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Josh Bleecher Snyder authored
The order pass is responsible for ensuring that values passed to runtime functions, including convT2E/convT2I, are addressable. Prior to this CL, this was always accomplished by creating a temp, which frequently escaped to the heap, causing allocations, perhaps most notably in code like: fmt.Println(1, 2, 3) // allocates three times None of the runtime routines modify the contents of the pointers they receive, so in the case of constants, instead of creating a temp value, we can create a static value. (Marking the static value as read-only provides protection against accidental attempts by the runtime to modify the constant data.) This improves code generation for code like: panic("abc") c <- 2 // c is a chan int which can now simply refer to "abc" and 2, rather than going by way of a temporary. It also allows us to optimize convT2E/convT2I, by recognizing static readonly values and directly constructing the interface. This CL adds ~0.5% to binary size, despite decreasing the size of many functions, because it also adds many static symbols. This binary size regression could be recovered in future (but currently unplanned) work. There is a lot of content-duplication in these symbols; this statement generates six new symbols, three containing an int 1 and three containing a pointer to the string "a": fmt.Println(1, 1, 1, "a", "a", "a") These symbols could be made content-addressable. Furthermore, these symbols are small, so the alignment and naming overhead is large. As with the go.strings section, these symbols could be hidden and have their alignment reduced. The changes to test/live.go make it impossible (at least with current optimization techniques) to place the values being passed to the runtime in static symbols, preserving autotmp creation. Fixes #18704 Benchmarks from fmt and go-kit's logging package: github.com/go-kit/kit/log name old time/op new time/op delta JSONLoggerSimple-8 1.91µs ± 2% 2.11µs ±22% ~ (p=1.000 n=9+10) JSONLoggerContextual-8 2.60µs ± 6% 2.43µs ± 2% -6.29% (p=0.000 n=9+10) Discard-8 101ns ± 2% 34ns ±14% -66.33% (p=0.000 n=10+9) OneWith-8 161ns ± 1% 102ns ±16% -36.78% (p=0.000 n=10+10) TwoWith-8 175ns ± 3% 106ns ± 7% -39.36% (p=0.000 n=10+9) TenWith-8 293ns ± 3% 227ns ±15% -22.44% (p=0.000 n=9+10) LogfmtLoggerSimple-8 704ns ± 2% 608ns ± 2% -13.65% (p=0.000 n=10+9) LogfmtLoggerContextual-8 962ns ± 1% 860ns ±17% -10.57% (p=0.003 n=9+10) NopLoggerSimple-8 188ns ± 1% 120ns ± 1% -36.39% (p=0.000 n=9+10) NopLoggerContextual-8 379ns ± 1% 243ns ± 0% -35.77% (p=0.000 n=9+10) ValueBindingTimestamp-8 577ns ± 1% 499ns ± 1% -13.51% (p=0.000 n=10+10) ValueBindingCaller-8 898ns ± 2% 844ns ± 2% -6.00% (p=0.000 n=10+10) name old alloc/op new alloc/op delta JSONLoggerSimple-8 904B ± 0% 872B ± 0% -3.54% (p=0.000 n=10+10) JSONLoggerContextual-8 1.20kB ± 0% 1.14kB ± 0% -5.33% (p=0.000 n=10+10) Discard-8 64.0B ± 0% 32.0B ± 0% -50.00% (p=0.000 n=10+10) OneWith-8 96.0B ± 0% 64.0B ± 0% -33.33% (p=0.000 n=10+10) TwoWith-8 160B ± 0% 128B ± 0% -20.00% (p=0.000 n=10+10) TenWith-8 672B ± 0% 640B ± 0% -4.76% (p=0.000 n=10+10) LogfmtLoggerSimple-8 128B ± 0% 96B ± 0% -25.00% (p=0.000 n=10+10) LogfmtLoggerContextual-8 304B ± 0% 240B ± 0% -21.05% (p=0.000 n=10+10) NopLoggerSimple-8 128B ± 0% 96B ± 0% -25.00% (p=0.000 n=10+10) NopLoggerContextual-8 304B ± 0% 240B ± 0% -21.05% (p=0.000 n=10+10) ValueBindingTimestamp-8 159B ± 0% 127B ± 0% -20.13% (p=0.000 n=10+10) ValueBindingCaller-8 112B ± 0% 80B ± 0% -28.57% (p=0.000 n=10+10) name old allocs/op new allocs/op delta JSONLoggerSimple-8 19.0 ± 0% 17.0 ± 0% -10.53% (p=0.000 n=10+10) JSONLoggerContextual-8 25.0 ± 0% 21.0 ± 0% -16.00% (p=0.000 n=10+10) Discard-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10) OneWith-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10) TwoWith-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10) TenWith-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10) LogfmtLoggerSimple-8 4.00 ± 0% 2.00 ± 0% -50.00% (p=0.000 n=10+10) LogfmtLoggerContextual-8 7.00 ± 0% 3.00 ± 0% -57.14% (p=0.000 n=10+10) NopLoggerSimple-8 4.00 ± 0% 2.00 ± 0% -50.00% (p=0.000 n=10+10) NopLoggerContextual-8 7.00 ± 0% 3.00 ± 0% -57.14% (p=0.000 n=10+10) ValueBindingTimestamp-8 5.00 ± 0% 3.00 ± 0% -40.00% (p=0.000 n=10+10) ValueBindingCaller-8 4.00 ± 0% 2.00 ± 0% -50.00% (p=0.000 n=10+10) fmt name old time/op new time/op delta SprintfPadding-8 88.9ns ± 3% 79.1ns ± 1% -11.09% (p=0.000 n=10+7) SprintfEmpty-8 12.6ns ± 3% 12.8ns ± 3% ~ (p=0.136 n=10+10) SprintfString-8 38.7ns ± 5% 26.9ns ± 6% -30.65% (p=0.000 n=10+10) SprintfTruncateString-8 56.7ns ± 2% 47.0ns ± 3% -17.05% (p=0.000 n=10+10) SprintfQuoteString-8 164ns ± 2% 153ns ± 2% -7.01% (p=0.000 n=10+10) SprintfInt-8 38.9ns ±15% 26.5ns ± 2% -31.93% (p=0.000 n=10+9) SprintfIntInt-8 60.3ns ± 9% 38.2ns ± 1% -36.67% (p=0.000 n=10+8) SprintfPrefixedInt-8 58.6ns ±13% 51.2ns ±11% -12.66% (p=0.001 n=10+10) SprintfFloat-8 71.4ns ± 3% 64.2ns ± 3% -10.08% (p=0.000 n=8+10) SprintfComplex-8 175ns ± 3% 159ns ± 2% -9.03% (p=0.000 n=10+10) SprintfBoolean-8 33.5ns ± 4% 25.7ns ± 5% -23.28% (p=0.000 n=10+10) SprintfHexString-8 65.3ns ± 3% 51.7ns ± 5% -20.86% (p=0.000 n=10+9) SprintfHexBytes-8 67.2ns ± 5% 67.9ns ± 4% ~ (p=0.383 n=10+10) SprintfBytes-8 129ns ± 7% 124ns ± 7% ~ (p=0.074 n=9+10) SprintfStringer-8 127ns ± 4% 126ns ± 8% ~ (p=0.506 n=9+10) SprintfStructure-8 357ns ± 3% 359ns ± 3% ~ (p=0.469 n=10+10) ManyArgs-8 203ns ± 6% 126ns ± 3% -37.94% (p=0.000 n=10+10) FprintInt-8 119ns ±10% 74ns ± 3% -37.54% (p=0.000 n=10+10) FprintfBytes-8 122ns ± 4% 120ns ± 3% ~ (p=0.124 n=10+10) FprintIntNoAlloc-8 78.2ns ± 5% 74.1ns ± 3% -5.28% (p=0.000 n=10+10) ScanInts-8 349µs ± 1% 349µs ± 0% ~ (p=0.606 n=9+8) ScanRecursiveInt-8 43.8ms ± 7% 40.1ms ± 2% -8.42% (p=0.000 n=10+10) ScanRecursiveIntReaderWrapper-8 43.5ms ± 4% 40.4ms ± 2% -7.16% (p=0.000 n=10+9) name old alloc/op new alloc/op delta SprintfPadding-8 24.0B ± 0% 16.0B ± 0% -33.33% (p=0.000 n=10+10) SprintfEmpty-8 0.00B 0.00B ~ (all equal) SprintfString-8 21.0B ± 0% 5.0B ± 0% -76.19% (p=0.000 n=10+10) SprintfTruncateString-8 32.0B ± 0% 16.0B ± 0% -50.00% (p=0.000 n=10+10) SprintfQuoteString-8 48.0B ± 0% 32.0B ± 0% -33.33% (p=0.000 n=10+10) SprintfInt-8 16.0B ± 0% 1.0B ± 0% -93.75% (p=0.000 n=10+10) SprintfIntInt-8 24.0B ± 0% 3.0B ± 0% -87.50% (p=0.000 n=10+10) SprintfPrefixedInt-8 72.0B ± 0% 64.0B ± 0% -11.11% (p=0.000 n=10+10) SprintfFloat-8 16.0B ± 0% 8.0B ± 0% -50.00% (p=0.000 n=10+10) SprintfComplex-8 48.0B ± 0% 32.0B ± 0% -33.33% (p=0.000 n=10+10) SprintfBoolean-8 8.00B ± 0% 4.00B ± 0% -50.00% (p=0.000 n=10+10) SprintfHexString-8 96.0B ± 0% 80.0B ± 0% -16.67% (p=0.000 n=10+10) SprintfHexBytes-8 112B ± 0% 112B ± 0% ~ (all equal) SprintfBytes-8 96.0B ± 0% 96.0B ± 0% ~ (all equal) SprintfStringer-8 32.0B ± 0% 32.0B ± 0% ~ (all equal) SprintfStructure-8 256B ± 0% 256B ± 0% ~ (all equal) ManyArgs-8 80.0B ± 0% 0.0B -100.00% (p=0.000 n=10+10) FprintInt-8 8.00B ± 0% 0.00B -100.00% (p=0.000 n=10+10) FprintfBytes-8 32.0B ± 0% 32.0B ± 0% ~ (all equal) FprintIntNoAlloc-8 0.00B 0.00B ~ (all equal) ScanInts-8 15.2kB ± 0% 15.2kB ± 0% ~ (p=0.248 n=9+10) ScanRecursiveInt-8 21.6kB ± 0% 21.6kB ± 0% ~ (all equal) ScanRecursiveIntReaderWrapper-8 21.7kB ± 0% 21.7kB ± 0% ~ (all equal) name old allocs/op new allocs/op delta SprintfPadding-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfEmpty-8 0.00 0.00 ~ (all equal) SprintfString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfTruncateString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfQuoteString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfInt-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfIntInt-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10) SprintfPrefixedInt-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfFloat-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfComplex-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfBoolean-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfHexString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) SprintfHexBytes-8 2.00 ± 0% 2.00 ± 0% ~ (all equal) SprintfBytes-8 2.00 ± 0% 2.00 ± 0% ~ (all equal) SprintfStringer-8 4.00 ± 0% 4.00 ± 0% ~ (all equal) SprintfStructure-8 7.00 ± 0% 7.00 ± 0% ~ (all equal) ManyArgs-8 8.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10) FprintInt-8 1.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10) FprintfBytes-8 1.00 ± 0% 1.00 ± 0% ~ (all equal) FprintIntNoAlloc-8 0.00 0.00 ~ (all equal) ScanInts-8 1.60k ± 0% 1.60k ± 0% ~ (all equal) ScanRecursiveInt-8 1.71k ± 0% 1.71k ± 0% ~ (all equal) ScanRecursiveIntReaderWrapper-8 1.71k ± 0% 1.71k ± 0% ~ (all equal) Change-Id: I7ba72a25fea4140a0ba40a9f443103ed87cc69b5 Reviewed-on: https://go-review.googlesource.com/35554 Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by:
Keith Randall <khr@golang.org>
c682d323