Commit graph

154 commits

Author SHA1 Message Date
Matthew Dempsky
d96b7fbf98 cmd/compile: rewrite f(g()) for multi-value g() during typecheck
This CL moves order.go's copyRet logic for rewriting f(g()) into t1,
t2, ... = g(); f(t1, t2, ...) earlier into typecheck. This allows the
rest of the compiler to stop worrying about multi-value functions
appearing outside of OAS2FUNC nodes.

This changes compiler behavior in a few observable ways:

1. Typechecking error messages for builtin functions now use general
case error messages rather than unnecessarily differing ones.

2. Because f(g()) is rewritten before inlining, saved inline bodies
now see the rewritten form too. This could be addressed, but doesn't
seem worthwhile.

3. Most notably, this simplifies escape analysis and fixes a memory
corruption issue in esc.go. See #29197 for details.

Fixes #15992.
Fixes #29197.

Change-Id: I86a70668301efeec8fbd11fe2d242e359a3ad0af
Reviewed-on: https://go-review.googlesource.com/c/153841
Reviewed-by: Robert Griesemer <gri@golang.org>
2019-02-28 22:50:08 +00:00
Cherry Zhang
0349f29a55 cmd/compile: flow interface data to heap if CONVIFACE of a non-direct interface escapes
Consider the following code:

func f(x []*T) interface{} {
	return x
}

It returns an interface that holds a heap copy of x (by calling
convT2I or friend), therefore x escape to heap. The current
escape analysis only recognizes that x flows to the result. This
is not sufficient, since if the result does not escape, x's
content may be stack allocated and this will result a
heap-to-stack pointer, which is bad.

Fix this by realizing that if a CONVIFACE escapes and we're
converting from a non-direct interface type, the data needs to
escape to heap.

Running "toolstash -cmp" on std & cmd, the generated machine code
are identical for all packages. However, the export data (escape
tags) differ in the following packages. It looks to me that all
are similar to the "f" above, where the parameter should escape
to heap.

io/ioutil/ioutil.go:118
	old: leaking param: r to result ~r1 level=0
	new: leaking param: r

image/image.go:943
	old: leaking param: p to result ~r0 level=1
	new: leaking param content: p

net/url/url.go:200
	old: leaking param: s to result ~r2 level=0
	new: leaking param: s

(as a consequence)
net/url/url.go:183
	old: leaking param: s to result ~r1 level=0
	new: leaking param: s

net/url/url.go:194
	old: leaking param: s to result ~r1 level=0
	new: leaking param: s

net/url/url.go:699
	old: leaking param: u to result ~r0 level=1
	new: leaking param: u

net/url/url.go:775
	old: (*URL).String u does not escape
	new: leaking param content: u

net/url/url.go:1038
	old: leaking param: u to result ~r0 level=1
	new: leaking param: u

net/url/url.go:1099
	old: (*URL).MarshalBinary u does not escape
	new: leaking param content: u

flag/flag.go:235
	old: leaking param: s to result ~r0 level=1
	new: leaking param content: s

go/scanner/errors.go:105
	old: leaking param: p to result ~r0 level=0
	new: leaking param: p

database/sql/sql.go:204
	old: leaking param: ns to result ~r0 level=0
	new: leaking param: ns

go/constant/value.go:303
	old: leaking param: re to result ~r2 level=0, leaking param: im to result ~r2 level=0
	new: leaking param: re, leaking param: im

go/constant/value.go:846
	old: leaking param: x to result ~r1 level=0
	new: leaking param: x

encoding/xml/xml.go:518
	old: leaking param: d to result ~r1 level=2
	new: leaking param content: d

encoding/xml/xml.go:122
	old: leaking param: leaking param: t to result ~r1 level=0
	new: leaking param: t

crypto/x509/verify.go:506
	old: leaking param: c to result ~r8 level=0
	new: leaking param: c

crypto/x509/verify.go:563
	old: leaking param: c to result ~r3 level=0, leaking param content: c
	new: leaking param: c

crypto/x509/verify.go:615
	old: (nothing)
	new: leaking closure reference c

crypto/x509/verify.go:996
	old: leaking param: c to result ~r1 level=0, leaking param content: c
	new: leaking param: c

net/http/filetransport.go:30
	old: leaking param: fs to result ~r1 level=0
	new: leaking param: fs

net/http/h2_bundle.go:2684
	old: leaking param: mh to result ~r0 level=2
	new: leaking param content: mh

net/http/h2_bundle.go:7352
	old: http2checkConnHeaders req does not escape
	new: leaking param content: req

net/http/pprof/pprof.go:221
	old: leaking param: name to result ~r1 level=0
	new: leaking param: name

cmd/internal/bio/must.go:21
	old: leaking param: w to result ~r1 level=0
	new: leaking param: w

Fixes #29353.

Change-Id: I7e7798ae773728028b0dcae5bccb3ada51189c68
Reviewed-on: https://go-review.googlesource.com/c/162829
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: David Chase <drchase@google.com>
2019-02-21 15:14:45 +00:00
Cherry Zhang
be09bdf589 cmd/compile: fix unnamed parameter handling in escape analysis
For recursive functions, the parameters were iterated using
fn.Name.Defn.Func.Dcl, which does not include unnamed/blank
parameters. This results in a mismatch in formal-actual
assignments, for example,

func f(_ T, x T)

f(a, b) should result in { _=a, x=b }, but the escape analysis
currently sees only { x=a } and drops b on the floor. This may
cause b to not escape when it should (or a escape when it should
not).

Fix this by using fntype.Params().FieldSlice() instead, which
does include unnamed parameters.

Also add a sanity check that ensures all the actual parameters
are consumed.

Fixes #29000

Change-Id: Icd86f2b5d71e7ebbab76e375b7702f62efcf59ae
Reviewed-on: https://go-review.googlesource.com/c/152617
Reviewed-by: Keith Randall <khr@golang.org>
2018-12-04 23:01:00 +00:00
Josh Bleecher Snyder
bc43889566 cmd/compile: bulk rename
This change does a bulk rename of several identifiers in the compiler.
See #27167 and https://docs.google.com/document/d/19_ExiylD9MRfeAjKIfEsMU1_RGhuxB9sA0b5Zv7byVI/
for context and for discussion of these particular renames.

Commands run to generate this change:

gorename -from '"cmd/compile/internal/gc".OPROC' -to OGO
gorename -from '"cmd/compile/internal/gc".OCOM' -to OBITNOT
gorename -from '"cmd/compile/internal/gc".OMINUS' -to ONEG
gorename -from '"cmd/compile/internal/gc".OIND' -to ODEREF
gorename -from '"cmd/compile/internal/gc".OARRAYBYTESTR' -to OBYTES2STR
gorename -from '"cmd/compile/internal/gc".OARRAYBYTESTRTMP' -to OBYTES2STRTMP
gorename -from '"cmd/compile/internal/gc".OARRAYRUNESTR' -to ORUNES2STR
gorename -from '"cmd/compile/internal/gc".OSTRARRAYBYTE' -to OSTR2BYTES
gorename -from '"cmd/compile/internal/gc".OSTRARRAYBYTETMP' -to OSTR2BYTESTMP
gorename -from '"cmd/compile/internal/gc".OSTRARRAYRUNE' -to OSTR2RUNES

gorename -from '"cmd/compile/internal/gc".Etop' -to ctxStmt
gorename -from '"cmd/compile/internal/gc".Erv' -to ctxExpr
gorename -from '"cmd/compile/internal/gc".Ecall' -to ctxCallee
gorename -from '"cmd/compile/internal/gc".Efnstruct' -to ctxMultiOK
gorename -from '"cmd/compile/internal/gc".Easgn' -to ctxAssign
gorename -from '"cmd/compile/internal/gc".Ecomplit' -to ctxCompLit

Not altered: parameters and local variables (mostly in typecheck.go) named top,
which should probably now be called ctx (and which should probably have a named type).
Also not altered: Field called Top in gc.Func.

gorename -from '"cmd/compile/internal/gc".Node.Isddd' -to IsDDD
gorename -from '"cmd/compile/internal/gc".Node.SetIsddd' -to SetIsDDD
gorename -from '"cmd/compile/internal/gc".nodeIsddd' -to nodeIsDDD
gorename -from '"cmd/compile/internal/types".Field.Isddd' -to IsDDD
gorename -from '"cmd/compile/internal/types".Field.SetIsddd' -to SetIsDDD
gorename -from '"cmd/compile/internal/types".fieldIsddd' -to fieldIsDDD

Not altered: function gc.hasddd, params and local variables called isddd
Also not altered: fmt.go prints nodes using "isddd(%v)".

cd cmd/compile/internal/gc; go generate

I then manually found impacted comments using exact string match
and fixed them up by hand. The comment changes were trivial.

Passes toolstash-check.

Fixes #27167. If this experiment is deemed a success,
we will open a new tracking issue for renames to do
at the end of the 1.13 cycles.

Change-Id: I2dc541533d2ab0d06cb3d31d65df205ecfb151e8
Reviewed-on: https://go-review.googlesource.com/c/150140
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-11-19 00:02:53 +00:00
Matthew Dempsky
2dda040f19 cmd/compile/internal/gc: represent labels as bare Syms
Avoids allocating an ONAME for OLABEL, OGOTO, and named OBREAK and
OCONTINUE nodes.

Passes toolstash-check.

Change-Id: I359142cd48e8987b5bf29ac100752f8c497261c1
Reviewed-on: https://go-review.googlesource.com/c/145200
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-10-27 07:32:06 +00:00
Matthew Dempsky
2d58fbac2f cmd/compile: extract gc.eqtype as types.Identical
For symmetry with go/types.Identical.

Passes toolstash-check.

Change-Id: Id19c3956e44ed8e2d9f203d15824322cc5842d3d
Reviewed-on: https://go-review.googlesource.com/c/143180
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-10-18 23:44:39 +00:00
Keith Randall
ceb0c371d9 cmd/compile: make []byte("...") more efficient
Do []byte(string) conversions more efficiently when the string
is a constant. Instead of calling stringtobyteslice, allocate
just the space we need and encode the initialization directly.

[]byte("foo") rewrites to the following pseudocode:

var s [3]byte // on heap or stack, depending on whether b escapes
s = *(*[3]byte)(&"foo"[0]) // initialize s from the string
b = s[:]

which generates this assembly:

	0x001d 00029 (tmp1.go:9)	LEAQ	type.[3]uint8(SB), AX
	0x0024 00036 (tmp1.go:9)	MOVQ	AX, (SP)
	0x0028 00040 (tmp1.go:9)	CALL	runtime.newobject(SB)
	0x002d 00045 (tmp1.go:9)	MOVQ	8(SP), AX
	0x0032 00050 (tmp1.go:9)	MOVBLZX	go.string."foo"+2(SB), CX
	0x0039 00057 (tmp1.go:9)	MOVWLZX	go.string."foo"(SB), DX
	0x0040 00064 (tmp1.go:9)	MOVW	DX, (AX)
	0x0043 00067 (tmp1.go:9)	MOVB	CL, 2(AX)
// Then the slice is b = {AX, 3, 3}

The generated code is still not optimal, as it still does load/store
from read-only memory instead of constant stores.  Next CL...

Update #26498
Fixes #10170

Change-Id: I4b990b19f9a308f60c8f4f148934acffefe0a5bd
Reviewed-on: https://go-review.googlesource.com/c/140698
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-10 16:10:40 +00:00
Igor Zhilianin
04dc1b2443 all: fix a bunch of misspellings
Change-Id: I94cebca86706e072fbe3be782d3edbe0e22b9432
GitHub-Last-Rev: 8e15a40545
GitHub-Pull-Request: golang/go#28067
Reviewed-on: https://go-review.googlesource.com/c/140437
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-08 03:12:03 +00:00
Matthew Dempsky
62e5215a2a cmd/compile: merge TPTR32 and TPTR64 as TPTR
Change-Id: I0490098a7235458c5aede1135426a9f19f8584a7
Reviewed-on: https://go-review.googlesource.com/c/76312
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-10-04 04:08:08 +00:00
Iskander Sharipov
499fbb1a8a cmd/compile/internal/gc: unify self-assignment checks in esc.go
Move slice self-assign check into isSelfAssign function.
Make debug output consistent for all self-assignment cases.

Change-Id: I0e4cc7b3c1fcaeace7226dd80a0dc1ea97347a55
Reviewed-on: https://go-review.googlesource.com/136276
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-09-20 09:46:11 +00:00
Iskander Sharipov
713edf8b31 cmd/compile/internal/gc: simplify x = x <op> y to x <op>= y
Change-Id: I5afba2c10372252be4b65dae7a95461722de904f
Reviewed-on: https://go-review.googlesource.com/135835
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-09-19 02:56:21 +00:00
Iskander Sharipov
859cf7fc0f cmd/compile/internal/gc: handle array slice self-assign in esc.go
Instead of skipping all OSLICEARR, skip only ones with non-pointer
array type. For pointers to arrays, it's safe to apply the
self-assignment slicing optimizations.

Refactored the matching code into separate function for readability.

This is an extension to already existing optimization.

On its own, it does not improve any code under std, but
it opens some new optimization opportunities. One
of them is described in the referenced issue.

Updates #7921

Change-Id: I08ac660d3ef80eb15fd7933fb73cf53ded9333ad
Reviewed-on: https://go-review.googlesource.com/133375
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-09-17 11:14:58 +00:00
Iskander Sharipov
2d82465d18 cmd/compile/internal/gc: treat cap/len as safe in mayAffectMemory
OLEN and OCAP can't affect memory state as long as their
arguments don't.

Re-organized case bodies to avoid duplicating same branches for
recursive invocations.

Change-Id: I30407143429f7dd1891badb70df88969ed267535
Reviewed-on: https://go-review.googlesource.com/133555
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-09-17 11:06:01 +00:00
Iskander Sharipov
4cf33e361a cmd/compile/internal/gc: fix mayAffectMemory in esc.go
For OINDEX and other Left+Right nodes, we want the whole
node to be considered as "may affect memory" if either
of Left or Right affect memory. Initial implementation
only considered node as such if both Left and Right were non-safe.

Change-Id: Icfb965a0b4c24d8f83f3722216db068dad2eba95
Reviewed-on: https://go-review.googlesource.com/133275
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-09-05 14:16:25 +00:00
Iskander Sharipov
67ac554d79 cmd/compile/internal/gc: fix invalid positions for sink nodes in esc.go
Make OAS2 and OAS2FUNC sink locations point to the assignment position,
not the nth LHS position.

Fixes #26987

Change-Id: Ibeb9df2da754da8b6638fe1e49e813f37515c13c
Reviewed-on: https://go-review.googlesource.com/129315
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-09-03 16:46:59 +00:00
Iskander Sharipov
ff468a43be cmd/compile/internal/gc: better handling of self-assignments in esc.go
Teach escape analysis to recognize these assignment patterns
as not causing the src to leak:

	val.x = val.y
	val.x[i] = val.y[j]
	val.x1.x2 = val.x1.y2
	... etc

Helps to avoid "leaking param" with assignments showed above.
The implementation is based on somewhat similiar xs=xs[a:b]
special case that is ignored by the escape analysis.

We may figure out more generalized version of this,
but this one looks like a safe step into that direction.

Updates #14858

Change-Id: I6fe5bfedec9c03bdc1d7624883324a523bd11fde
Reviewed-on: https://go-review.googlesource.com/126395
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-09-03 14:28:51 +00:00
Iskander Sharipov
0c706fddce cmd/compile/internal/gc: remove commented-out code from esc.go
Also adjust some comments to where they belong.

Change-Id: Ifbb38052401b0d33d7bb9800f56a20ce8f39c25f
Reviewed-on: https://go-review.googlesource.com/127761
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-08-22 16:55:08 +00:00
David Chase
a12c1f26e4 cmd/compile: improve escape analysis explanation
No code changes, only revised comments in an attempt to make
escape analysis slightly less confusing.

Updates #23109.

Change-Id: I5ee6cea0946ced63f6210ac4484a088bcdd862fb
Reviewed-on: https://go-review.googlesource.com/121001
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-06-26 20:00:51 +00:00
Cherry Zhang
3042463d61 cmd/compile: in escape analysis, use element type for OIND of slice
The escape analysis models the flow of "content" of X with a
level of "indirection" (OIND node) of X. This content can be
pointer dereference, or slice/string element. For the latter
case, the type of the OIND node should be the element type of
the slice/string. This CL fixes this. In particular, this
matters when the element type is pointerless, where the data
flow should not cause any escape.

Fixes #15730.

Change-Id: Iba9f92898681625e7e3ddef76ae65d7cd61c41e0
Reviewed-on: https://go-review.googlesource.com/107597
Reviewed-by: David Chase <drchase@google.com>
2018-04-18 02:59:37 +00:00
Daniel Martí
2b2348ab14 cmd/compile/internal/gc: add some Node methods
Focus on "isfoo" funcs that take a *Node, and conver them to isFoo
methods instead. This makes for more idiomatic Go code, and also more
readable func names.

Found candidates with grep, and applied most changes with sed. The funcs
chosen were isgoconst, isnil, and isblank. All had the same signature,
func(*Node) bool.

While at it, camelCase the isliteral and iszero function names. Don't
move these to methods, as they are only used in the backend part of gc,
which might one day be split into a separate package.

Passes toolstash -cmp on std cmd.

Change-Id: I4df081b12d36c46c253167c8841c5a841f1c5a16
Reviewed-on: https://go-review.googlesource.com/105555
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-16 00:16:55 +00:00
Cherry Zhang
5a91c83ce8 cmd/compile: in escape analysis, propagate loop depth to field
The escape analysis models "loop depth". If the address of an
expression is assigned to something defined at a lower (outer)
loop depth, the escape analysis decides it escapes. However, it
uses the loop depth of the address operator instead of where
the RHS is defined. This causes an unnecessary escape if there is
an assignment inside a loop but the RHS is defined outside the
loop. This CL propagates the loop depth.

Fixes #24730.

Change-Id: I5ff1530688bdfd90561a7b39c8be9bfc009a9dae
Reviewed-on: https://go-review.googlesource.com/105257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-04-13 14:48:23 +00:00
Alberto Donizetti
360c19157a cmd/compile: print accurate escape reason for non-const-length slices
This change makes `-m -m` print a better explanation for the case
where a slice is marked as escaping and heap-allocated because it
has a non-constant len/cap.

Fixes #24578

Change-Id: I0ebafb77c758a99857d72b365817bdba7b446cc0
Reviewed-on: https://go-review.googlesource.com/102895
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2018-03-28 16:56:03 +00:00
Matthew Dempsky
50921bfa2e cmd/compile: change unsafeUintptrTag from var to const
Change-Id: Ie30878199e24cce5b75428e6b602c017ebd16642
Reviewed-on: https://go-review.googlesource.com/102175
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2018-03-22 19:38:06 +00:00
Matthew Dempsky
eb3c44b2c4 cmd/compile: cleanup closure.go
The main thing is we now eagerly create the ODCLFUNC node for
closures, immediately cross-link them, and assign fields (e.g., Nbody,
Dcl, Parents, Marks) directly on the ODCLFUNC (previously they were
assigned on the OCLOSURE and later moved to the ODCLFUNC).

This allows us to set Curfn to the ODCLFUNC instead of the OCLOSURE,
which makes things more consistent with normal function declarations.
(Notably, this means Cvars now hang off the ODCLFUNC instead of the
OCLOSURE.)

Assignment of xfunc symbol names also now happens before typechecking
their body, which means debugging output now provides a more helpful
name than "<S>".

In golang.org/cl/66810, we changed "x := y" statements to avoid
creating false closure variables for x, but we still create them for
struct literals like "s{f: x}". Update comment in capturevars
accordingly.

More opportunity for cleanups still, but this makes some substantial
progress, IMO.

Passes toolstash-check.

Change-Id: I65a4efc91886e3dcd1000561348af88297775cd7
Reviewed-on: https://go-review.googlesource.com/100197
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-03-14 23:54:39 +00:00
Matthew Dempsky
b55eedd173 Revert "cmd/compile: cleanup nodpc and nodfp"
This reverts commit dcac984b97.

Reason for revert: broke LR architectures (arm64, ppc64, s390x)

Change-Id: I531d311c9053e81503c8c78d6cf044b318fc828b
Reviewed-on: https://go-review.googlesource.com/99695
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-03-08 21:23:01 +00:00
Matthew Dempsky
dcac984b97 cmd/compile: cleanup nodpc and nodfp
Instead of creating a new &nodfp expression for every recover() call,
or a new nodpc variable for every function instrumented by the race
detector, this CL introduces two new uintptr-typed pseudo-variables
callerSP and callerPC. These pseudo-variables act just like calls to
the runtime's getcallersp() and getcallerpc() functions.

For consistency, change runtime.gorecover's builtin stub's parameter
type from "*int32" to "uintptr".

Passes toolstash-check, but toolstash-check -race fails because of
register allocator changes.

Change-Id: I985d644653de2dac8b7b03a28829ad04dfd4f358
Reviewed-on: https://go-review.googlesource.com/99416
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-08 18:22:29 +00:00
Matthew Dempsky
e3127f023f cmd/compile: fuse escape analysis parameter tagging loops
Simplifies the code somewhat and allows removing Param.Field.

Passes toolstash-check.

Change-Id: Id854416aea8afd27ce4830ff0f5ff940f7353792
Reviewed-on: https://go-review.googlesource.com/99336
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-08 18:21:52 +00:00
Matthew Dempsky
88466e93a4 cmd/compile: mark anonymous receiver parameters as non-escaping
This was already done for normal parameters, and the same logic
applies for receiver parameters too.

Updates #24305.

Change-Id: Ia2a46f68d14e8fb62004ff0da1db0f065a95a1b7
Reviewed-on: https://go-review.googlesource.com/99335
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-08 00:20:01 +00:00
Cherry Zhang
beeab6ac02 cmd/compile: fix go:uintptrescapes tag for unnamed parameters
The tag was overwritten by the code for special handling unnamed
parameters.

Fixes #23045.

Change-Id: Ie2e1db3e902a07a2bbbc2a3424cea300f0a42cc3
Reviewed-on: https://go-review.googlesource.com/82775
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-14 21:41:39 +00:00
Cherry Zhang
dbb1d198ab cmd/compile: fix loop depth of range expression in escape analysis
ORANGE node's Right node is the expression it is ranging over,
which is evaluated before the loop. In the escape analysis,
we should walk this node without loop depth incremented.

Fixes #21709.

Change-Id: Idc1e4c76e39afb5a344d85f6b497930a488ce5cf
Reviewed-on: https://go-review.googlesource.com/80740
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-11-30 13:45:18 +00:00
Cherry Zhang
4fbf54fa0a cmd/compile: fix comment that -N does not disable escape analysis
-N does not disable escape analysis. Remove the outdated comment.

Change-Id: I96978b3afd51324b7b4f8035cf4417fb2eac4ebc
Reviewed-on: https://go-review.googlesource.com/79015
Reviewed-by: David Chase <drchase@google.com>
2017-11-21 18:09:37 +00:00
Matthew Dempsky
8684534321 cmd/compile: don't export unreachable inline method bodies
Previously, anytime we exported a function or method declaration
(which includes methods for every type transitively exported), we
included the inline function bodies, if any. However, in many cases,
it's impossible (or at least very unlikely) for the importing package
to call the method.

For example:

    package p
    type T int
    func (t T) M() { t.u() }
    func (t T) u() {}
    func (t T) v() {}

T.M and T.u are inlineable, and they're both reachable through calls
to T.M, which is exported. However, t.v is also inlineable, but cannot
be reached.

Exception: if p.T is embedded in another type q.U, p.T.v will be
promoted to q.U.v, and the generated wrapper function could have
inlined the call to p.T.v. However, in practice, this doesn't happen,
and a missed inlining opportunity doesn't affect correctness.

To implement this, this CL introduces an extra flood fill pass before
exporting to mark inline bodies that are actually reachable, so the
exporter can skip over methods like t.v.

This reduces Kubernetes build time (as measured by "time go build -a
k8s.io/kubernetes/cmd/...") on an HP Z620 measurably:

    == before ==
    real    0m44.658s
    user    11m19.136s
    sys     0m53.844s

    == after ==
    real    0m41.702s
    user    10m29.732s
    sys     0m50.908s

It also significantly cuts down the cost of enabling mid-stack
inlining (-l=4):

    == before (-l=4) ==
    real    1m19.236s
    user    20m6.528s
    sys     1m17.328s

    == after (-l=4) ==
    real    0m59.100s
    user    13m12.808s
    sys     0m58.776s

Updates #19348.

Change-Id: Iade58233ca42af823a1630517a53848b5d3c7a7e
Reviewed-on: https://go-review.googlesource.com/74110
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-31 19:12:51 +00:00
Daniel Martí
006bc57095 cmd/compile: clean up various bits of code
* replace a copy of IsMethod with a call of it.
* a few more switches where they simplify the code.
* prefer composite literals over "n := new(...); n.x = y; ...".
* use defers to get rid of three goto labels.
* rewrite updateHasCall into two funcs to remove gotos.

Passes toolstash-check on std cmd.

Change-Id: Icb5442a89a87319ef4b640bbc5faebf41b193ef1
Reviewed-on: https://go-review.googlesource.com/72070
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-22 15:50:50 +00:00
Daniel Martí
bb45bc27b5 cmd/compile: make more use of value switches
Use them to replace if/else chains with at least three comparisons,
where the code becomes clearly simpler.

Passes toolstash -cmp on std cmd.

Change-Id: Ic98aa3905944ddcab5aef5f9d9ba376853263d94
Reviewed-on: https://go-review.googlesource.com/70934
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-16 19:59:24 +00:00
Hajime Hoshi
7537bb7b30 cmd/compile/internal/gc: unexport global constants
Change-Id: Ib292ef3b0a31b2c7bdd77519324362667f30389c
Reviewed-on: https://go-review.googlesource.com/44393
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-23 20:11:30 +00:00
Josh Bleecher Snyder
2dd1f87d38 cmd/compile: add Type.NumResults and friends
Passes toolstash-check.

Change-Id: Id62bacff13fbd30de62b925d97a4e7bee1c66120
Reviewed-on: https://go-review.googlesource.com/59331
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-08-28 22:42:57 +00:00
Daniel Martí
3366f51544 cmd/compile: tweaks to unindent some code
Prioritized the chunks of code with 8 or more levels of indentation.
Basically early breaks/returns and joining nested ifs.

Change-Id: I6817df1303226acf2eb904a29f2db720e4f7427a
Reviewed-on: https://go-review.googlesource.com/55630
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-08-17 07:57:19 +00:00
Alessandro Arzilli
6f83b75be2 cmd/compile: fix lexical scope of escaped variables
When a local variable is moved to the heap the declaration position
should be preserved so that later on we can assign it to the correct
DW_TAG_lexical_block.

Fixes #20959

Change-Id: I3700ef53c68ccd506d0633f11374ad88a52b2898
Reviewed-on: https://go-review.googlesource.com/47852
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-07-10 20:09:00 +00:00
Josh Bleecher Snyder
fc08a19cef cmd/compile: move Used from gc.Node to gc.Name
Node.Used was written to from the backend
concurrently with reads of Node.Class
for the same ONAME Nodes.
I do not know why it was not failing consistently
under the race detector, but it is a race.

This is likely also a problem with Node.HasVal and Node.HasOpt.
They will be handled in a separate CL.

Fix Used by moving it to gc.Name and making it a separate bool.
There was one non-Name use of Used, marking OLABELs as used.
That is no longer needed, now that goto and label checking
happens early in the front end.

Leave the getters and setters in place,
to ease changing the representation in the future
(or changing to an interface!).

Updates #20144

Change-Id: I9bec7c6d33dcb129a4cfa9d338462ea33087f9f7
Reviewed-on: https://go-review.googlesource.com/42015
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-27 22:58:13 +00:00
Josh Bleecher Snyder
fcee3777fd cmd/compile: move addrescapes and moveToHeap to esc.go
They were used only in esc.go. 100% code movement.

Also, remove the rather outdated comment at the top of gen.go.
It's not really clear what gen.go is for any more.

Change-Id: Iaedfe7015ef6f5c11c49f3e6721b15d779a00faa
Reviewed-on: https://go-review.googlesource.com/41971
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-27 19:08:20 +00:00
Josh Bleecher Snyder
386765afdf cmd/compile: move Node.Class to flags
Put it at position zero, since it is fairly hot.

This shrinks gc.Node into a smaller size class on 64 bit systems.

name        old time/op       new time/op       delta
Template          193ms ± 5%        192ms ± 3%    ~     (p=0.353 n=94+93)
Unicode          86.1ms ± 5%       85.0ms ± 4%  -1.23%  (p=0.000 n=95+98)
GoTypes           546ms ± 3%        544ms ± 4%  -0.40%  (p=0.007 n=94+97)
Compiler          2.56s ± 3%        2.54s ± 3%  -0.67%  (p=0.000 n=99+97)
SSA               5.13s ± 2%        5.10s ± 3%  -0.55%  (p=0.000 n=94+98)
Flate             122ms ± 6%        121ms ± 4%  -0.75%  (p=0.002 n=97+95)
GoParser          144ms ± 5%        144ms ± 4%    ~     (p=0.298 n=98+97)
Reflect           348ms ± 4%        349ms ± 4%    ~     (p=0.350 n=98+97)
Tar               105ms ± 5%        104ms ± 5%    ~     (p=0.154 n=96+98)
XML               200ms ± 5%        198ms ± 4%  -0.71%  (p=0.015 n=97+98)
[Geo mean]        330ms             328ms       -0.52%

name        old user-time/op  new user-time/op  delta
Template          229ms ±11%        224ms ± 7%  -2.16%  (p=0.001 n=100+87)
Unicode           109ms ± 5%        109ms ± 6%    ~     (p=0.897 n=96+91)
GoTypes           712ms ± 4%        709ms ± 4%    ~     (p=0.085 n=96+98)
Compiler          3.41s ± 3%        3.36s ± 3%  -1.43%  (p=0.000 n=98+98)
SSA               7.46s ± 3%        7.31s ± 3%  -2.02%  (p=0.000 n=100+99)
Flate             145ms ± 6%        143ms ± 6%  -1.11%  (p=0.001 n=99+97)
GoParser          177ms ± 5%        176ms ± 5%  -0.78%  (p=0.018 n=95+95)
Reflect           432ms ± 7%        435ms ± 9%    ~     (p=0.296 n=100+100)
Tar               121ms ± 7%        121ms ± 5%    ~     (p=0.072 n=100+95)
XML               241ms ± 4%        239ms ± 5%    ~     (p=0.085 n=97+99)
[Geo mean]        413ms             410ms       -0.73%

name        old alloc/op      new alloc/op      delta
Template         38.4MB ± 0%       37.7MB ± 0%  -1.85%  (p=0.008 n=5+5)
Unicode          30.1MB ± 0%       28.8MB ± 0%  -4.09%  (p=0.008 n=5+5)
GoTypes           112MB ± 0%        110MB ± 0%  -1.69%  (p=0.008 n=5+5)
Compiler          470MB ± 0%        461MB ± 0%  -1.91%  (p=0.008 n=5+5)
SSA              1.13GB ± 0%       1.11GB ± 0%  -1.70%  (p=0.008 n=5+5)
Flate            25.0MB ± 0%       24.6MB ± 0%  -1.67%  (p=0.008 n=5+5)
GoParser         31.6MB ± 0%       31.1MB ± 0%  -1.66%  (p=0.008 n=5+5)
Reflect          77.1MB ± 0%       75.8MB ± 0%  -1.69%  (p=0.008 n=5+5)
Tar              26.3MB ± 0%       25.7MB ± 0%  -2.06%  (p=0.008 n=5+5)
XML              41.9MB ± 0%       41.1MB ± 0%  -1.93%  (p=0.008 n=5+5)
[Geo mean]       73.5MB            72.0MB       -2.03%

name        old allocs/op     new allocs/op     delta
Template           383k ± 0%         383k ± 0%    ~     (p=0.690 n=5+5)
Unicode            343k ± 0%         343k ± 0%    ~     (p=0.841 n=5+5)
GoTypes           1.16M ± 0%        1.16M ± 0%    ~     (p=0.310 n=5+5)
Compiler          4.43M ± 0%        4.42M ± 0%  -0.17%  (p=0.008 n=5+5)
SSA               9.85M ± 0%        9.85M ± 0%    ~     (p=0.310 n=5+5)
Flate              236k ± 0%         236k ± 1%    ~     (p=0.841 n=5+5)
GoParser           320k ± 0%         320k ± 0%    ~     (p=0.421 n=5+5)
Reflect            988k ± 0%         987k ± 0%    ~     (p=0.690 n=5+5)
Tar                252k ± 0%         251k ± 0%    ~     (p=0.095 n=5+5)
XML                399k ± 0%         399k ± 0%    ~     (p=1.000 n=5+5)
[Geo mean]         741k              740k       -0.07%

Change-Id: I9e952b58a98e30a12494304db9ce50d0a85e459c
Reviewed-on: https://go-review.googlesource.com/41797
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
2017-04-26 16:58:33 +00:00
Josh Bleecher Snyder
30940e2cc2 cmd/compile: move Linksym, linksymname, and isblanksym to types package
Response to code review feedback on CL 40693.

This CL was prepared by:

(1) manually adding new implementations and the Ctxt var to package types

(2) running eg with template:

func before(s *types.Sym) *obj.LSym { return gc.Linksym(s) }
func after(s *types.Sym) *obj.LSym  { return s.Linksym() }

(3) running gofmt -r:

gofmt -r 'isblanksym(a) -> a.IsBlank()'

(4) manually removing old implementations from package gc

Passes toolstash-check.

Change-Id: I39c35def7cae5bcbcc7c77253e5d2b066b981dea
Reviewed-on: https://go-review.googlesource.com/41302
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-04-21 16:10:29 +00:00
Josh Bleecher Snyder
dffe5ac9f2 cmd/compile: eliminate dead code in if statements after typechecking
This is a more thorough and cleaner fix
than doing dead code elimination separately
during inlining, escape analysis, and export.

Unfortunately, it does add another full walk of the AST.
The performance impact is very small, but not non-zero.

If a label or goto is present in the dead code, it is not eliminated.
This restriction can be removed once label/goto checking occurs
much earlier in the compiler. In practice, it probably doesn't
matter much.

Updates #19699
Fixes #19705

name       old alloc/op      new alloc/op      delta
Template        39.2MB ± 0%       39.3MB ± 0%  +0.28%  (p=0.008 n=5+5)
Unicode         29.8MB ± 0%       29.8MB ± 0%    ~     (p=1.000 n=5+5)
GoTypes          113MB ± 0%        113MB ± 0%  -0.55%  (p=0.008 n=5+5)
SSA             1.25GB ± 0%       1.25GB ± 0%  +0.02%  (p=0.008 n=5+5)
Flate           25.3MB ± 0%       25.3MB ± 0%  -0.24%  (p=0.032 n=5+5)
GoParser        31.7MB ± 0%       31.8MB ± 0%  +0.31%  (p=0.008 n=5+5)
Reflect         78.2MB ± 0%       78.3MB ± 0%    ~     (p=0.421 n=5+5)
Tar             26.6MB ± 0%       26.7MB ± 0%  +0.21%  (p=0.008 n=5+5)
XML             42.2MB ± 0%       42.2MB ± 0%    ~     (p=0.056 n=5+5)

name       old allocs/op     new allocs/op     delta
Template          385k ± 0%         387k ± 0%  +0.51%  (p=0.016 n=5+5)
Unicode           321k ± 0%         321k ± 0%    ~     (p=1.000 n=5+5)
GoTypes          1.14M ± 0%        1.14M ± 0%    ~     (p=1.000 n=5+5)
SSA              9.71M ± 0%        9.72M ± 0%  +0.10%  (p=0.008 n=5+5)
Flate             234k ± 1%         234k ± 1%    ~     (p=0.690 n=5+5)
GoParser          315k ± 0%         317k ± 0%  +0.71%  (p=0.008 n=5+5)
Reflect           980k ± 0%         983k ± 0%  +0.30%  (p=0.032 n=5+5)
Tar               251k ± 0%         252k ± 0%  +0.55%  (p=0.016 n=5+5)
XML               392k ± 0%         393k ± 0%  +0.30%  (p=0.008 n=5+5)

Change-Id: Ia10ff4bbf5c6eae782582cc9cbc9785494d4fb83
Reviewed-on: https://go-review.googlesource.com/38773
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-18 17:13:30 +00:00
Robert Griesemer
f68f292820 cmd/compile: factor out Pkg, Sym, and Type into package types
- created new package cmd/compile/internal/types
- moved Pkg, Sym, Type to new package
- to break cycles, for now we need the (ugly) types/utils.go
  file which contains a handful of functions that must be installed
  early by the gc frontend
- to break cycles, for now we need two functions to convert between
  *gc.Node and *types.Node (the latter is a dummy type)
- adjusted the gc's code to use the new package and the conversion
  functions as needed
- made several Pkg, Sym, and Type methods functions as needed
- renamed constructors typ, typPtr, typArray, etc. to types.New,
  types.NewPtr, types.NewArray, etc.

Passes toolstash-check -all.

Change-Id: I8adfa5e85c731645d0a7fd2030375ed6ebf54b72
Reviewed-on: https://go-review.googlesource.com/39855
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-07 03:04:00 +00:00
Matthew Dempsky
385c13cf18 cmd/compile/internal/gc: remove a bunch of uses of iterField
Passes toolstash-check -all.

Change-Id: I9fb91dd78dff149b5e1e1329d00855fd41f12523
Reviewed-on: https://go-review.googlesource.com/39796
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-04-06 23:08:54 +00:00
David Chase
24e94766c0 cmd/compile: added special case for reflect header fields to esc
The uintptr-typed Data field in reflect.SliceHeader and
reflect.StringHeader needs special treatment because it is
really a pointer.  Add the special treatment in walk for
bug #19168 to escape analysis.

Includes extra debugging that was helpful.

Fixes #19743.

Change-Id: I6dab5002f0d436c3b2a7cdc0156e4fc48a43d6fe
Reviewed-on: https://go-review.googlesource.com/38738
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-29 17:39:59 +00:00
Matthew Dempsky
3a89065c6c cmd/compile: replace nod(ONAME) with newname
Passes toolstash-check -all.

Change-Id: Ib9f969e5ecc1537b7eab186dc4fd504a50f800f2
Reviewed-on: https://go-review.googlesource.com/38586
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-24 23:32:09 +00:00
Keith Randall
a69754e30c cmd/compile: unnamed parameters do not escape
Fixes #19687

Change-Id: I2e4769b4ec5812506df4ac5dc6bc6a7c5774ecb0
Reviewed-on: https://go-review.googlesource.com/38600
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-03-24 17:14:00 +00:00
Martin Möhrmann
2805d20689 cmd/compile: replace all uses of ptrto by typPtr
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>
2017-03-19 14:29:53 +00:00
Matthew Dempsky
ccae744f80 cmd/compile/internal/gc: better loop var names in esc.go
Used gorename.

Change-Id: Ib33305dc95876ec18e2473ad2999788a32eb21c0
Reviewed-on: https://go-review.googlesource.com/38146
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-03-14 16:12:11 +00:00