diff options
author | naruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2016-03-14 10:14:48 +0000 |
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committer | naruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2016-03-14 10:14:48 +0000 |
commit | 3d5a3a236d99e7512955947be832b343b18b024c (patch) | |
tree | e8fcfe451d3ddae98729599c399ae027da4dadf9 | |
parent | 4b15b54d680bbb6e97673e67085ed4f70b612ccb (diff) | |
download | ruby-3d5a3a236d99e7512955947be832b343b18b024c.tar.gz |
* bignum.c (big2str_2bdigits): reduce div instruction.
Fix the code so that C compiler unify div instructions of `%` and `/`.
Before:
4291b0: 48 89 f0 mov %rsi,%rax
4291b3: 31 d2 xor %edx,%edx
4291b5: 48 83 ef 01 sub $0x1,%rdi
4291b9: 48 f7 f1 div %rcx # <---- !
4291bc: 41 0f b6 04 11 movzbl (%r9,%rdx,1),%eax
4291c1: 31 d2 xor %edx,%edx
4291c3: 41 88 04 38 mov %al,(%r8,%rdi,1)
4291c7: 48 63 4b 04 movslq 0x4(%rbx),%rcx
4291cb: 48 89 f0 mov %rsi,%rax
4291ce: 48 f7 f1 div %rcx # <---- !
4291d1: 48 89 c6 mov %rax,%rsi
4291d4: 48 85 ff test %rdi,%rdi
4291d7: 75 d7 jne 4291b0 <big2str_2bdigits+0x50>
4291d9: 48 63 6b 10 movslq 0x10(%rbx),%rbp
4291dd: 48 01 6b 20 add %rbp,0x20(%rbx)
4291e1: 48 8b 44 24 48 mov 0x48(%rsp),%rax
4291e6: 64 48 33 04 25 28 00 xor %fs:0x28,%rax
After:
4291b0: 48 63 73 04 movslq 0x4(%rbx),%rsi
4291b4: 31 d2 xor %edx,%edx
4291b6: 48 83 e9 01 sub $0x1,%rcx
4291ba: 48 f7 f6 div %rsi # <---- !
4291bd: 41 0f b6 14 10 movzbl (%r8,%rdx,1),%edx
4291c2: 88 14 0f mov %dl,(%rdi,%rcx,1)
4291c5: 48 85 c9 test %rcx,%rcx
4291c8: 75 e6 jne 4291b0 <big2str_2bdigits+0x50>
4291ca: 48 63 6b 10 movslq 0x10(%rbx),%rbp
4291ce: 48 01 6b 20 add %rbp,0x20(%rbx)
4291d2: 48 8b 44 24 48 mov 0x48(%rsp),%rax
4291d7: 64 48 33 04 25 28 00 xor %fs:0x28,%rax
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54102 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
-rw-r--r-- | ChangeLog | 4 | ||||
-rw-r--r-- | bignum.c | 6 |
2 files changed, 8 insertions, 2 deletions
@@ -1,3 +1,7 @@ +Mon Mar 14 19:05:39 2016 NARUSE, Yui <naruse@ruby-lang.org> + + * bignum.c (big2str_2bdigits): reduce div instruction. + Mon Mar 14 18:39:53 2016 Martin Duerst <duerst@it.aoyama.ac.jp> * include/ruby/oniguruma.h, enc/unicode.c: Adjusting flag assignments @@ -4615,8 +4615,9 @@ big2str_2bdigits(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t tail p = buf; j = sizeof(buf); do { - p[--j] = ruby_digitmap[num % b2s->base]; + BDIGIT_DBL idx = num % b2s->base; num /= b2s->base; + p[--j] = ruby_digitmap[idx]; } while (num); len = sizeof(buf) - j; big2str_alloc(b2s, len + taillen); @@ -4626,8 +4627,9 @@ big2str_2bdigits(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t tail p = b2s->ptr; j = b2s->hbase2_numdigits; do { - p[--j] = ruby_digitmap[num % b2s->base]; + BDIGIT_DBL idx = num % b2s->base; num /= b2s->base; + p[--j] = ruby_digitmap[idx]; } while (j); len = b2s->hbase2_numdigits; } |