls-files |\
grep -e '\.\(c\|cc\|go\)$' |\
xargs -n 1\
awk\
'/\/\// { gsub(/.*\/\//, ""); print; } /\/\*/, /\*\// { gsub(/.*\/\*/, ""); gsub(/\*\/.*/, ""); }' |\
hunspell -d en_US -l |\
grep '^[[:upper:]]\{0,1\}[[:lower:]]\{1,\}$' |\
grep -v -e '^.\{1,4\}$' -e '^.\{16,\}$' |\
sort -f |\
uniq -c |\
awk '$1 == 1 { print $2; }'
Then, go through the results manually and fix the most obvious typos in
the non-vendored code.
Change-Id: I3cb5830a176850e1a0584b8a40b47bde7b260eae
Reviewed-on: https://go-review.googlesource.com/c/go/+/193848
Reviewed-by: Robert Griesemer <gri@golang.org>
We shouldn't mask to desired registers if we haven't masked out all the
forbidden registers yet. In this path we haven't masked out the nospill
registers yet. If the resulting mask contains only nospill registers, then
allocReg fails.
This can only happen on resultNotInArgs-marked instructions, which exist
only on the ARM64, MIPS, MIPS64, and PPC64 ports.
Maybe there's a better way to handle resultNotInArgs instructions.
But for 1.13, this is a low-risk fix.
Fixes#33355
Change-Id: I1082f78f798d1371bde65c58cc265540480e4fa4
Reviewed-on: https://go-review.googlesource.com/c/go/+/188178
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Currently, runtime.KeepAlive applied on a stack object doesn't
actually keeps the stack object alive, and the heap object
referenced from it could be collected. This is because the
address of the stack object is rematerializeable, and we just
ignored KeepAlive on rematerializeable values. This CL fixes it.
Fixes#30476.
Change-Id: Ic1f75ee54ed94ea79bd46a8ddcd9e81d01556d1d
Reviewed-on: https://go-review.googlesource.com/c/164537
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>