Commit graph

65 commits

Author SHA1 Message Date
David Chase
897c0ebf61 cmd/compile: adapt GOSSAHASH to set a DebugTest flag in ssa.Config
Binary search remains our friend.
Suppose you add an ought-to-be-benign pattern to PPC64.rules,
and make.bash starts crashing.  You can guard the pattern(s)
with config.DebugTest:

(Eq8 x y) && config.DebugTest && isSigned(x.Type) &&
   isSigned(y.Type) ->
   (Equal (CMPW (SignExt8to32 x) (SignExt8to32 y)))

and then

  gossahash -s ./make.bash
  ...
  (go drink beer while silicon minions toil)
  ...
  Trying ./make.bash args=[], env=[GOSSAHASH=100110010111110]
  ./make.bash failed (1 distinct triggers): exit status 1
  Trigger string is 'GOSSAHASH triggered (*importReader).readByte',
    repeated 1 times
  Review GSHS_LAST_FAIL.0.log for failing run
  Finished with GOSSAHASH=100110010111110

Change-Id: I4eff46ebaf496baa2acedd32e217005cb3ac1c62
Reviewed-on: https://go-review.googlesource.com/29273
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-15 21:49:49 +00:00
Keith Randall
167e381f40 cmd/compile: make ssa compilation unconditional
Rip out the code that allows SSA to be used conditionally.

No longer exists:
 ssa=0 flag
 GOSSAHASH
 GOSSAPKG
 SSATEST

GOSSAFUNC now only controls the printing of the IR/html.

Still need to rip out all of the old backend.  It should no longer be
callable after this CL.

Update #16357

Change-Id: Ib30cc18fba6ca52232c41689ba610b0a94aa74f5
Reviewed-on: https://go-review.googlesource.com/29155
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-09-14 17:38:04 +00:00
David Chase
eed061f89c cmd/compile: enable SSA for PowerPC 64 Big-endian
It passed tests once, if anything's wrong, better to fail
sooner than later.

Change-Id: Ibb1c5db3f4c5535a4ff4681fd157db77082c5041
Reviewed-on: https://go-review.googlesource.com/28982
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-14 17:14:47 +00:00
Michael Munday
6ec993adc3 cmd/compile: add SSA backend for s390x and enable by default
The new SSA backend modifies the ABI slightly: R0 is now a usable
general purpose register.

Fixes #16677.

Change-Id: I367435ce921e0c7e79e021c80cf8ef5d1d1466cf
Reviewed-on: https://go-review.googlesource.com/28978
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-13 19:39:38 +00:00
David Crawshaw
791f71d192 cmd: use obj.GOOS, obj.GOARCH, etc
As cmd/internal/obj is coordinating the definition of GOOS, GOARCH,
etc across the compiler and linker, turn its functions into globals
and use them everywhere.

Change-Id: I5db5addda3c6b6435c37fd5581c7c3d9a561f492
Reviewed-on: https://go-review.googlesource.com/28854
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-09-09 16:38:45 +00:00
Cherry Zhang
b2e0e9688a cmd/compile: remove Zero and NilCheck for newobject
Recognize runtime.newobject and don't Zero or NilCheck it.

Fixes #15914 (?)
Updates #15390.

TBD: add test

Change-Id: Ia3bfa5c2ddbe2c27c92d9f68534a713b5ce95934
Reviewed-on: https://go-review.googlesource.com/27930
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-08-30 23:10:43 +00:00
Cherry Zhang
e71e1fe87e cmd/compile: get MIPS64 SSA working
- implement *, /, %, shifts, Zero, Move.
- fix mistakes in comparison.
- fix floating point rounding.
- handle RetJmp in assembler (which was not handled, as a consequence
  Duff's device was disabled in the old backend.)

all.bash now passes with SSA on.

Updates #16359.

Change-Id: Ia14eed0ed1176b5d800592080c8f53dded7fe73f
Reviewed-on: https://go-review.googlesource.com/27592
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-25 12:53:36 +00:00
Cherry Zhang
310a40b4f2 cmd/compile: start MIPS64 port of SSA backend
Fib with all int and float types run correctly.
*, /, shifts, Zero, Move not implemented yet. No optimization yet.

Updates #16359.

Change-Id: I4b0412954d5fd4c13a5fcddd8689ed8ac701d345
Reviewed-on: https://go-review.googlesource.com/27404
Reviewed-by: David Chase <drchase@google.com>
2016-08-22 16:30:38 +00:00
David Chase
5b9ff11c3d cmd/compile: ppc64le working, not optimized enough
This time with the cherry-pick from the proper patch of
the old CL.

Stack size increased.
Corrected NaN-comparison glitches.
Marked g register as clobbered by calls.
Fixed shared libraries.

live_ssa.go still disabled because of differences.
Presumably turning on more optimization will fix
both the stack size and the live_ssa.go glitches.

Enhanced debugging output for shared libs test.

Rebased onto master.

Updates #16010.

Change-Id: I40864faf1ef32c118fb141b7ef8e854498e6b2c4
Reviewed-on: https://go-review.googlesource.com/27159
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-08-18 16:34:47 +00:00
Cherry Zhang
1e94d79f9d cmd/compile: disable Duff's device on darwin/arm64
Darwin linker does not support BR26 reloc with non-zero addend.

Fixes #16724.

Change-Id: I1b5b4dc7159141bde3e273490f435c08c583afaf
Reviewed-on: https://go-review.googlesource.com/27081
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
2016-08-16 10:41:53 +00:00
David Chase
d08010f94e [dev.ssa] cmd/compile: PPC64, FP to/from int conversions.
Passes ssa_test.

Requires a few new instructions and some scratchpad
memory to move data between G and F registers.

Also fixed comparisons to be correct in case of NaN.
Added missing instructions for run.bash.
Removed some FP registers that are apparently "reserved"
(but that are also apparently also unused except for a
gratuitous multiplication by two when y = x+x would work
just as well).

Currently failing stack splits.

Updates #16010.

Change-Id: I73b161bfff54445d72bd7b813b1479f89fc72602
Reviewed-on: https://go-review.googlesource.com/26813
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-08-15 14:47:49 +00:00
Keith Randall
c069bc4996 [dev.ssa] cmd/compile: implement GO386=387
Last part of the 386 SSA port.

Modify the x86 backend to simulate SSE registers and
instructions with 387 registers and instructions.
The simulation isn't terribly performant, but it works,
and the old implementation wasn't very performant either.
Leaving to people who care about 387 to optimize if they want.

Turn on SSA backend for 386 by default.

Fixes #16358

Change-Id: I678fb59132620b2c47e993c1c10c4c21135f70c0
Reviewed-on: https://go-review.googlesource.com/25271
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-08-10 17:41:01 +00:00
Keith Randall
69a755b602 [dev.ssa] cmd/compile: port SSA backend to amd64p32
It's not a new backend, just a PtrSize==4 modification
of the existing AMD64 backend.

Change-Id: Icc63521a5cf4ebb379f7430ef3f070894c09afda
Reviewed-on: https://go-review.googlesource.com/25586
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-08-09 15:48:26 +00:00
Cherry Zhang
0484052358 [dev.ssa] cmd/compile: remove flags from regMask
Reg allocator skips flag-typed values. Flag allocator uses the type
and whether the op has "clobberFlags" set.

Tested on AMD64, ARM, ARM64, 386. Passed 'toolstash -cmp' on AMD64.
PPC64 is coded blindly.

Change-Id: Ib1cc27efecef6a1bb27f7d7ed035a582660d244f
Reviewed-on: https://go-review.googlesource.com/25480
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-08-07 03:08:03 +00:00
David Chase
dd1d9b36c6 [dev.ssa] cmd/compile: PPC64, add cmp->bool, some shifts, hmul
Includes hmul (all widths)
compare for boolean result and simplifications
shift operations plus changes/additions for implementation
(ORN, ADDME, ADDC)

Also fixed a backwards-operand CMP.

Change-Id: Id723c4e25125c38e0d9ab9ec9448176b75f4cdb4
Reviewed-on: https://go-review.googlesource.com/25410
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-08-04 18:17:52 +00:00
David Chase
dede2061f3 [dev.ssa] cmd/compile: PPC64, add more zeroing and moves
Passes light testing.
Modified to avoid possible exposure of "exterior" pointers
to GC.

Updates #16010.

Change-Id: I41fced4fa83cefb9542dff8c8dee1a0c48056b3c
Reviewed-on: https://go-review.googlesource.com/25310
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-01 18:26:03 +00:00
David Chase
2d16e43158 [dev.ssa] cmd/compile: PPC64, basic support for all calls and "miscellaneous"
Added support for ClosureCall, DeferCall, InterCall
(GoCall not yet tested).

Added support for GetClosurePtr, IsNonNil, IsInBounds, IsSliceInBounds, NilCheck
(Convert and GetG not yet tested)

Still need to implement NilCheck optimizations.
Fixed move boolean constant, order of operands to subtract.

Updates #16010.

Change-Id: Ibe0f6a6e688df4396cd77de0e9095997e4ca8ed2
Reviewed-on: https://go-review.googlesource.com/25241
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-07-26 20:59:26 +00:00
Cherry Zhang
ae9570a5b9 [dev.ssa] cmd/compile: initial ARM64 SSA port
Mostly copied from ARM port, with instruction names and Prog fields
adjusted, and 64-bit int ops added. Not complete.

Fib compiles and runs correctly.

Change-Id: Id3ecb0d4b571200a035344b3e8e4408769f76221
Reviewed-on: https://go-review.googlesource.com/25130
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-07-23 21:25:58 +00:00
Cherry Zhang
6b6de15d32 [dev.ssa] cmd/compile: support NaCl in SSA for ARM
NaCl code runs in sandbox and there are restrictions for its
instruction uses
(https://developer.chrome.com/native-client/reference/sandbox_internals/arm-32-bit-sandbox).

Like the legacy backend, on NaCl,
- don't use R9, which is used as NaCl's "thread pointer".
- don't use Duff's device.
- don't use indexed load/stores.
- the assembler rewrites DIV/MOD to runtime calls, which on NaCl
  clobbers R12, so R12 is marked as clobbered for DIV/MOD.
- other restrictions are satisfied by the assembler.

Enable SSA specific tests on nacl/arm, and disable non-SSA ones.

Updates #15365.

Change-Id: I9262693ec6756b89ca29d3ae4e52a96fe5403b02
Reviewed-on: https://go-review.googlesource.com/24859
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-07-16 03:13:45 +00:00
Keith Randall
14cf6e2083 [dev.ssa] cmd/compile: initial 386 SSA port
Basically just copied all the amd64 files, removed all the *Q ops,
and rebuilt.

Compiles fib successfully.

Still need to do:
 - all the 64->32 bit op translations.
 - audit for instructions that aren't available on 386.
 - GO386=387?

Update #16358

Change-Id: Ib8c684586416a554a527a5eefa0cff71424e36f5
Reviewed-on: https://go-review.googlesource.com/24912
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-07-13 23:43:50 +00:00
Lynn Boger
03d152f36f [dev.ssa] cmd/compile: Add initial SSA configuration for PPC64
This adds the initial SSA implementation for PPC64.
Builds golang and all.bash runs correctly.  Simple hello.go
builds but does not run.

Change-Id: I7cec211b934cd7a2dd75a6cdfaf9f71867063466
Reviewed-on: https://go-review.googlesource.com/24453
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-28 15:41:20 +00:00
Cherry Zhang
93b8aab5c9 [dev.ssa] cmd/compile: handle GetG on ARM
Use hardware g register (R10) for GetG, allow g to appear at LHS of
some ops.

Progress on SSA backend for ARM. Now everything compiles and runs.

Updates #15365.

Change-Id: Icdf93585579faa86cc29b1e17ab7c90f0119fc4e
Reviewed-on: https://go-review.googlesource.com/23952
Reviewed-by: David Chase <drchase@google.com>
2016-06-15 15:36:35 +00:00
Cherry Zhang
90883091ff [dev.ssa] cmd/compile: clean up hardcoded regmasks in ssa/regalloc.go
Auto-generate register masks and load them through Config.

Passed toolstash -cmp on AMD64.

Tests phi_ssa.go and regalloc_ssa.go in cmd/compile/internal/gc/testdata
passed on ARM.

Updates #15365.

Change-Id: I393924d68067f2dbb13dab82e569fb452c986593
Reviewed-on: https://go-review.googlesource.com/23292
Reviewed-by: David Chase <drchase@google.com>
2016-06-02 13:01:44 +00:00
Cherry Zhang
8756d9253f [dev.ssa] cmd/compile: decompose 64-bit integer on ARM
Introduce dec64 rules to (generically) decompose 64-bit integer on
32-bit architectures. 64-bit integer is composed/decomposed with
Int64Make/Hi/Lo ops, as for complex types.

The idea of dealing with Add64 is the following:

(Add64 (Int64Make xh xl) (Int64Make yh yl))
->
(Int64Make
	(Add32withcarry xh yh (Select0 (Add32carry xl yl)))
	(Select1 (Add32carry xl yl)))

where Add32carry returns a tuple (flags,uint32). Select0 and Select1
read the first and the second component of the tuple, respectively.
The two Add32carry will be CSE'd.

Similarly for multiplication, Mul32uhilo returns a tuple (hi, lo).

Also add support of KeepAlive, to fix build after merge.

Tests addressed_ssa.go, array_ssa.go, break_ssa.go, chan_ssa.go,
cmp_ssa.go, ctl_ssa.go, map_ssa.go, and string_ssa.go in
cmd/compile/internal/gc/testdata passed.

Progress on SSA for ARM. Still not complete.

Updates #15365.

Change-Id: I7867c76785a456312de5d8398a6b3f7ca5a4f7ec
Reviewed-on: https://go-review.googlesource.com/23213
Reviewed-by: Keith Randall <khr@golang.org>
2016-06-02 13:01:09 +00:00
David Chase
31e13c83c2 [dev.ssa] Merge branch 'master' into dev.ssa
Change-Id: Iabc80b6e0734efbd234d998271e110d2eaad41dd
2016-05-27 15:19:33 -04:00
Cherry Zhang
ccaed50c7b [dev.ssa] cmd/compile: handle boolean values for SSA on ARM
Fix hardcoded flag register mask in ssa/flagalloc.go by auto-generating
the mask.

Also fix a mistake (in previous CL) about conditional branches.

Progress on SSA backend for ARM. Still not complete. Now "container/ring"
package compiles and tests passed.

Updates #15365.

Change-Id: Id7c8805c30dbb8107baedb485ed0f71f59ed6ea8
Reviewed-on: https://go-review.googlesource.com/23093
Reviewed-by: Keith Randall <khr@golang.org>
2016-05-19 02:48:36 +00:00
David Chase
6b99fb5bea cmd/compile: use sparse algorithm for phis in large program
This adds a sparse method for locating nearest ancestors
in a dominator tree, and checks blocks with more than one
predecessor for differences and inserts phi functions where
there are.

Uses reversed post order to cut number of passes, running
it from first def to last use ("last use" for paramout and
mem is end-of-program; last use for a phi input from a
backedge is the source of the back edge)

Includes a cutover from old algorithm to new to avoid paying
large constant factor for small programs.  This keeps normal
builds running at about the same time, while not running
over-long on large machine-generated inputs.

Add "phase" flags for ssa/build -- ssa/build/stats prints
number of blocks, values (before and after linking references
and inserting phis, so expansion can be measured), and their
product; the product governs the cutover, where a good value
seems to be somewhere between 1 and 5 million.

Among the files compiled by make.bash, this is the shape of
the tail of the distribution for #blocks, #vars, and their
product:

	 #blocks	#vars	    product
 max	6171	28180	173,898,780
99.9%	1641	 6548	 10,401,878
  99%	 463	 1909	    873,721
  95%	 152	  639	     95,235
  90%	  84	  359	     30,021

The old algorithm is indeed usually fastest, for 99%ile
values of usually.

The fix to LookupVarOutgoing
( https://go-review.googlesource.com/#/c/22790/ )
deals with some of the same problems addressed by this CL,
but on at least one bug ( #15537 ) this change is still
a significant help.

With this CL:
/tmp/gopath$ rm -rf pkg bin
/tmp/gopath$ time go get -v -gcflags -memprofile=y.mprof \
   github.com/gogo/protobuf/test/theproto3/combos/...
...
real	4m35.200s
user	13m16.644s
sys	0m36.712s
and pprof reports 3.4GB allocated in one of the larger profiles

With tip:
/tmp/gopath$ rm -rf pkg bin
/tmp/gopath$ time go get -v -gcflags -memprofile=y.mprof \
   github.com/gogo/protobuf/test/theproto3/combos/...
...
real	10m36.569s
user	25m52.286s
sys	4m3.696s
and pprof reports 8.3GB allocated in the same larger profile

With this CL, most of the compilation time on the benchmarked
input is spent in register/stack allocation (cumulative 53%)
and in the sparse lookup algorithm itself (cumulative 20%).

Fixes #15537.

Change-Id: Ia0299dda6a291534d8b08e5f9883216ded677a00
Reviewed-on: https://go-review.googlesource.com/22342
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-16 21:08:05 +00:00
Keith Randall
b64c7fc683 cmd/compile: never CSE two memories
It never makes sense to CSE two ops that generate memory.
We might as well start those ops off in their own partition.

Fixes #15520

Change-Id: I0091ed51640f2c10cd0117f290b034dde7a86721
Reviewed-on: https://go-review.googlesource.com/22741
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-03 22:45:53 +00:00
Josh Bleecher Snyder
db5338f879 cmd/compile: teach CSE that new objects are bespoke
runtime.newobject never returns the same thing twice,
so the resulting value will never be a common subexpression.

This helps when compiling large static data structures
that include pointers, such as maps and slices.
No clear performance impact on other code. (See below.)

For the code in issue #15112:

Before:
  real	1m14.238s
  user	1m18.985s
  sys	0m0.787s

After:
  real	0m47.172s
  user	0m52.248s
  sys	0m0.767s

For the code in issue #15235, size 10k:

Before:
  real	0m44.916s
  user	0m46.577s
  sys	0m0.304s

After:
  real	0m7.703s
  user	0m9.041s
  sys	0m0.316s

Still more work to be done, particularly for #15112.

Updates #15112
Updates #15235


name       old time/op      new time/op      delta
Template        330ms ±11%       333ms ±13%    ~           (p=0.749 n=20+19)
Unicode         148ms ± 6%       152ms ± 8%    ~           (p=0.072 n=18+20)
GoTypes         1.01s ± 7%       1.01s ± 3%    ~           (p=0.583 n=20+20)
Compiler        5.04s ± 2%       5.06s ± 2%    ~           (p=0.314 n=20+20)

name       old user-ns/op   new user-ns/op   delta
Template   444user-ms ±11%  445user-ms ±10%    ~           (p=0.738 n=20+20)
Unicode    215user-ms ± 5%  218user-ms ± 5%    ~           (p=0.239 n=18+18)
GoTypes    1.45user-s ± 3%  1.45user-s ± 4%    ~           (p=0.620 n=20+20)
Compiler   7.23user-s ± 2%  7.22user-s ± 2%    ~           (p=0.901 n=20+19)

name       old alloc/op     new alloc/op     delta
Template       55.0MB ± 0%      55.0MB ± 0%    ~           (p=0.547 n=20+20)
Unicode        37.6MB ± 0%      37.6MB ± 0%    ~           (p=0.301 n=20+20)
GoTypes         177MB ± 0%       177MB ± 0%    ~           (p=0.065 n=20+19)
Compiler        798MB ± 0%       797MB ± 0%  -0.05%        (p=0.000 n=19+20)

name       old allocs/op    new allocs/op    delta
Template         492k ± 0%        493k ± 0%  +0.03%        (p=0.030 n=20+20)
Unicode          377k ± 0%        377k ± 0%    ~           (p=0.423 n=20+19)
GoTypes         1.40M ± 0%       1.40M ± 0%    ~           (p=0.102 n=20+20)
Compiler        5.53M ± 0%       5.53M ± 0%    ~           (p=0.094 n=17+18)

name       old text-bytes   new text-bytes   delta
HelloSize        561k ± 0%        561k ± 0%    ~     (all samples are equal)
CmdGoSize       6.13M ± 0%       6.13M ± 0%    ~     (all samples are equal)

name       old data-bytes   new data-bytes   delta
HelloSize        128k ± 0%        128k ± 0%    ~     (all samples are equal)
CmdGoSize        306k ± 0%        306k ± 0%    ~     (all samples are equal)

name       old exe-bytes    new exe-bytes    delta
HelloSize        905k ± 0%        905k ± 0%    ~     (all samples are equal)
CmdGoSize       9.64M ± 0%       9.64M ± 0%    ~     (all samples are equal)

Change-Id: Id774e2901d7701a3ec7a1c1d1cf1d9327a4107fc
Reviewed-on: https://go-review.googlesource.com/21937
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Todd Neal <todd@tneal.org>
2016-04-13 02:11:56 +00:00
Keith Randall
b04e145248 cmd/compile: fix naming of decomposed structs
When a struct is SSAable, we will name its component parts
by their field names.  For example,
type T struct {
     a, b, c int
}
If we ever need to spill a variable x of type T, we will
spill its individual components to variables named x.a, x.b,
and x.c.

Change-Id: I857286ff1f2597f2c4bbd7b4c0b936386fb37131
Reviewed-on: https://go-review.googlesource.com/21389
Reviewed-by: David Chase <drchase@google.com>
2016-04-11 17:11:23 +00:00
Keith Randall
4a7aba775d cmd/compile: better job of naming compound types
Compound AUTO types weren't named previously.  That was because live
variable analysis (plive.go) doesn't handle spilling to compound types.
It can't handle them because there is no valid place to put VARDEFs when
regalloc is spilling compound types.

compound types = multiword builtin types: complex, string, slice, and
interface.

Instead, we split named AUTOs into individual one-word variables.  For
example, a string s gets split into a byte ptr s.ptr and an integer
s.len.  Those two variables can be spilled to / restored from
independently.  As a result, live variable analysis can handle them
because they are one-word objects.

This CL will change how AUTOs are described in DWARF information.
Consider the code:

func f(s string, i int) int {
    x := s[i:i+5]
    g()
    return lookup(x)
}

The old compiler would spill x to two consecutive slots on the stack,
both named x (at offsets 0 and 8).  The new compiler spills the pointer
of x to a slot named x.ptr.  It doesn't spill x.len at all, as it is a
constant (5) and can be rematerialized for the call to lookup.

So compound objects may not be spilled in their entirety, and even if
they are they won't necessarily be contiguous.  Such is the price of
optimization.

Re-enable live variable analysis tests.  One test remains disabled, it
fails because of #14904.

Change-Id: I8ef2b5ab91e43a0d2136bfc231c05d100ec0b801
Reviewed-on: https://go-review.googlesource.com/21233
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-03-31 22:18:26 +00:00
Dave Cheney
b9feb91f32 cmd/compile: minor cleanups
Some minor scoping cleanups found by a very old version of grind.

Change-Id: I1d373817586445fc87e38305929097b652696fdd
Reviewed-on: https://go-review.googlesource.com/21064
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-24 11:18:04 +00:00
Brad Fitzpatrick
ca5417b8e0 cmd/compile: reduce some SSA garbage
It's pretty hard to get reliable CPU numbers, even with 50 runs on an
otherwise-idle physical Linux machine, but the garbage reduction
numbers are nice. To get useful time/op numbers, I modified
compilebench to report user CPU time instead of wall time:

name       old time/op     new time/op     delta
Template       547ms ± 6%      557ms ± 5%   +1.80%        (p=0.001 n=49+49)
Unicode        360ms ± 9%      365ms ± 6%     ~           (p=0.094 n=50+45)
GoTypes        1.84s ± 3%      1.82s ± 3%   -1.50%        (p=0.000 n=50+49)
Compiler       9.19s ± 2%      9.02s ± 2%   -1.87%        (p=0.000 n=45+50)

name       old alloc/op    new alloc/op    delta
Template      63.3MB ± 0%     59.1MB ± 0%   -6.72%        (p=0.000 n=50+50)
Unicode       43.1MB ± 0%     42.9MB ± 0%   -0.47%        (p=0.000 n=50+49)
GoTypes        220MB ± 0%      200MB ± 0%   -9.00%        (p=0.000 n=50+50)
Compiler      1.00GB ± 0%     0.89GB ± 0%  -10.09%        (p=0.000 n=50+49)

name       old allocs/op   new allocs/op   delta
Template        681k ± 0%       680k ± 0%   -0.16%        (p=0.000 n=50+48)
Unicode         541k ± 0%       541k ± 0%   -0.02%        (p=0.011 n=48+50)
GoTypes        2.08M ± 0%      2.08M ± 0%   -0.19%        (p=0.000 n=48+50)
Compiler       9.24M ± 0%      9.23M ± 0%   -0.11%        (p=0.000 n=50+50)

Change-Id: I1fac4ebf85a1783e3289c3ffb1ed365442837643
Reviewed-on: https://go-review.googlesource.com/20995
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Keith Randall <khr@golang.org>
2016-03-23 19:50:02 +00:00
Keith Randall
4c9a470d46 cmd/compile: start on ARM port
Start working on arm port.  Gets close to correct
code for fibonacci:
    func fib(n int) int {
        if n < 2 {
            return n
        }
        return fib(n-1) + fib(n-2)
    }

Still a lot to do, but this is a good starting point.

Cleaned up some arch-specific dependencies in regalloc.

Change-Id: I4301c6c31a8402168e50dcfee8bcf7aee73ea9d5
Reviewed-on: https://go-review.googlesource.com/21000
Reviewed-by: David Chase <drchase@google.com>
2016-03-23 17:46:05 +00:00
Todd Neal
98b88de56f cmd/compile: change the type of ssa Warnl line number
Line numbers are always int32, so the Warnl function should take the
line number as an int32 as well.  This matches gc.Warnl and removes
a cast every place it's used.

Change-Id: I5d6201e640d52ec390eb7174f8fd8c438d4efe58
Reviewed-on: https://go-review.googlesource.com/20662
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-03-14 11:04:40 +00:00
David du Colombier
d55a099e22 cmd/compile: don't use duffcopy and duffzero on Plan 9
The ssa compiler uses the duffcopy and duffzero functions,
which rely on the MOVUPS instructions.

However, this doesn't work on Plan 9, since floating point
operations are not allowed in the note handler.

This change disables the use of duffcopy and duffzero
on Plan 9 in the ssa compiler.

Updates #14605.

Change-Id: I017f8ff83de00eabaf7e146b4344a863db1dfddc
Reviewed-on: https://go-review.googlesource.com/20171
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-03 21:36:11 +00:00
Brad Fitzpatrick
5fea2ccc77 all: single space after period.
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 00:13:47 +00:00
David Chase
378a863682 [dev.ssa] cmd/compile: enhance command line option processing for SSA
The -d compiler flag can also specify ssa phase and flag,
for example -d=ssa/generic_cse/time,ssa/generic_cse/stats

Spaces in the phase names can be specified with an
underscore.  Flags currently parsed (not necessarily
recognized by the phases yet) are:

   on, off, mem, time, debug, stats, and test

On, off and time are handled in the harness,
debug, stats, and test are interpreted by the phase itself.

The pass is now attached to the Func being compiled, and a
new method logStats(key, ...value) on *Func to encourage a
semi-standardized format for that output.  Output fields
are separated by tabs to ease digestion by awk and
spreadsheets.  For example,
	if f.pass.stats > 0 {
		f.logStat("CSE REWRITES", rewrites)
	}

Change-Id: I16db2b5af64c50ca9a47efeb51d961147a903abc
Reviewed-on: https://go-review.googlesource.com/19885
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Todd Neal <todd@tneal.org>
2016-02-25 20:32:15 +00:00
David Chase
b86cafc7dc [dev.ssa] cmd/compile: memory allocation tweaks to regalloc and dom
Spotted a minor source of excess allocation in the register
allocator.  Rearranged the dominator tree code to pull its
scratch memory from a reused buffer attached to Config.

Change-Id: I6da6e7b112f7d3eb1fd00c58faa8214cdea44e38
Reviewed-on: https://go-review.googlesource.com/19450
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-22 15:32:58 +00:00
Todd Neal
3297a4f5f3 [dev.ssa] cmd/compile: cache sparse sets in Config
Move the cached sparse sets to the Config.  I tested make.bash with
pre-allocating sets of size 150 and not caching very small sets, but the
difference between this implementation (no min size, no preallocation)
and a min size with preallocation was fairly negligible:

Number of sparse sets allocated:
Cached in Config w/none preallocated no min size    3684 *this CL*
Cached in Config w/three preallocated no min size   3370
Cached in Config w/three preallocated min size=150  3370
Cached in Config w/none preallocated min size=150  15947
Cached in Func,  w/no min                          96996 *previous code*

Change-Id: I7f9de8a7cae192648a7413bfb18a6690fad34375
Reviewed-on: https://go-review.googlesource.com/19152
Reviewed-by: Keith Randall <khr@golang.org>
2016-02-02 18:08:46 +00:00
David Chase
88b230eaa6 [dev.ssa] cmd/compile: exposed do-log boolean to reduce allocations
From memory profiling, about 3% reduction in allocation count.

Change-Id: I4b662d55b8a94fe724759a2b22f05a08d0bf40f8
Reviewed-on: https://go-review.googlesource.com/19103
Reviewed-by: Keith Randall <khr@golang.org>
2016-01-29 21:30:29 +00:00
Keith Randall
2f57d0fe02 [dev.ssa] cmd/compile: preallocate small-numbered values and blocks
Speeds up the compiler ~5%.

Change-Id: Ia5cf0bcd58701fd14018ec77d01f03d5c7d6385b
Reviewed-on: https://go-review.googlesource.com/19060
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-01-28 22:52:42 +00:00
Keith Randall
6a96a2fe5a [dev.ssa] cmd/compile: make cse faster
It is one of the slowest compiler phases right now, and we
run two of them.

Instead of using a map to make the initial partition, use a sort.
It is much less memory intensive.

Do a few optimizations to avoid work for size-1 equivalence classes.

Implement -N.

Change-Id: I1d2d85d3771abc918db4dd7cc30b0b2d854b15e1
Reviewed-on: https://go-review.googlesource.com/19024
Reviewed-by: David Chase <drchase@google.com>
2016-01-28 20:59:20 +00:00
Keith Randall
b5c5efd5de [dev.ssa] cmd/compile: optimize phi ops
Redo how we keep track of forward references when building SSA.
When the forward reference is resolved, update the Value node
in place.

Improve the phi elimination pass so it can simplify phis of phis.

Give SSA package access to decoded line numbers.  Fix line numbers
for constant booleans.

Change-Id: I3dc9896148d260be2f3dd14cbe5db639ec9fa6b7
Reviewed-on: https://go-review.googlesource.com/18674
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
2016-01-20 21:45:37 +00:00
Keith Randall
da8af47710 [dev.ssa] cmd/compile: report better line numbers for Unimplemented/Fatal
If a failure occurs in SSA processing, we always report the
last line of the function we're compiling.  Modify the callbacks
from SSA to the GC compiler so we can pass a line number back
and use it in Fatalf.

Change-Id: Ifbfad50d5e167e997e0a96f0775bcc369f5c397e
Reviewed-on: https://go-review.googlesource.com/18599
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-01-19 15:43:32 +00:00
Keith Randall
02f4d0a130 [dev.ssa] cmd/compile: start arguments as spilled
Declare a function's arguments as having already been
spilled so their use just requires a restore.

Allow spill locations to be portions of larger objects the stack.
Required to load portions of compound input arguments.

Rename the memory input to InputMem.  Use Arg for the
pre-spilled argument values.

Change-Id: I8fe2a03ffbba1022d98bfae2052b376b96d32dda
Reviewed-on: https://go-review.googlesource.com/16536
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2015-11-03 17:29:40 +00:00
David Chase
729abfa35c [dev.ssa] cmd/compile: default compile+test with SSA
Some tests disabled, some bifurcated into _ssa and not,
with appropriate logging added to compiler.

"tests/live.go" in particular needs attention.

SSA-specific testing removed, since it's all SSA now.

Added "-run_skips" option to tests/run.go to simplify
checking whether a test still fails (or how it fails)
on a skipped platform.

The compiler now compiles with SSA by default.
If you don't want SSA, specify GOSSAHASH=n (or N) as
an environment variable.  Function names ending in "_ssa"
are always SSA-compiled.

GOSSAFUNC=fname retains its "SSA for fname, log to ssa.html"
GOSSAPKG=pkg only has an effect when GOSSAHASH=n
GOSSAHASH=10101 etc retains its name-hash-matching behavior
for purposes of debugging.

See #13068

Change-Id: I8217bfeb34173533eaeb391b5f6935483c7d6b43
Reviewed-on: https://go-review.googlesource.com/16299
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
2015-10-30 20:35:20 +00:00
Keith Randall
c24681ae2e [dev.ssa] cmd/compile: remember names of values
For debugging, spill values to named variables instead of autotmp_
variables if possible.  We do this by keeping a name -> value map
for each function, keep it up-to-date during deadcode elim, and use
it to override spill decisions in stackalloc.

It might even make stack frames a bit smaller, as it makes it easy
to identify a set of spills which are likely not to interfere.

This just works for one-word variables for now.  Strings/slices
will be a separate CL.

Change-Id: Ie89eba8cab16bcd41b311c479ec46dd7e64cdb67
Reviewed-on: https://go-review.googlesource.com/16336
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2015-10-28 17:00:31 +00:00
Keith Randall
7d61246972 [dev.ssa] cmd/compile: implement reserved registers
BP for framepointer experiment
R15 for dynamic linking

Change-Id: I28e48be461d04a4d5c9b013f48fce5c0e58d6a08
Reviewed-on: https://go-review.googlesource.com/16231
Run-TryBot: Todd Neal <todd@tneal.org>
Reviewed-by: Todd Neal <todd@tneal.org>
2015-10-23 04:14:06 +00:00
Keith Randall
37590bddc4 [dev.ssa] cmd/compile: move un-SSAable objects
We need to move any objects whose types are not SSA-able.

Fixes the "not lowered: Load ARRAY PTR64 mem" errors.

Change-Id: I7a0b609f917d7fb34bc9215fee4da15f9961cf6c
Reviewed-on: https://go-review.googlesource.com/14753
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-09-19 18:22:46 +00:00