(Because that's what the assembly files actually say - no $ on the constant.)

Change-Id: Idb774cdca0e089c4ac24ab665e23290bf7b565bf
Reviewed-on: https://go-review.googlesource.com/6895Reviewed-by: Rob Pike <r@golang.org>

Nothing uses it, nothing should start using it.
Stop leaving plausible-looking values there.
It would be nice to remove entirely, but that would
require a new version number for the object file format,
in order not to break external readers like debug/gosym.
It's easier to leave and poison.

I came across an old mail thread suggesting we start using it
to speed up tracebacks. I want to make sure that doesn't happen.

(The values there were never quite right, and the number is
fundamentally PC-specific anyway.)

Change-Id: Iaf38e8a6b523cbae30b69c28497c4588ef397519
Reviewed-on: https://go-review.googlesource.com/6890Reviewed-by: Minux Ma <minux@golang.org>

Make cmd/internal/obj/x86 support 32-bit mode and use
instead of cmd/internal/obj/i386. Delete cmd/internal/obj/i386.

Clean up encoding of PINSRQ, CMPSD to use explicit third arg
instead of jamming it into an unused slot of a different arg.

Also fix bug in old6a, which declared the wrong grammar.
The accepted (and encoded) arguments to CMPSD etc are mem,reg not reg,mem.
Code that did try to use mem,reg before would be rejected by liblink,
so only reg,reg ever worked, so existing code is not affected.
After this change, code can use mem,reg successfully.

The real bug here is that the encoding tables inverted the argument
order, making the comparisons all backward from what they say on the page.
It's too late to swap them, though: people have already written code that
expects the inverted comparisons (like in package math, and likely externally).
The best we can do is make the argument that should and can take a
memory operand accept it.

Bit-for-bit compatibility checked against tree without this CL.

Change-Id: Ife5685bc98c95001f64407f35066b34b4dae11c1
Reviewed-on: https://go-review.googlesource.com/6810Reviewed-by: Rob Pike <r@golang.org>

Add unused (but initialized) from3 field to ytab, f3t to movtab.
Remove level of indentation in movtab processing.

Change-Id: I8475988f46b541ecaccf8d34608da8bef7d12e24
Reviewed-on: https://go-review.googlesource.com/6892Reviewed-by: Rob Pike <r@golang.org>

Node.Needzero only has two values and acts as a bool, so make it a bool.

Change-Id: Ica46e5ebafbe478017ea52ce6bb335f404059677
Reviewed-on: https://go-review.googlesource.com/6800Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #10066.

Change-Id: I43c423793dd094989e921e163a06b12181a35719
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/6750
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Chris Manghane <cmang@golang.org>

Change-Id: I520a0f2c2d14f744a5d2e8cf93963eec1cf3e9ba
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/6732Reviewed-by: Andrew Gerrand <adg@golang.org>

This avoids repeated allocation and map lookups
when constructing the pcln tables.

For 6g compiling cmd/internal/gc/*.go this saves about 8% wall time.

Change-Id: I6a1a80e278ae2c2a44bd1537015ea7b4e7a4d6ca
Reviewed-on: https://go-review.googlesource.com/6793Reviewed-by: Rob Pike <r@golang.org>

Remove blank lines and merge lone imports into blocks.

Change-Id: Ib46dad584456909969f1ba3a2c7f5667abf336ae
Reviewed-on: https://go-review.googlesource.com/6792Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Change-Id: I764933f4928bb9d0d119fbfe44a193ce1449b61e
Reviewed-on: https://go-review.googlesource.com/6791Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Change-Id: Ib813eb5960c3310b1c919f25f687560f4f9d63b0
Reviewed-on: https://go-review.googlesource.com/6820Reviewed-by: Russ Cox <rsc@golang.org>

For OSes that use elf on intel, 2*Ptrsize bytes are reserved for TLS.
But only one pointer (g) has been stored in the TLS for a while now.
So we can set it to just Ptrsize, which happily matches what happens
when externally linking.

Fixes #9913

Change-Id: Ic816369d3a55a8cdcc23be349b1a1791d53f5f81
Reviewed-on: https://go-review.googlesource.com/6584
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Accidental semantics change in 4c6364a8.

Change-Id: I0bbfc441662d79af4dbac6f9fc4e3a485adfb924
Reviewed-on: https://go-review.googlesource.com/6831Reviewed-by: Minux Ma <minux@golang.org>

Change-Id: I83de9d83708edc8d196bbcfdc7d2ba7ffaff50d2
Reviewed-on: https://go-review.googlesource.com/6586Reviewed-by: Rob Pike <r@golang.org>

Fixes #10072

Change-Id: I1f73c8829a89144d49433a36a4e64223c74af954
Reviewed-on: https://go-review.googlesource.com/6585Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Ice4f78e74ec3025a974ffd9ca5e3d28bb3164f40
Reviewed-on: https://go-review.googlesource.com/6794Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Run-TryBot: David Crawshaw <crawshaw@golang.org>

Change-Id: Id1927180ecd18b849727225adea05465d36b3973
Reviewed-on: https://go-review.googlesource.com/6210Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>

This is an experiment to see if removing the boundary bit logic will
lead to fewer cache misses and improved performance. Instead of using
boundary bits we use the span information to get element size and use
some bit whacking to get the boundary without having to touch the
random heap bits which cause cache misses.

Furthermore once the boundary bit is removed we can either use that
bit for a simpler checkmark routine or we can reduce the number of
bits in the GC bitmap to 2 bits per pointer sized work. For example
the 2 bits at the boundary can be used for marking and pointer/scalar
differentiation. Since we don't need the mark bit except at the
boundary nibble of the object other nibbles can use this bit
as a noscan bit to indicate that there are no more pointers in
the object.

Currently the changed included in this CL slows down the garbage
benchmark. With the boundary bits garbage gives 5.78 and without
(this CL) it gives 5.88 which is a 2% slowdown.

Change-Id: Id68f831ad668176f7dc9f7b57b339e4ebb6dc4c2
Reviewed-on: https://go-review.googlesource.com/6665Reviewed-by: Austin Clements <austin@google.com>

Change-Id: I932c2f1b1d27c437722cd27d2001b085a655c572
Reviewed-on: https://go-review.googlesource.com/6722Reviewed-by: Alan Donovan <adonovan@google.com>

Change-Id: Ide0615542d67b7d81bf6c56aab550e142a8789f7
Reviewed-on: https://go-review.googlesource.com/6682Reviewed-by: Alan Donovan <adonovan@google.com>

Change-Id: If04840c34b0ac5168ce1699eae880f04ae21c84c
Reviewed-on: https://go-review.googlesource.com/6680Reviewed-by: Alan Donovan <adonovan@google.com>

Shifts are trivially implemented by combining
Float.MantExp and Float.SetMantExp.

Change-Id: Ia2fb49297d8ea7aa7d64c8b1318dc3dc7c8af2f7
Reviewed-on: https://go-review.googlesource.com/6671Reviewed-by: Alan Donovan <adonovan@google.com>

This change represents Accuracy as a bit pattern rather than
an ordered value; with a new value Undef which is both Below
and Above.

Change-Id: Ibb96294c1417fb3cf2c3cf2374c993b0a4e106b3
Reviewed-on: https://go-review.googlesource.com/6650Reviewed-by: Alan Donovan <adonovan@google.com>

Change-Id: I9a6ebb747d5b9756c214bdeb19f60820602d7a24
Reviewed-on: https://go-review.googlesource.com/6340Reviewed-by: Alan Donovan <adonovan@google.com>

This change introduces NaNs (for situations like Inf-Inf, etc.).
The implementation is incomplete (the four basic operations produce
a NaN if any of the operands is an Inf or a NaN); and some operations
produce incorrect accuracy for NaN arguments. These are known bugs
which are documented.

Change-Id: Ia88841209e47930681cef19f113e178f92ceeb33
Reviewed-on: https://go-review.googlesource.com/6540Reviewed-by: Alan Donovan <adonovan@google.com>

These benchmarks show the effect of the combination of this change
and Rick's pending CL 6665. Code with interior pointers is helped
much more than code without, but even code without doesn't suffer
too badly.

benchmark                          old ns/op      new ns/op      delta
BenchmarkBinaryTree17              6989407768     6851728175     -1.97%
BenchmarkFannkuch11                4416250775     4405762558     -0.24%
BenchmarkFmtFprintfEmpty           134            130            -2.99%
BenchmarkFmtFprintfString          491            402            -18.13%
BenchmarkFmtFprintfInt             430            420            -2.33%
BenchmarkFmtFprintfIntInt          748            663            -11.36%
BenchmarkFmtFprintfPrefixedInt     602            534            -11.30%
BenchmarkFmtFprintfFloat           728            699            -3.98%
BenchmarkFmtManyArgs               2528           2507           -0.83%
BenchmarkGobDecode                 17448191       17749756       +1.73%
BenchmarkGobEncode                 14579824       14370183       -1.44%
BenchmarkGzip                      656489990      652669348      -0.58%
BenchmarkGunzip                    141254147      141099278      -0.11%
BenchmarkHTTPClientServer          94111          93738          -0.40%
BenchmarkJSONEncode                36305013       36696440       +1.08%
BenchmarkJSONDecode                124652000      128176454      +2.83%
BenchmarkMandelbrot200             6009333        5997093        -0.20%
BenchmarkGoParse                   7651583        7623494        -0.37%
BenchmarkRegexpMatchEasy0_32       213            213            +0.00%
BenchmarkRegexpMatchEasy0_1K       511            494            -3.33%
BenchmarkRegexpMatchEasy1_32       186            187            +0.54%
BenchmarkRegexpMatchEasy1_1K       1834           1827           -0.38%
BenchmarkRegexpMatchMedium_32      427            412            -3.51%
BenchmarkRegexpMatchMedium_1K      154841         153086         -1.13%
BenchmarkRegexpMatchHard_32        7473           7478           +0.07%
BenchmarkRegexpMatchHard_1K        233587         232272         -0.56%
BenchmarkRevcomp                   918797689      944528032      +2.80%
BenchmarkTemplate                  167665081      167773121      +0.06%
BenchmarkTimeParse                 631            636            +0.79%
BenchmarkTimeFormat                672            666            -0.89%

Change-Id: Ia923de3cdb3993b640fe0a02cbe2c7babc16f32c
Reviewed-on: https://go-review.googlesource.com/6782Reviewed-by: Rick Hudson <rlh@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Gc already calculates n as an int, so converting to int64 to call
growslice doesn't serve any purpose except to emit slightly larger
code on 32-bit platforms.  Passing n as an int shrinks godoc's text
segment by 8kB (9472633 => 9464133) when building for ARM.

Change-Id: Ief9492c21d01afcb624d3f2a484df741450b788d
Reviewed-on: https://go-review.googlesource.com/6231Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

SHRQ CX, DX:AX is changing to SHRQ CX, AX, DX.
This is the first step: using SHRQ From=CX, From3=AX, To=DX
as the preferred encoding.
Once the assemblers and 6g have been updated,
support for the old encoding can be removed.

Change-Id: Ie603fb8ac25a6df78e42f7ddcae078a7684a7c26
Reviewed-on: https://go-review.googlesource.com/6693Reviewed-by: Rob Pike <r@golang.org>

The unbounded list-based defer pool can grow infinitely.
This can happen if a goroutine routinely allocates a defer;
then blocks on one P; and then unblocked, scheduled and
frees the defer on another P.
The scenario was reported on golang-nuts list.

We've been here several times. Any unbounded local caches
are bad and grow to infinite size. This change introduces
central defer pool; local pools become fixed-size
with the only purpose of amortizing accesses to the
central pool.

Freedefer now executes on system stack to not consume
nosplit stack space.

Change-Id: I1a27695838409259d1586a0adfa9f92bccf7ceba
Reviewed-on: https://go-review.googlesource.com/3967Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>

The unbounded list-based sudog cache can grow infinitely.
This can happen if a goroutine is routinely blocked on one P
and then unblocked and scheduled on another P.
The scenario was reported on golang-nuts list.

We've been here several times. Any unbounded local caches
are bad and grow to infinite size. This change introduces
central sudog cache; local caches become fixed-size
with the only purpose of amortizing accesses to the
central cache.

The change required to move sudog cache from mcache to P,
because mcache is not scanned by GC.

Change-Id: I3bb7b14710354c026dcba28b3d3c8936a8db4e90
Reviewed-on: https://go-review.googlesource.com/3742Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>

The original C code is: (x->type & SHIDDEN) ? 2 : 0, however when
cleaning up the code for c2go, the ternary operator is rewritten in
the exact opposite way.

We need a test for this, and that's being tracked as #10070.

Fixes #10067.

Change-Id: I24a5e021597d8bc44218c6e75bab6446513b76cf
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/6730Reviewed-by: Ian Lance Taylor <iant@golang.org>

The creation of liblink and subsequent introduction of more explicit
TLS handling broke 6l's (unsupported) -shared flag.  This change adds
-shared flags to cmd/asm and 6g and changes liblink to generate shared-
library compatible instruction sequences when they are passed, and
changes 6l to emit the appropriate ELF relocation.

A proper fix probably also requires go tool changes.

Fixes #9652.

Change-Id: I7b7718fe7305c802ac994f4a5c8de68cfbe6c76b
Reviewed-on: https://go-review.googlesource.com/4321Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes the linux-amd64-nocgo builder.

Regression from https://golang.org/cl/6531

Change-Id: Ibffd1ecfee4a888605ed54196f53956ae42e591c
Reviewed-on: https://go-review.googlesource.com/6700Reviewed-by: Andrew Gerrand <adg@golang.org>

Change-Id: I01e328fc3644b679bacf2209c3d7ade9d8bffe53
Reviewed-on: https://go-review.googlesource.com/6551Reviewed-by: Rob Pike <r@golang.org>

cmd/asm/internal/asm no longer imports obj/$GOARCH, only obj itself.

Change-Id: I7c0d107524d833b4a1b6e6a497cca4addadee570
Reviewed-on: https://go-review.googlesource.com/6670Reviewed-by: Russ Cox <rsc@golang.org>

The name g is an alias for R10 and R30, respectively. Have Rconv
print the alias, for consistency with the input language.

Change-Id: Ic3f40037884a0c8de5089d8c8a8efbcdc38c0d56
Reviewed-on: https://go-review.googlesource.com/6630Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

This will enable test sharding over multiple VMs, to speed trybot answers.

Update #10029

Change-Id: Ie277c6459bc38005e4d6af14d22effeaa0a4667e
Reviewed-on: https://go-review.googlesource.com/6531Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

Issue #10043

Change-Id: I6ce7f303cd96ac575f7a673dd4a459339382d22e
Reviewed-on: https://go-review.googlesource.com/6692Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We now wait until we see the completed prompt from a command before
proceeding. This seems to cut down on a spurious error I have seen
this afternoon.

Change-Id: Ic0a3481d8c265c3c3b4449ec7ac1c2752b85b0b6
Reviewed-on: https://go-review.googlesource.com/6691Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>

Just a missed case in in the handling of branches.

Fixes #10065

Change-Id: I6be054d30bf1f383c12b4c7626abd5f8ae22b22e
Reviewed-on: https://go-review.googlesource.com/6631Reviewed-by: Minux Ma <minux@golang.org>