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2015-02-04cmd/gc: don't copy string in range []byte(str)Dmitry Vyukov
Using benchmark from the issue: benchmark old ns/op new ns/op delta BenchmarkRangeStringCast 2162 1152 -46.72% benchmark old allocs new allocs delta BenchmarkRangeStringCast 1 0 -100.00% Fixes #2204 Change-Id: I92c5edd2adca4a7b6fba00713a581bf49dc59afe Reviewed-on: https://go-review.googlesource.com/3790 Reviewed-by: Keith Randall <khr@golang.org>
2015-01-28cmd/gc: allocate stack buffer for ORUNESTRDmitry Vyukov
If result of string(i) does not escape, allocate a [4]byte temp on stack for it. Change-Id: If31ce9447982929d5b3b963fd0830efae4247c37 Reviewed-on: https://go-review.googlesource.com/3411 Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28cmd/gc: allocate buffers for non-escaped strings on stackDmitry Vyukov
Currently we always allocate string buffers in heap. For example, in the following code we allocate a temp string just for comparison: if string(byteSlice) == "abc" { ... } This change extends escape analysis to cover []byte->string conversions and string concatenation. If the result of operations does not escape, compiler allocates a small buffer on stack and passes it to slicebytetostring and concatstrings. Then runtime uses the buffer if the result fits into it. Size of the buffer is 32 bytes. There is no fundamental theory behind this number. Just an observation that on std lib tests/benchmarks frequency of string allocation is inversely proportional to string length; and there is significant number of allocations up to length 32. benchmark old allocs new allocs delta BenchmarkFprintfBytes 2 1 -50.00% BenchmarkDecodeComplex128Slice 318 316 -0.63% BenchmarkDecodeFloat64Slice 318 316 -0.63% BenchmarkDecodeInt32Slice 318 316 -0.63% BenchmarkDecodeStringSlice 2318 2316 -0.09% BenchmarkStripTags 11 5 -54.55% BenchmarkDecodeGray 111 102 -8.11% BenchmarkDecodeNRGBAGradient 200 188 -6.00% BenchmarkDecodeNRGBAOpaque 165 152 -7.88% BenchmarkDecodePaletted 319 309 -3.13% BenchmarkDecodeRGB 166 157 -5.42% BenchmarkDecodeInterlacing 279 268 -3.94% BenchmarkGoLookupIP 153 135 -11.76% BenchmarkGoLookupIPNoSuchHost 508 466 -8.27% BenchmarkGoLookupIPWithBrokenNameServer 245 226 -7.76% BenchmarkClientServerParallel4 62 61 -1.61% BenchmarkClientServerParallel64 62 61 -1.61% BenchmarkClientServerParallelTLS4 79 78 -1.27% BenchmarkClientServerParallelTLS64 112 111 -0.89% benchmark old ns/op new ns/op delta BenchmarkFprintfBytes 381 311 -18.37% BenchmarkStripTags 2615 2351 -10.10% BenchmarkDecodeNRGBAGradient 3715887 3635096 -2.17% BenchmarkDecodeNRGBAOpaque 3047645 2928644 -3.90% BenchmarkGoLookupIP 153 135 -11.76% BenchmarkGoLookupIPNoSuchHost 508 466 -8.27% Change-Id: I9ec01da816945c3329d7be3c7794b520418c3f99 Reviewed-on: https://go-review.googlesource.com/3120 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28cmd/gc: don't copy []byte during string comparisonDmitry Vyukov
Currently we allocate a new string during []byte->string conversion in string comparison expressions. String allocation is unnecessary in this case, because comparison does memorize the strings for later use. This change uses slicebytetostringtmp to construct temp string directly from []byte buffer and passes it to runtime.eqstring. Change-Id: If00f1faaee2076baa6f6724d245d5b5e0f59b563 Reviewed-on: https://go-review.googlesource.com/3410 Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-27cmd/gc: don't copy []byte during string concatenationDmitry Vyukov
Consider the following code: s := "(" + string(byteSlice) + ")" Currently we allocate a new string during []byte->string conversion, and pass it to concatstrings. String allocation is unnecessary in this case, because concatstrings does memorize the strings for later use. This change uses slicebytetostringtmp to construct temp string directly from []byte buffer and passes it to concatstrings. I've found few such cases in std lib: s += string(msg[off:off+c]) + "." buf.WriteString("Sec-WebSocket-Accept: " + string(c.accept) + "\r\n") bw.WriteString("Sec-WebSocket-Key: " + string(nonce) + "\r\n") err = xml.Unmarshal([]byte("<Top>"+string(data)+"</Top>"), &logStruct) d.err = d.syntaxError("invalid XML name: " + string(b)) return m, ProtocolError("malformed MIME header line: " + string(kv)) But there are much more in our internal code base. Change-Id: I42f401f317131237ddd0cb9786b0940213af16fb Reviewed-on: https://go-review.googlesource.com/3163 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Russ Cox <rsc@golang.org>
2014-12-29runtime: remove go prefix from a few routinesKeith Randall
They are no longer needed now that C is gone. goatoi -> atoi gofuncname/funcname -> funcname/cfuncname goroundupsize -> already existing roundupsize Change-Id: I278bc33d279e1fdc5e8a2a04e961c4c1573b28c7 Reviewed-on: https://go-review.googlesource.com/2154 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Reviewed-by: Minux Ma <minux@golang.org>
2014-12-28runtime: rename gothrow to throwKeith Randall
Rename "gothrow" to "throw" now that the C version of "throw" is no longer needed. This change is purely mechanical except in panic.go where the old version of "throw" has been deleted. sed -i "" 's/[[:<:]]gothrow[[:>:]]/throw/g' runtime/*.go Change-Id: Icf0752299c35958b92870a97111c67bcd9159dc3 Reviewed-on: https://go-review.googlesource.com/2150 Reviewed-by: Minux Ma <minux@golang.org> Reviewed-by: Dave Cheney <dave@cheney.net>
2014-11-14[dev.cc] all: merge dev.power64 (7667e41f3ced) into dev.ccRuss Cox
This is to reduce the delta between dev.cc and dev.garbage to just garbage collector changes. These are the files that had merge conflicts and have been edited by hand: malloc.go mem_linux.go mgc.go os1_linux.go proc1.go panic1.go runtime1.go LGTM=austin R=austin CC=golang-codereviews https://golang.org/cl/174180043
2014-11-11[dev.cc] runtime: convert memory allocator and garbage collector to GoRuss Cox
The conversion was done with an automated tool and then modified only as necessary to make it compile and run. [This CL is part of the removal of C code from package runtime. See golang.org/s/dev.cc for an overview.] LGTM=r R=r CC=austin, dvyukov, golang-codereviews, iant, khr https://golang.org/cl/167540043
2014-10-22[dev.power64] all: merge default into dev.power64Austin Clements
This brings dev.power64 up-to-date with the current tip of default. go_bootstrap is still panicking with a bad defer when initializing the runtime (even on amd64). LGTM=rsc R=rsc CC=golang-codereviews https://golang.org/cl/152570049
2014-10-22build: merge the great pkg/ rename into dev.power64Austin Clements
This also removes pkg/runtime/traceback_lr.c, which was ported to Go in an earlier commit and then moved to runtime/traceback.go. Reviewer: rsc@golang.org rsc: LGTM
2014-09-16runtime: remove duplicated Go constantsRuss Cox
The C header files are the single point of truth: every C enum constant Foo is available to Go as _Foo. Remove or redirect duplicate Go declarations so they cannot be out of sync. Eventually we will need to put constants in Go, but for now having them be out of sync with C is too risky. These predate the build support for auto-generating Go constants from the C definitions. LGTM=iant R=iant CC=golang-codereviews https://golang.org/cl/141510043
2014-09-09runtime: merge mallocgc, gomallocgcRuss Cox
I assumed they were the same when I wrote cgocallback.go earlier today. Merge them to eliminate confusion. I can't tell what gomallocgc did before with a nil type but without FlagNoScan. I created a call like that in cgocallback.go this morning, translating from a C file. It was supposed to do what the C version did, namely treat the block conservatively. Now it will. LGTM=khr R=khr CC=golang-codereviews https://golang.org/cl/141810043
2014-09-08liblink, runtime: diagnose and fix C code running on Go stackRuss Cox
This CL contains compiler+runtime changes that detect C code running on Go (not g0, not gsignal) stacks, and it contains corrections for what it detected. The detection works by changing the C prologue to use a different stack guard word in the G than Go prologue does. On the g0 and gsignal stacks, that stack guard word is set to the usual stack guard value. But on ordinary Go stacks, that stack guard word is set to ^0, which will make any stack split check fail. The C prologue then calls morestackc instead of morestack, and morestackc aborts the program with a message about running C code on a Go stack. This check catches all C code running on the Go stack except NOSPLIT code. The NOSPLIT code is allowed, so the check is complete. Since it is a dynamic check, the code must execute to be caught. But unlike the static checks we've been using in cmd/ld, the dynamic check works with function pointers and other indirect calls. For example it caught sigpanic being pushed onto Go stacks in the signal handlers. Fixes #8667. LGTM=khr, iant R=golang-codereviews, khr, iant CC=golang-codereviews, r https://golang.org/cl/133700043
2014-09-08build: move package sources from src/pkg to srcRuss Cox
Preparation was in CL 134570043. This CL contains only the effect of 'hg mv src/pkg/* src'. For more about the move, see golang.org/s/go14nopkg.