Instead we can use t.nod.Pos.
Change-Id: I643ee3226e402e38d4c77e8f328cbe83e55eac5c
Reviewed-on: https://go-review.googlesource.com/38309
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
CL 27254 changed a constant string to a byte array
in encoding/hex and got significant performance
improvements.
hex.Encode used the string twice in a single function.
The rewrite rules lower constant strings into components.
The pointer component requires an aux symbol.
The existing implementation created a new aux symbol every time.
As a result, constant string pointers were never CSE'd.
Tighten then moved the pointer calculation next to the uses, i.e.
into the loop.
The re-use of aux syms enabled by this CL
occurs 3691 times during make.bash.
This CL should not go in without CL 38338
or something like it.
Change-Id: Ibbf5b17283c0e31821d04c7e08d995c654de5663
Reviewed-on: https://go-review.googlesource.com/28219
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This makes the overall naming and use of the functions
to create a Type more consistent.
Passes toolstash -cmp.
Change-Id: Ie0d40b42cc32b5ecf5f20502675a225038ea40e4
Reviewed-on: https://go-review.googlesource.com/38354
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Mapping all empty interfaces onto the same Type
allows better reuse of the ptrTo and sliceOf
Type caches for *interface{} and []interface{}.
This has little compiler performance impact now,
but it will be helpful in the future,
when we will eagerly populate some of those caches.
Passes toolstash-check.
Change-Id: I17daee599a129b0b2f5f3025c1be43d569d6782c
Reviewed-on: https://go-review.googlesource.com/38344
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This reduces the number of calls back into the
gc Type routines, which will help performance
in a concurrent backend.
It also reduces the number of callsites
that must be considered in making the transition.
Passes toolstash-check -all. No compiler performance changes.
Updates #15756
Change-Id: Ic7a8f1daac7e01a21658ae61ac118b2a70804117
Reviewed-on: https://go-review.googlesource.com/38340
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Prior to this CL, the ssa.Frontend field was responsible
for providing types to the backend during compilation.
However, the types needed by the backend are few and static.
It makes more sense to use a struct for them
and to hang that struct off the ssa.Config,
which is the correct home for readonly data.
Now that Types is a struct, we can clean up the names a bit as well.
This has the added benefit of allowing early construction
of all types needed by the backend.
This will be useful for concurrent backend compilation.
Passes toolstash-check -all. No compiler performance change.
Updates #15756
Change-Id: I021658c8cf2836d6a22bbc20cc828ac38c7da08a
Reviewed-on: https://go-review.googlesource.com/38336
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
While we're here, also eliminate a few more Curfn uses.
Passes toolstash -cmp. No compiler performance impact.
Updates #15756
Change-Id: Ib8db9e23467bbaf16cc44bf62d604910f733d6b8
Reviewed-on: https://go-review.googlesource.com/38331
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This is a first step towards eliminating the
Curfn global in the backend.
There's more to do.
Passes toolstash -cmp. No compiler performance impact.
Updates #15756
Change-Id: Ib09f550a001e279a5aeeed0f85698290f890939c
Reviewed-on: https://go-review.googlesource.com/38232
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Suggested by mdempsky in CL 38232.
This allows us to use the Frontend field
to associate frontend state and information
with a function.
See the following CL in the series for examples.
This is a giant CL, but it is almost entirely routine refactoring.
The ssa test API is starting to feel a bit unwieldy.
I will clean it up separately, once the dust has settled.
Passes toolstash -cmp.
Updates #15756
Change-Id: I71c573bd96ff7251935fce1391b06b1f133c3caf
Reviewed-on: https://go-review.googlesource.com/38327
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This CL changes the GOARCH.Init functions to take gc.Thearch as a
parameter, which gc.Main supplies.
Additionally, the x86 backend is refactored to decide within Init
whether to use the 387 or SSE2 instruction generators, rather than for
each individual SSA Value/Block.
Passes toolstash-check -all.
Change-Id: Ie6305a6cd6f6ab4e89ecbb3cbbaf5ffd57057a24
Reviewed-on: https://go-review.googlesource.com/38301
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
I don't know that it exists for any other architectures.
Update #18616
Change-Id: Idfe5dee251764d32787915889ec0be4bebc5be24
Reviewed-on: https://go-review.googlesource.com/38323
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This makes ssa.Func, ssa.Cache, and ssa.Config fulfill
the roles laid out for them in CL 38160.
The only non-trivial change in this CL is how cached
values and blocks get IDs. Prior to this CL, their IDs were
assigned as part of resetting the cache, and only modified
IDs were reset. This required knowing how many values and
blocks were modified, which required a tight coupling between
ssa.Func and ssa.Config. To eliminate that coupling,
we now zero values and blocks during reset,
and assign their IDs when they are used.
Since unused values and blocks have ID == 0,
we can efficiently find the last used value/block,
to avoid zeroing everything.
Bulk zeroing is efficient, but not efficient enough
to obviate the need to avoid zeroing everything every time.
As a happy side-effect, ssa.Func.Free is no longer necessary.
DebugHashMatch and friends now belong in func.go.
They have been left in place for clarity and review.
I will move them in a subsequent CL.
Passes toolstash -cmp. No compiler performance impact.
No change in 'go test cmd/compile/internal/ssa' execution time.
Change-Id: I2eb7af58da067ef6a36e815a6f386cfe8634d098
Reviewed-on: https://go-review.googlesource.com/38167
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
See https://go-review.googlesource.com/#/c/38313/ for background.
It turns out that only a few tests checked for this.
The new error message is shorter and very clear.
Change-Id: I8ab4ad59fb023c8b54806339adc23aefd7dc7b07
Reviewed-on: https://go-review.googlesource.com/38314
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This is an evolution of https://go-review.googlesource.com/33616, as discussed
via email with Robert (gri):
$ cat foobar.go
package main
func main() {
a := "foo", "bar"
}
before:
./foobar.go:4:4: assignment count mismatch: want 1 values, got 2
after:
./foobar.go:4:4: assignment count mismatch: cannot assign 2 values to 1 variables
We could likely also eliminate the "assignment count mismatch" prefix now
without losing any information, but that string is matched by a number of
tests.
Change-Id: Ie6fc8a7bbd0ebe841d53e66e5c2f49868decf761
Reviewed-on: https://go-review.googlesource.com/38313
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
name old time/op new time/op delta
LeadingZeros-4 2.00ns ± 0% 1.34ns ± 1% -33.02% (p=0.000 n=8+10)
LeadingZeros16-4 1.62ns ± 0% 1.57ns ± 0% -3.09% (p=0.001 n=8+9)
LeadingZeros32-4 2.14ns ± 0% 1.48ns ± 0% -30.84% (p=0.002 n=8+10)
LeadingZeros64-4 2.06ns ± 1% 1.33ns ± 0% -35.08% (p=0.000 n=8+8)
8-bit args is a special case - the Go code is really fast because
it is just a single table lookup. So I've disabled that for now.
Intrinsics were actually slower:
LeadingZeros8-4 1.22ns ± 3% 1.58ns ± 1% +29.56% (p=0.000 n=10+10)
Update #18616
Change-Id: Ia9c289b9ba59c583ea64060470315fd637e814cf
Reviewed-on: https://go-review.googlesource.com/38311
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Remove size AuxInt in Store, and alignment in Move/Zero. We still
pass size AuxInt to Move/Zero, as it is used for partial Move/Zero
lowering (e.g. cmd/compile/internal/ssa/gen/386.rules:288).
SizeAndAlign is gone.
Passes "toolstash -cmp" on std.
Change-Id: I1ca34652b65dd30de886940e789fcf41d521475d
Reviewed-on: https://go-review.googlesource.com/38150
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Now that the write barrier insertion is moved to SSA, the SSA
building code can be simplified.
Updates #17583.
Change-Id: I5cacc034b11aa90b0abe6f8dd97e4e3994e2bc25
Reviewed-on: https://go-review.googlesource.com/36840
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
When the compiler insert write barriers, the frontend makes
conservative decisions at an early stage. This sometimes have
false positives because of the lack of information, for example,
writes on stack. SSA's writebarrier pass identifies writes on
stack and eliminates write barriers for them.
This CL moves write barrier insertion into SSA. The frontend no
longer makes decisions about write barriers, and simply does
normal assignments and emits normal Store ops when building SSA.
SSA writebarrier pass inserts write barrier for Stores when needed.
There, it has better information about the store because Phi and
Copy propagation are done at that time.
This CL only changes StoreWB to Store in gc/ssa.go. A followup CL
simplifies SSA building code.
Updates #17583.
Change-Id: I4592d9bc0067503befc169c50b4e6f4765673bec
Reviewed-on: https://go-review.googlesource.com/36839
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
For SSA Store/Move/Zero ops, attach the type of the value being
stored to the op as the Aux field. This type will be used for
write barrier insertion (in a followup CL). Since SSA passes
do not accurately propagate types of values (because of type
casting), we can't simply use type of the store's arguments
for write barrier insertion.
Passes "toolstash -cmp" on std.
Updates #17583.
Change-Id: I051d5e5c482931640d1d7d879b2a6bb91f2e0056
Reviewed-on: https://go-review.googlesource.com/36838
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Implement math/bits.TrailingZerosX using intrinsics.
Generally reorganize the intrinsic spec a bit.
The instrinsics data structure is now built at init time.
This will make doing the other functions in math/bits easier.
Update sys.CtzX to return int instead of uint{64,32} so it
matches math/bits.TrailingZerosX.
Improve the intrinsics a bit for amd64. We don't need the CMOV
for <64 bit versions.
Update #18616
Change-Id: Ic1c5339c943f961d830ae56f12674d7b29d4ff39
Reviewed-on: https://go-review.googlesource.com/38155
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Interface wrapper functions now get compiled eagerly in some cases.
Consequently, they may be present in multiple translation units.
Mark them as DUPOK, just like closures.
Fixes#19548Fixes#19550
Change-Id: Ibe74adb5a62dbf6447db37fde22dcbb3479969ef
Reviewed-on: https://go-review.googlesource.com/38156
Reviewed-by: David Chase <drchase@google.com>
In the SSA CFG, TEXT, RET, and JMP instructions correspond to Blocks,
not Values. Rework liveness analysis so that progeffects only cares
about Progs that result from Values, and handle Blocks separately.
Passes toolstash-check -all.
Change-Id: Ic23719c75b0421fdb51382a08dac18c3ba042b32
Reviewed-on: https://go-review.googlesource.com/38085
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
The fmtmode and fmtpkgpfx globals stand in the
way of making the compiler more concurrent (#15756).
This CL removes them.
The natural way to eliminate a global is to explicitly
thread it as a parameter through all function calls.
However, most of the functions in gc/fmt.go
get called indirectly, by way of fmt format strings,
so there's nowhere natural to add a parameter.
Since there are only a few fmtmode modes,
use named types to distinguish between modes.
For example, fmtNodeErr, fmtNodeDbg, and fmtNodeTypeId
are all gc.Node, but they print in different modes.
Varying the type allows us to thread mode through fmt.
Handle fmtpkgpfx by converting it to a printing mode,
FTypeIdName, and using the same type-based approach.
To avoid a loss of readability and danger of bugs
from introducing conversions at all call sites,
instead add a helper that systematically modifies the args.
The only remaining gc/fmt.go global is dumpdepth.
Since that is used for debugging only,
it that can be handled with a global mutex,
or some similarly basic, if inefficient, protection.
Passes toolstash -cmp. No compiler performance impact.
For future reference, other options for threading state
that were considered and rejected:
* Wrapping values in structs, such as:
type fmtNode struct {
n *Node
mode fmtMode
}
This reduces the proliferation of types, and supports
easily adding extra local parameters.
However, putting such a struct into an interface{} allocates.
This is unacceptable in this particular area of code.
* Passing state via precision, such as:
fmt.Fprintf("%*v", mode, n)
where mode is the state encoded as an integer.
This avoids extra allocations, but it is out of keeping
with the intended semantics of precision, and is less readable.
* Modify the fmt package to support setting/getting context
via fmt.State. Unavailable due to Go 1 compatibility,
and probably the wrong solution anyway.
* Give up on package fmt. This would be a huge readability
regression and cause high code churn.
* Attempt a de-novo rewrite that circumvents these problems.
Too high a risk of bugs, with insufficient reward for the effort,
particularly since long term plans call for elimination
of gc.Node.
Change-Id: Iea2440d5a34a938e64273707de27e3a897cb41d1
Reviewed-on: https://go-review.googlesource.com/38147
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
With this change, code like
h := sha1.New()
h.Write(buf)
sum := h.Sum()
gets compiled into static calls rather than
interface calls, because the compiler is able
to prove that 'h' is really a *sha1.digest.
The InterCall re-write rule hits a few dozen times
during make.bash, and hundreds of times during all.bash.
The most common pattern identified by the compiler
is a constructor like
func New() Interface { return &impl{...} }
where the constructor gets inlined into the caller,
and the result is used immediately. Examples include
{sha1,md5,crc32,crc64,...}.New, base64.NewEncoder,
base64.NewDecoder, errors.New, net.Pipe, and so on.
Some existing benchmarks that change on darwin/amd64:
Crc64/ISO4KB-8 2.67µs ± 1% 2.66µs ± 0% -0.36% (p=0.015 n=10+10)
Crc64/ISO1KB-8 694ns ± 0% 690ns ± 1% -0.59% (p=0.001 n=10+10)
Adler32KB-8 473ns ± 1% 471ns ± 0% -0.39% (p=0.010 n=10+9)
On architectures like amd64, the reduction in code size
appears to contribute more to benchmark improvements than just
removing the indirect call, since that branch gets predicted
accurately when called in a loop.
Updates #19361
Change-Id: I57d4dc21ef40a05ec0fbd55a9bb0eb74cdc67a3d
Reviewed-on: https://go-review.googlesource.com/38139
Run-TryBot: Philip Hofer <phofer@umich.edu>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Bad pragmas should never make it to the backend.
I've confirmed manually that the error position is unchanged.
Updates #15756
Updates #19250
Change-Id: If14f7ce868334f809e337edc270a49680b26f48e
Reviewed-on: https://go-review.googlesource.com/38152
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
There were a surprising number of places
in the tree that used yyerror for failed internal
consistency checks. Switch them to Fatalf.
Updates #15756
Updates #19250
Change-Id: Ie4278148185795a28ff3c27dacffc211cda5bbdd
Reviewed-on: https://go-review.googlesource.com/38153
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This reverts commit 4e0c7c3f61.
Reason for revert: The presence-of-optimization test program is fragile, breaks under noopt, and might break if the Go libraries are tweaked. It needs to be (re)written without reference to other packages.
Change-Id: I3aaf1ab006a1a255f961a978e9c984341740e3c7
Reviewed-on: https://go-review.googlesource.com/38097
Reviewed-by: Keith Randall <khr@golang.org>
This abstracts creation of ACALL Progs into package gc. The main
benefit of this today is we can refactor away a lot of common
boilerplate code.
Later, once liveness analysis happens on the SSA graph, this will also
provide an easy insertion point for emitting the PCDATA Progs
immediately before call instructions.
Passes toolstash-check -all.
Change-Id: Ia15108ace97201cd84314f1ca916dfeb4f09d61c
Reviewed-on: https://go-review.googlesource.com/38081
Reviewed-by: Keith Randall <khr@golang.org>
