This is really moving all the non-lexer pieces out of lex.go
into main.go. It's always been confusing that the top-most
compiler entry point (Main) is in the same file with the
lexer. Both files remain of substantial size (> 1000 lines),
which justifies this even more.

No other changes.

Change-Id: I03895589d5e3cc2340580350bbc1420539893dfc
Reviewed-on: https://go-review.googlesource.com/20601
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Id041c1b2d364aecd7a6613a53237f7de2c650a7e
Reviewed-on: https://go-review.googlesource.com/20599
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #14740

Change-Id: Iad8d971c21977b0a1f4ef55a08bb180a8125e976
Reviewed-on: https://go-review.googlesource.com/20562Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Removes an intermediate layer of functions that was clogging up a
corner of the compiler's profile graph.

I can't measure a performance improvement running a large build
like jujud, but the profile reports less total time spent in
gc.(*lexer).getr.

Change-Id: I3000585cfcb0f9729d3a3859e9023690a6528591
Reviewed-on: https://go-review.googlesource.com/20565Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

In addition to reflect.Value.Call, exported methods can be invoked
by the Func value in the reflect.Method struct. This CL has the
compiler track what functions get access to a legitimate reflect.Method
struct by looking for interface calls to either of:

	Method(int) reflect.Method
	MethodByName(string) (reflect.Method, bool)

This is a little overly conservative. If a user implements a type
with one of these methods without using the underlying calls on
reflect.Type, the linker will assume the worst and include all
exported methods. But it's cheap.

No change to any of the binary sizes reported in cl/20483.

For #14740

Change-Id: Ie17786395d0453ce0384d8b240ecb043b7726137
Reviewed-on: https://go-review.googlesource.com/20489Reviewed-by: Matthew Dempsky <mdempsky@google.com>

While we're here, remove a bit of dead code.

Change-Id: I1344bb41e5d368825ca5748189382f9e7023c59a
Reviewed-on: https://go-review.googlesource.com/20596
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Use an early return. Check errors. Deduplicate.

Change-Id: Iabefd563b5ef82a16fab4791277630804fd09003
Reviewed-on: https://go-review.googlesource.com/20597
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I298b9d389ac33a24365f4c06a122c3af989906c0
Reviewed-on: https://go-review.googlesource.com/20594
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>

Might as well sort them while they're still in a slice.

Change-Id: I40c25ddc5c054dcb4da2aeefa79947967609d599
Reviewed-on: https://go-review.googlesource.com/20591
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Part 1 of optimizing the deflater. This optimizes the bitwriter by:

* Removing allocations.
* Storing compound values for bit codes instead of 2 separate tables.
* Accumulate 48 bits between writes instead of 24.
* Inline bit flushing.

This also contains code that will be used in later CL's
(writeBlockDynamic, writeBlockHuff).

Tests for Huffman bit writer encoding regressions has been added.

name                       old speed      new speed      delta
EncodeDigitsSpeed1e4-4     19.3MB/s ± 1%  21.6MB/s ± 1%  +11.77%
EncodeDigitsSpeed1e5-4     25.0MB/s ± 6%  30.7MB/s ± 1%  +22.70%
EncodeDigitsSpeed1e6-4     28.2MB/s ± 1%  32.3MB/s ± 1%  +14.64%
EncodeDigitsDefault1e4-4   13.3MB/s ± 0%  14.2MB/s ± 1%   +7.07%
EncodeDigitsDefault1e5-4   6.43MB/s ± 1%  6.64MB/s ± 1%   +3.27%
EncodeDigitsDefault1e6-4   5.81MB/s ± 0%  5.85MB/s ± 1%   +0.69%
EncodeDigitsCompress1e4-4  13.2MB/s ± 0%  14.4MB/s ± 0%   +9.10%
EncodeDigitsCompress1e5-4  6.40MB/s ± 1%  6.61MB/s ± 0%   +3.20%
EncodeDigitsCompress1e6-4  5.80MB/s ± 1%  5.90MB/s ± 1%   +1.64%
EncodeTwainSpeed1e4-4      18.4MB/s ± 1%  20.7MB/s ± 1%  +12.72%
EncodeTwainSpeed1e5-4      27.7MB/s ± 1%  31.0MB/s ± 1%  +11.78%
EncodeTwainSpeed1e6-4      29.1MB/s ± 0%  32.9MB/s ± 2%  +13.25%
EncodeTwainDefault1e4-4    12.4MB/s ± 0%  13.1MB/s ± 1%   +5.88%
EncodeTwainDefault1e5-4    7.52MB/s ± 1%  7.83MB/s ± 0%   +4.19%
EncodeTwainDefault1e6-4    7.08MB/s ± 1%  7.26MB/s ± 0%   +2.54%
EncodeTwainCompress1e4-4   12.0MB/s ± 1%  12.8MB/s ± 1%   +6.70%
EncodeTwainCompress1e5-4   5.96MB/s ± 1%  6.16MB/s ± 0%   +3.27%
EncodeTwainCompress1e6-4   5.37MB/s ± 0%  5.39MB/s ± 1%   +0.47%

>Allocations:

benchmark                              old allocs     new allocs     delta
BenchmarkEncodeDigitsSpeed1e4-4        50             0              -100.00%
BenchmarkEncodeDigitsSpeed1e5-4        110            0              -100.00%
BenchmarkEncodeDigitsSpeed1e6-4        1032           0              -100.00%
BenchmarkEncodeDigitsDefault1e4-4      56             0              -100.00%
BenchmarkEncodeDigitsDefault1e5-4      120            0              -100.00%
BenchmarkEncodeDigitsDefault1e6-4      966            0              -100.00%
BenchmarkEncodeDigitsCompress1e4-4     56             0              -100.00%
BenchmarkEncodeDigitsCompress1e5-4     120            0              -100.00%
BenchmarkEncodeDigitsCompress1e6-4     966            0              -100.00%
BenchmarkEncodeTwainSpeed1e4-4         58             0              -100.00%
BenchmarkEncodeTwainSpeed1e5-4         132            0              -100.00%
BenchmarkEncodeTwainSpeed1e6-4         1082           0              -100.00%
BenchmarkEncodeTwainDefault1e4-4       52             0              -100.00%
BenchmarkEncodeTwainDefault1e5-4       126            0              -100.00%
BenchmarkEncodeTwainDefault1e6-4       886            0              -100.00%
BenchmarkEncodeTwainCompress1e4-4      52             0              -100.00%
BenchmarkEncodeTwainCompress1e5-4      120            0              -100.00%
BenchmarkEncodeTwainCompress1e6-4      880            0              -100.00%

benchmark                              old bytes     new bytes     delta
BenchmarkEncodeDigitsSpeed1e4-4        4288          2             -99.95%
BenchmarkEncodeDigitsSpeed1e5-4        8896          15            -99.83%
BenchmarkEncodeDigitsSpeed1e6-4        84098         153           -99.82%
BenchmarkEncodeDigitsDefault1e4-4      4480          3             -99.93%
BenchmarkEncodeDigitsDefault1e5-4      9216          76            -99.18%
BenchmarkEncodeDigitsDefault1e6-4      73920         768           -98.96%
BenchmarkEncodeDigitsCompress1e4-4     4480          3             -99.93%
BenchmarkEncodeDigitsCompress1e5-4     9216          76            -99.18%
BenchmarkEncodeDigitsCompress1e6-4     73920         768           -98.96%
BenchmarkEncodeTwainSpeed1e4-4         4544          2             -99.96%
BenchmarkEncodeTwainSpeed1e5-4         9600          15            -99.84%
BenchmarkEncodeTwainSpeed1e6-4         77633         153           -99.80%
BenchmarkEncodeTwainDefault1e4-4       4352          3             -99.93%
BenchmarkEncodeTwainDefault1e5-4       9408          76            -99.19%
BenchmarkEncodeTwainDefault1e6-4       65984         768           -98.84%
BenchmarkEncodeTwainCompress1e4-4      4352          3             -99.93%
BenchmarkEncodeTwainCompress1e5-4      9216          76            -99.18%
BenchmarkEncodeTwainCompress1e6-4      65792         768           -98.83%

Updates #14258

Change-Id: Ibaa97b9619743ad623094727228eb2ada1ec7f1f
Reviewed-on: https://go-review.googlesource.com/19336Reviewed-by: Nigel Tao <nigeltao@golang.org>
Reviewed-by: Joe Tsai <joetsai@digital-static.net>
Run-TryBot: Joe Tsai <joetsai@digital-static.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This will test if deflate output is deterministic between two runs
of the deflater, when write sizes differ.

The deflater makes no official promises that results are
deterministic between runs, but this is a good test to determine
unintentional randomness.

Note that this does not guarantee that results are deterministic
across platforms nor that results will be deterministic between
Go versions. This is also not guarantees we should imply.

Change-Id: Id7dd89fe276060fd83a43d0b34ac35d50fcd32d9
Reviewed-on: https://go-review.googlesource.com/20573Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

p can be nil in Dconv so we need to do a check before dereferencing
it. Fixes a problem I was having running toolstash.

Change-Id: I34d6d278b319583d8454c2342ac88e054fc4b641
Reviewed-on: https://go-review.googlesource.com/20595Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

I don't know what they're used for, but that's the only file they're
referenced in.

Change-Id: Ie39d7d4621e2d5224408243b5789597ca0dc14be
Reviewed-on: https://go-review.googlesource.com/20593Reviewed-by: Dave Cheney <dave@cheney.net>

This code is an eye sore to keep scrolling past in subr.go, so move it
out of the way.

Change-Id: I8eafc1725d868a4924ee7ca9b7738cce309f9eff
Reviewed-on: https://go-review.googlesource.com/20592Reviewed-by: Dave Cheney <dave@cheney.net>

Still fails about 20% of the time on my laptop.

Fixes #14766.

Change-Id: I169ab728c6022dceeb91188f5ad466ed6413c062
Reviewed-on: https://go-review.googlesource.com/20590
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: If2a174f482ecd56dee43f921d13fef98439872fc
Reviewed-on: https://go-review.googlesource.com/20559Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Change-Id: Ia2273c3a9f0001d16b0c767fea91498a9acb0af5
Reviewed-on: https://go-review.googlesource.com/19963Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Use idiomatic slicing operations instead of incrementally building a
linked list.

Passes toolstash -cmp.

Change-Id: Idb0e40c7b4d7d1110d23828afa8ae1d157ba905f
Reviewed-on: https://go-review.googlesource.com/20556Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

In particular, make Alignof work more like Sizeof. Other idiomatic
cleanups while here.

Passes toolstash -cmp.

Change-Id: I4def20894f3d95e49ab6a50ddba189be36fdd258
Reviewed-on: https://go-review.googlesource.com/20555
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This could be done by threading the Iter value down through memrun and
ispaddedfield, but that ends up a bit clunky. This way is also closer
to how we'll want the code to look once fields are kept in slices.

Passes toolstash -cmp.

Change-Id: I8a44445c85f921eb18d97199df2026c5ce0f4f67
Reviewed-on: https://go-review.googlesource.com/20558
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

x86 has a lot of instructions that require the output to be in the same
register as one of the inputs.  When allocating the output register,
allocate the same register as the input if it is available.

Improves the performance of golang.org/x/crypto/sha3 by
10% (from 6% slower than 1.6 to 4% faster).

Fixes #14745

Change-Id: I4d81785240c9368e4dc75107b45c959d200df8e6
Reviewed-on: https://go-review.googlesource.com/20488Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Not calling popdcl doesn't have an impact on generated code but
the result is a growing (rather than empty) stack of symbols,
possibly causing more data to remain alive than necessary.

Also: minor cleanups.

Change-Id: Ic4fdbcd8843637d69ab1aa15e896a7e6339bc990
Reviewed-on: https://go-review.googlesource.com/20554Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>

Use a map to detect duplicate symbols. Allows eliminating an otherwise
unneeded field from Sym and gets rid of a global variable.

Change-Id: Ic004bca7e9130a1261a1cddbc17244529a2a1df4
Reviewed-on: https://go-review.googlesource.com/20552Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>

Change the existing flags from compile time consts to be configurable
from the command line.

Change-Id: I4aab4bf3dfcbdd8e2b5a2ff51af95c2543967769
Reviewed-on: https://go-review.googlesource.com/20560Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The location of VARDEFs is incorrect for PPARAMOUT variables
which are also used as temporary locations.  We put in VARDEFs
when setting the variable at return time, but when the location
is also used as a temporary the lifetime values are wrong.

Fix copyelim to update the names map properly.  This is a
real name bug fix which, as a result, allows me to
write a reasonable test to trigger the PPARAMOUT bug.

This is kind of a band-aid fix for #14591.  A more pricipled
fix (which allows values to be stored in the return variable
earlier than the return point) will be harder.

Fixes #14591

Change-Id: I7df8ae103a982d1f218ed704c080d7b83cdcfdd9
Reviewed-on: https://go-review.googlesource.com/20457Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Fixes #14759.

Change-Id: I6cef0b49ba00ab85b25ce1e7bad80ad85e2d5076
Reviewed-on: https://go-review.googlesource.com/20545
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>

PKIX versions are off-by-one, so v1 is actually a zero on the wire, v2
is a one, and so on.

The RFC says that the version in a CRL is optional, but doesn't say what
the default is. Since v2 is the only accepted version, I had made the
default v2. However, OpenSSL considers the default to be v1. Also, if
the default is v2 and the element is optional then we'll never actually
write v2 on the wire. That's contrary to the RFC which clearly assumes
that v2 will be expressed on the wire in some cases.

Therefore, this change aligns with OpenSSL and assumes that v1 is the
default CRL version.

Fixes #13931

[1] https://tools.ietf.org/html/rfc5280#section-5.1

Change-Id: Ic0f638ebdd21981d92a99a882affebf3a77ab71a
Reviewed-on: https://go-review.googlesource.com/20544Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The default version of an X.509 certificate is v1, which is encoded on
the wire as a zero.

Fixes #13382.

Change-Id: I5fd725c3fc8b08fd978ab694a3e2d6d2a495918b
Reviewed-on: https://go-review.googlesource.com/20548Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Allows safely eliminating more direct uses of Type's Type and Down
fields.

Passes toolstash -cmp.

Change-Id: I5c17fe541a0473c3cd2978d8314c4ab759079a61
Reviewed-on: https://go-review.googlesource.com/20541
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

I would like to add a

    func (t *Type) Elem() *Type

method to package gc, but that would collide with the existing

    func (t *Type) Elem() ssa.Type

method needed to make *gc.Type implement ssa.Type.  Because the latter
is much less widely used right now than the former will be, this CL
renames it to ElemType.

Longer term, hopefully gc and ssa will share a common Type interface,
and ElemType can go away.

Change-Id: I270008515dc4c01ef531cf715637a924659c4735
Reviewed-on: https://go-review.googlesource.com/20546
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Eliminate "else_clause" parameter and move error messages about bad if
statements into the if_stmt parsing method.

Passes toolstash -cmp.

Change-Id: Ibc31619bdb2e7e0cf28712b14640f7d9b6124a40
Reviewed-on: https://go-review.googlesource.com/20543
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

Change-Id: I06dedf4ebfa32b598f5545dc9354c8e4a95610b1
Reviewed-on: https://go-review.googlesource.com/20525
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #14741.

Change-Id: Idb8de8b0c1059c15e4c3df4a60bbd340d4e74aba
Reviewed-on: https://go-review.googlesource.com/20487Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

Make sure we do any just-before-return cleanup on all paths out of a
function, including when recovering.  Each exit path should include
deferreturn (if there are any defers) and then the exit
code (e.g. copying heap-escaping return values back to the stack).

Introduce a Defer SSA block type which has two outgoing edges - one the
fallthrough edge (the defer was queued successfully) and one which
immediately returns (the defer had a successful recover() call and
normal execution should resume at the return point).

Fixes #14725

Change-Id: Iad035c9fd25ef8b7a74dafbd7461cf04833d981f
Reviewed-on: https://go-review.googlesource.com/20486Reviewed-by: David Chase <drchase@google.com>

Passes toolstash -cmp.

Change-Id: I014613985005780d1a622c1981b35a94cda798bb
Reviewed-on: https://go-review.googlesource.com/20530
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I055e986c3f27d5c07badcd1684f4fe1d65a917a9
Reviewed-on: https://go-review.googlesource.com/20523
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This CL was mostly produced by a one-off automated rewrite tool
looking for statements like "for X := T.Type; X != nil; X = X.Down"
and a few minor variations.

Passes toolstash -cmp.

Change-Id: Ib22705e37d078ef97841ee2e08f60bdbcabb94ad
Reviewed-on: https://go-review.googlesource.com/20520
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Passes toolstash -cmp.

Change-Id: I05322fb5afd213f13fb247ec1a5f655c17a58774
Reviewed-on: https://go-review.googlesource.com/20522
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

That was easy.

Fixes #14473.

Change-Id: I9d1d20a5c5a9b1423e6c72c0460ee4a78130864f
Reviewed-on: https://go-review.googlesource.com/20521
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #14554.

Change-Id: I37ab4e4dc1aee84ac448d437314f8eecbbc02994
Reviewed-on: https://go-review.googlesource.com/20021Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>