CL 622236 forgot to check the mask was also a 32 bit rotate mask. Add
a modified version of isPPC64WordRotateMask which valids the mask is
contiguous and fits inside a uint32.
I don't this is possible when merging SRDconst, the first check should
always reject such combines. But, be extra careful and do it there
too.
Fixes#73153
Change-Id: Ie95f74ec5e7d89dc761511126db814f886a7a435
Reviewed-on: https://go-review.googlesource.com/c/go/+/679775
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Jayanth Krishnamurthy <jayanth.krishnamurthy@ibm.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
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Reviewed-by: Keith Randall <khr@golang.org>
unique.Make always copies strings passed into it, so it's safe to not
copy byte slices converted to strings either. Handle this just like map
accesses with string(b) as keys.
This CL only handles unique.Make(string(b)), not nested cases like
unique.Make([2]string{string(b1), string(b2)}); this could be done in a
followup CL but the map lookup code in walk is sufficiently different
than the call handling code that I didn't attempt it. (SSA is much
easier).
Fixes#71926
Change-Id: Ic2f82f2f91963d563b4ddb1282bd49fc40da8b85
Reviewed-on: https://go-review.googlesource.com/c/go/+/672135
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
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Today, this interface conversion causes the struct literal
to be heap allocated:
var sink any
func example1() {
sink = S{1, 1}
}
For basic literals like integers that are directly used in
an interface conversion that would otherwise allocate, the compiler
is able to use read-only global storage (see #18704).
This CL extends that to struct and array literals as well by creating
read-only global storage that is able to represent for example S{1, 1},
and then using a pointer to that storage in the interface
when the interface conversion happens.
A more challenging example is:
func example2() {
v := S{1, 1}
sink = v
}
In this case, the struct literal is not directly part of the
interface conversion, but is instead assigned to a local variable.
To still avoid heap allocation in cases like this, in walk we
construct a cache that maps from expressions used in interface
conversions to earlier expressions that can be used to represent the
same value (via ir.ReassignOracle.StaticValue). This is somewhat
analogous to how we avoided heap allocation for basic literals in
CL 649077 earlier in our stack, though here we also need to do a
little more work to create the read-only global.
CL 649076 (also earlier in our stack) added most of the tests
along with debug diagnostics in convert.go to make it easier
to test this change.
See the writeup in #71359 for details.
Fixes#71359Fixes#71323
Updates #62653
Updates #53465
Updates #8618
Change-Id: I8924f0c69ff738ea33439bd6af7b4066af493b90
Reviewed-on: https://go-review.googlesource.com/c/go/+/649555
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Reviewed-by: Keith Randall <khr@google.com>
In the loong64 instruction set, there is no NORI instruction,
so the immediate value in NORconst need to be stored in register
and then use the three-register NOR instruction.
Change-Id: I5ef697450619317218cb3ef47fc07e238bdc2139
Reviewed-on: https://go-review.googlesource.com/c/go/+/673836
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
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This CL implements the TODO in combineStores to allow combining
stores of different sizes, as long as the total size aligns to
2, 4, 8.
Fixes#72832.
Change-Id: I6d1d471335da90d851ad8f3b5a0cf10bdcfa17c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/661855
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
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-N+1 <= x % N <= N-1
This is useful for cases like:
func setBit(b []byte, i int) {
b[i/8] |= 1<<(i%8)
}
The shift does not need protection against larger-than-7 cases.
(It does still need protection against <0 cases.)
Change-Id: Idf83101386af538548bfeb6e2928cea855610ce2
Reviewed-on: https://go-review.googlesource.com/c/go/+/672995
Reviewed-by: Jorropo <jorropo.pgm@gmail.com>
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x += *p
We want to do this with a single load+add operation on amd64.
The tricky part is that we don't want to combine if there are
other uses of x after this instruction.
Implement a simple detector that seems to capture a common situation -
x += *p is in a loop, and the other use of x is after loop exit.
In that case, it does not hurt to do the load+add combo.
Change-Id: I466174cce212e78bde83f908cc1f2752b560c49c
Reviewed-on: https://go-review.googlesource.com/c/go/+/672957
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: David Chase <drchase@google.com>
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for ..; ..; i++ {
...
}
We want to schedule the i++ late in the block, so that all other
uses of i in the block are scheduled first. That way, i++ can
happen in place in a register instead of requiring a temporary register.
Change-Id: Id777407c7e67a5ddbd8e58251099b0488138c0df
Reviewed-on: https://go-review.googlesource.com/c/go/+/672998
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Use an automatic algorithm to generate strength reduction code.
You give it all the linear combination (a*x+b*y) instructions in your
architecture, it figures out the rest.
Just amd64 and arm64 for now.
Fixes#67575
Change-Id: I35c69382bebb1d2abf4bb4e7c43fd8548c6c59a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/626998
Reviewed-by: Jakub Ciolek <jakub@ciolek.dev>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@google.com>
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For riscv64/rva22u64 and above, we can intrinsify math/bits.OnesCount
using the CPOP/CPOPW machine instructions. Since the native Go
implementation of OnesCount is relatively expensive, it is also
worth emitting a check for Zbb support when compiled for rva20u64.
On a Banana Pi F3, with GORISCV64=rva22u64:
│ oc.1 │ oc.2 │
│ sec/op │ sec/op vs base │
OnesCount-8 16.930n ± 0% 4.389n ± 0% -74.08% (p=0.000 n=10)
OnesCount8-8 5.642n ± 0% 5.016n ± 0% -11.10% (p=0.000 n=10)
OnesCount16-8 9.404n ± 0% 5.015n ± 0% -46.67% (p=0.000 n=10)
OnesCount32-8 13.165n ± 0% 4.388n ± 0% -66.67% (p=0.000 n=10)
OnesCount64-8 16.300n ± 0% 4.388n ± 0% -73.08% (p=0.000 n=10)
geomean 11.40n 4.629n -59.40%
On a Banana Pi F3, compiled with GORISCV64=rva20u64 and with Zbb
detection enabled:
│ oc.3 │ oc.4 │
│ sec/op │ sec/op vs base │
OnesCount-8 16.930n ± 0% 5.643n ± 0% -66.67% (p=0.000 n=10)
OnesCount8-8 5.642n ± 0% 5.642n ± 0% ~ (p=0.447 n=10)
OnesCount16-8 10.030n ± 0% 6.896n ± 0% -31.25% (p=0.000 n=10)
OnesCount32-8 13.170n ± 0% 5.642n ± 0% -57.16% (p=0.000 n=10)
OnesCount64-8 16.300n ± 0% 5.642n ± 0% -65.39% (p=0.000 n=10)
geomean 11.55n 5.873n -49.16%
On a Banana Pi F3, compiled with GORISCV64=rva20u64 but with Zbb
detection disabled:
│ oc.3 │ oc.5 │
│ sec/op │ sec/op vs base │
OnesCount-8 16.93n ± 0% 29.47n ± 0% +74.07% (p=0.000 n=10)
OnesCount8-8 5.642n ± 0% 5.643n ± 0% ~ (p=0.191 n=10)
OnesCount16-8 10.03n ± 0% 15.05n ± 0% +50.05% (p=0.000 n=10)
OnesCount32-8 13.17n ± 0% 18.18n ± 0% +38.04% (p=0.000 n=10)
OnesCount64-8 16.30n ± 0% 21.94n ± 0% +34.60% (p=0.000 n=10)
geomean 11.55n 15.84n +37.16%
For hardware without Zbb, this adds ~5ns overhead, while for hardware
with Zbb we achieve a performance gain up of up to 11ns. It is worth
noting that OnesCount8 is cheap enough that it is preferable to stick
with the generic version in this case.
Change-Id: Id657e40e0dd1b1ab8cc0fe0f8a68df4c9f2d7da5
Reviewed-on: https://go-review.googlesource.com/c/go/+/660856
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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The full 64x64->128 multiply comes up when using bits.Mul64.
The 64x64->64+overflow multiply comes up in unsafe.Slice when using
a constant length.
Change-Id: I298515162ca07d804b2d699d03bc957ca30a4ebc
Reviewed-on: https://go-review.googlesource.com/c/go/+/667175
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Keith Randall <khr@google.com>
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If the thing we're ranging over is an array or ptr to array, and
it doesn't have a function call or channel receive in it, then we
shouldn't evaluate it.
Typecheck the ranged-over value as a constant in that case.
That makes the unified exporter replace the range expression
with a constant int.
Change-Id: I0d4ea081de70d20cf6d1fa8d25ef6cb021975554
Reviewed-on: https://go-review.googlesource.com/c/go/+/659317
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Reviewed-by: Robert Griesemer <gri@google.com>
Improve the compiler's store-to-load forwarding optimization by relaxing the
type comparison condition. Instead of requiring exact type equality (CMPeq),
we now use copyCompatibleType which allows forwarding between compatible
types where safe.
Fix several size comparison bugs in the nested store patterns. Previously,
we were comparing the size of the outer store with the load type,
rather than comparing with the size of the actual store being forwarded
from.
Skip OpConvert in dead store elimination to help get rid of dead stores such
as zeroing slices. OpConvert, like OpInlMark, doesn't really use the memory.
This optimization is particularly beneficial for code that creates slices with
computed pointers, such as the runtime's heapBitsSlice function, where
intermediate calculations were previously causing the compiler to miss
store-to-load forwarding opportunities.
Local sweet run result on an x86_64 laptop:
│ Orig.res │ Hopt.res │
│ sec/op │ sec/op vs base │
BiogoIgor-8 5.303 ± 1% 5.322 ± 1% ~ (p=0.190 n=10)
BiogoKrishna-8 7.894 ± 1% 7.828 ± 2% ~ (p=0.190 n=10)
BleveIndexBatch100-8 2.257 ± 1% 2.248 ± 2% ~ (p=0.529 n=10)
EtcdPut-8 30.12m ± 1% 30.03m ± 1% ~ (p=0.796 n=10)
EtcdSTM-8 127.1m ± 1% 126.2m ± 0% -0.74% (p=0.023 n=10)
GoBuildKubelet-8 52.21 ± 0% 52.05 ± 1% ~ (p=0.063 n=10)
GoBuildKubeletLink-8 4.342 ± 1% 4.305 ± 0% -0.85% (p=0.000 n=10)
GoBuildIstioctl-8 43.33 ± 0% 43.24 ± 0% -0.22% (p=0.015 n=10)
GoBuildIstioctlLink-8 4.604 ± 1% 4.598 ± 0% ~ (p=0.063 n=10)
GoBuildFrontend-8 15.33 ± 0% 15.29 ± 0% ~ (p=0.143 n=10)
GoBuildFrontendLink-8 740.0m ± 1% 737.7m ± 1% ~ (p=0.912 n=10)
GopherLuaKNucleotide-8 9.590 ± 1% 9.656 ± 1% ~ (p=0.165 n=10)
MarkdownRenderXHTML-8 96.97m ± 1% 97.26m ± 2% ~ (p=0.105 n=10)
Tile38QueryLoad-8 335.9µ ± 1% 335.6µ ± 1% ~ (p=0.481 n=10)
geomean 1.336 1.333 -0.22%
Change-Id: I031552623e6d5a3b1b5be8325e6314706e45534f
Reviewed-on: https://go-review.googlesource.com/c/go/+/662075
Reviewed-by: Carlos Amedee <carlos@golang.org>
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Auto-Submit: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Optimise more branches with zero on riscv64. In particular, BLTU with
zero occurs with IsInBounds checks for index zero. This currently results
in two instructions and requires an additional register:
li t2, 0
bltu t2, t1, 0x174b4
This is equivalent to checking if the bounds is not equal to zero. With
this change:
bnez t1, 0x174c0
This removes more than 500 instructions from the Go binary on riscv64.
Change-Id: I6cd861d853e3ef270bd46dacecdfaa205b1c4644
Reviewed-on: https://go-review.googlesource.com/c/go/+/606715
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
All other files here use the codegen package.
Change-Id: I714162941b9fa9051dacc29643e905fe60b9304b
Reviewed-on: https://go-review.googlesource.com/c/go/+/661135
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Reviewed-by: Keith Randall <khr@golang.org>
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This adds tests for type conversion and shifts, detailing various
poor bad code generation that currently exists for riscv64. This
will be addressed in future CLs.
Change-Id: Ie1d366dfe878832df691600f8500ef383da92848
Reviewed-on: https://go-review.googlesource.com/c/go/+/615678
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>
Reviewed-by: Mark Ryan <markdryan@rivosinc.com>
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Use NEGW to produce a negated and sign extended word, rather than doing
the same via two instructions:
neg t0, t0
sext.w a0, t0
Becomes:
negw t0, t0
Change-Id: I824ab25001bd3304bdbd435e7b244fcc036ef212
Reviewed-on: https://go-review.googlesource.com/c/go/+/652319
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Reviewed-by: Cherry Mui <cherryyz@google.com>
On riscv64, subtraction from a constant is typically implemented as an
ADDI with the negative constant, followed by a negation. However this can
lead to multiple NEG/ADDI/NEG sequences that can be optimised out.
For example, runtime.(*_panic).nextDefer currently contains:
lbu t0, 0(t0)
addi t0, t0, -8
neg t0, t0
addi t0, t0, -7
neg t0, t0
Which is now optimised to:
lbu t0, 0(t0)
addi t0, t0, -1
Change-Id: Idf5815e6db2e3705cc4a4811ca9130a064ae3d80
Reviewed-on: https://go-review.googlesource.com/c/go/+/652318
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Codify the current code generation used on riscv64 in this case.
Change-Id: If4152e3652fc19d0aa28b79dba08abee2486d5ae
Reviewed-on: https://go-review.googlesource.com/c/go/+/652317
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Reviewed-by: David Chase <drchase@google.com>
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Codify the current riscv64 code generation for various subtract from
constant and addition/subtraction tests.
Change-Id: I54ad923280a0578a338bc4431fa5bdc0644c4729
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Tests that exist for riscv64/rva22u64 should also be applied to
riscv64/rva23u64.
Change-Id: Ia529fdf0ac55b8bcb3dcd24fa80efef2351f3842
Reviewed-on: https://go-review.googlesource.com/c/go/+/652315
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Reviewed-by: David Chase <drchase@google.com>
Make the TrailingZeros64 code generation check more specific for 386.
Just checking for BSFL will match both the generic 64 bit decomposition
and the custom 386 lowering.
Change-Id: I62076f1889af0ef1f29704cba01ab419cae0c6e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/656996
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Reviewed-by: Keith Randall <khr@golang.org>
The compiler previously avoided the use of MOVUPS on plan9/amd64. This
was changed in CL 655875, however the codegen tests were not updated
and now fail (seemingly the full codegen tests do not run anywhere,
not even on the longtest builders).
Change-Id: I388b60e7b0911048d4949c5029347f9801c018a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/656997
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Auto-Submit: Keith Randall <khr@google.com>
Decompose Ctz16 and Ctz8 within the SSA rules for LOONG64, MIPS, PPC64
and S390X, rather than having a custom intrinsic. Note that for PPC64 this
actually allows the existing Ctz16 and Ctz8 rules to be used.
Change-Id: I27a5e978f852b9d75396d2a80f5d7dfcb5ef7dd4
Reviewed-on: https://go-review.googlesource.com/c/go/+/651816
Reviewed-by: Paul Murphy <murp@ibm.com>
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Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
While looking at the SSA of following code, i noticed
that these rules do not work properly, and the types
are loaded indirectly through an itab, instead of statically.
type M interface{ M() }
type A interface{ A() }
type Impl struct{}
func (*Impl) M() {}
func (*Impl) A() {}
func main() {
var a M = &Impl{}
a.(A).A()
}
Change-Id: Ia275993f81a2e7302102d4ff87ac28586023d13c
GitHub-Last-Rev: 4bfc901917
GitHub-Pull-Request: golang/go#71784
Reviewed-on: https://go-review.googlesource.com/c/go/+/649500
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Reviewed-by: Michael Knyszek <mknyszek@google.com>
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It currently isn't because it does load/store/load/store/...
Rework to do overwrite processing in pairs so it is instead
load/load/store/store/...
Change-Id: If7be629bc4048da5f2386dafb8f05759b79e9e2b
Reviewed-on: https://go-review.googlesource.com/c/go/+/631495
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Reviewed-by: Keith Randall <khr@google.com>
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Particularly with 2-word load instructions, this becomes important.
Classic example is:
func f(p *string) string {
return *p
}
We want the two loads to put the return values directly into
the two ABI return registers.
At this point in the stack, cmd/go is 1.1% smaller.
Change-Id: I51fd1710238e81d15aab2bfb816d73c8e7c207b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/631137
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Reviewed-by: Keith Randall <khr@google.com>
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Look for possible paired load/store operations on arm64.
I don't expect this would be a lot faster, but it will save
binary space, and indirectly through the icache at least a bit
of time.
Change-Id: I4dd73b0e6329c4659b7453998f9b75320fcf380b
Reviewed-on: https://go-review.googlesource.com/c/go/+/629256
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Reviewed-by: Keith Randall <khr@google.com>
If we call slicebytetostring immediately (with no intervening writes)
before calling map access or delete functions with the resulting
string as the key, then we can just use the ptr/len of the
slicebytetostring argument as the key. This avoids an allocation.
Fixes#44898
Update #71132
There's old code in cmd/compile/internal/walk/order.go that handles
some of these cases.
1. m[string(b)]
2. s := string(b); m[s]
3. m[[2]string{string(b1),string(b2)}]
The old code handled cases 1&3. The new code handles cases 1&2.
We'll leave the old code around to keep 3 working, although it seems
not terribly common.
Case 2 happens particularly after inlining, so it is pretty common.
Change-Id: I8913226ca79d2c65f4e2bd69a38ac8c976a57e43
Reviewed-on: https://go-review.googlesource.com/c/go/+/640656
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
In addition to unsigned loads which already exist.
This helps code that does switches on strings to constant-fold
the switch away when the string being switched on is constant.
Fixes#71699
Change-Id: If3051af0f7255d2a573da6f96b153a987a7f159d
Reviewed-on: https://go-review.googlesource.com/c/go/+/649295
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@google.com>
We can just use == if the interface is direct.
Fixes#70738
Change-Id: Ia9a644791a370fec969c04c42d28a9b58f16911f
Reviewed-on: https://go-review.googlesource.com/c/go/+/635435
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
