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| author | Josh Bleecher Snyder <josharian@gmail.com> | 2019-04-11 12:18:10 -0700 |
|---|---|---|
| committer | Josh Bleecher Snyder <josharian@gmail.com> | 2019-04-19 15:40:42 +0000 |
| commit | 4aeac68c92c5b79d098aaa7fba168d4c943541ba (patch) | |
| tree | 4583eb98e3b70309bbc8f5129c859114f5c8f066 /src/runtime/funcdata.h | |
| parent | c1544ff906c3696774152aaa6594d6cefce15552 (diff) | |
| download | go-4aeac68c92c5b79d098aaa7fba168d4c943541ba.tar.xz | |
runtime, cmd/compile: re-order PCDATA and FUNCDATA indices
The pclntab encoding supports writing only some PCDATA and FUNCDATA values.
However, the encoding is dense: The max index in use determines the space used.
We should thus choose a numbering in which frequently used indices are smaller.
This change re-orders the PCDATA and FUNCDATA indices using that principle,
using a quick and dirty instrumentation to measure index frequency.
It shrinks binaries by about 0.5%.
Updates #6853
file before after Δ %
go 14745044 14671316 -73728 -0.500%
addr2line 4305128 4280552 -24576 -0.571%
api 6095800 6058936 -36864 -0.605%
asm 4930928 4906352 -24576 -0.498%
buildid 2881520 2861040 -20480 -0.711%
cgo 4896584 4867912 -28672 -0.586%
compile 25868408 25770104 -98304 -0.380%
cover 5319656 5286888 -32768 -0.616%
dist 3654528 3634048 -20480 -0.560%
doc 4719672 4691000 -28672 -0.607%
fix 3418312 3393736 -24576 -0.719%
link 6137952 6109280 -28672 -0.467%
nm 4250536 4225960 -24576 -0.578%
objdump 4665192 4636520 -28672 -0.615%
pack 2297488 2285200 -12288 -0.535%
pprof 14735332 14657508 -77824 -0.528%
test2json 2834952 2818568 -16384 -0.578%
trace 11679964 11618524 -61440 -0.526%
vet 8452696 8403544 -49152 -0.581%
Change-Id: I30665dce57ec7a52e7d3c6718560b3aa5b83dd0b
Reviewed-on: https://go-review.googlesource.com/c/go/+/171760
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Diffstat (limited to 'src/runtime/funcdata.h')
| -rw-r--r-- | src/runtime/funcdata.h | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/src/runtime/funcdata.h b/src/runtime/funcdata.h index 1ee67c8683..d9a35c51a0 100644 --- a/src/runtime/funcdata.h +++ b/src/runtime/funcdata.h @@ -8,15 +8,15 @@ // // These must agree with symtab.go and ../cmd/internal/objabi/funcdata.go. -#define PCDATA_StackMapIndex 0 -#define PCDATA_InlTreeIndex 1 -#define PCDATA_RegMapIndex 2 +#define PCDATA_RegMapIndex 0 +#define PCDATA_StackMapIndex 1 +#define PCDATA_InlTreeIndex 2 #define FUNCDATA_ArgsPointerMaps 0 /* garbage collector blocks */ #define FUNCDATA_LocalsPointerMaps 1 -#define FUNCDATA_InlTree 2 -#define FUNCDATA_RegPointerMaps 3 -#define FUNCDATA_StackObjects 4 +#define FUNCDATA_RegPointerMaps 2 +#define FUNCDATA_StackObjects 3 +#define FUNCDATA_InlTree 4 // Pseudo-assembly statements. |