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Groups > comp.lang.forth > #25551
| Newsgroups | comp.lang.forth |
|---|---|
| Date | 2013-09-07 03:22 -0700 |
| References | <ade7108a-663a-47e3-91d2-d913082f6c10@googlegroups.com> |
| Message-ID | <b9f07f9f-9281-4a9d-a17b-e2e62ea43347@googlegroups.com> (permalink) |
| Subject | Re: RAFTS-like optimiser; progress report |
| From | mhx@iae.nl |
On Friday, September 6, 2013 11:12:06 PM UTC+2, Alex McDonald wrote: > Here's an example of the intermediate code generated. The first is an > insertion in a doubly linked list, and the second is the same code > optimised at the Forth level to reduce fetches. (Comments have been > added by me.) The intermediate code for both is identical. [..] > begin-structure node% > field: node.next \ next in linked list (or head) > field: node.prev \ prev in linked list (or tail) > end-structure [..] Here is what the iForth codegenerator makes of it: FORTH> : node-after ( free linked -- ) ( insert free node after linked ) <3>[FORTH>] 2dup node.next @ node.prev ! <3>[FORTH>] 2dup node.next @ swap node.next ! <3>[FORTH>] 2dup node.next ! swap node.prev ! ; ok FORTH> ' node-after idis $01408940 : node-after $0140894A pop rbx $0140894B pop rdi $0140894C mov rax, [rbx] qword $0140894F mov [rax 8 +] qword, rdi $01408953 mov rax, [rbx] qword $01408956 mov [rdi] qword, rax $01408959 mov [rbx] qword, rdi $0140895C mov [rdi 8 +] qword, rbx $01408960 ; Note the redundant reload of rax (the optimizer detected an intervening ! that it doesn't know how to track). FORTH> : node-after ( free linked -- ) ( insert free node after linked ) Redefining node-after <3>[FORTH>] 2dup node.next 2dup @ 2dup <3>[FORTH>] node.prev ! swap node.next ! ! swap node.prev ! ; ok FORTH> ' node-after idis $014089C0 : node-after $014089CA pop rbx $014089CB pop rdi $014089CC mov rax, [rbx] qword $014089CF mov rdx, [rbx] qword $014089D2 mov [rax 8 +] qword, rdi $014089D6 mov [rdi] qword, rdx $014089D9 mov [rbx] qword, rdi $014089DC mov [rdi 8 +] qword, rbx $014089E0 ; ok Instead of reloading rax, here rdx is loaded with the same value. Not a really significant improvement for the time and obscurity invested at the Forth level. Finally, what happens when the code actually executes: FORTH> 8 node% %allot constant linked FORTH> 8 node% %allot constant free FORTH> : tt free linked node-after ; ok FORTH> ' tt idis $014092C0 : tt $014092CA mov rax, $014089B0 qword-offset $014092D1 mov [rax 8 +] qword, $01408E30 d# $014092D9 mov rbx, $014089B0 qword-offset $014092E0 mov $01408E30 qword-offset, rbx $014092E7 mov $014089B0 qword-offset, $01408E30 d# $014092F2 mov $01408E38 qword-offset, $014089B0 d# $014092FD ; It is certainly debatable if the expansion to literals is helpful. In more complicated code it would free up a few registers. -marcel
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RAFTS-like optimiser; progress report Alex McDonald <blog@rivadpm.com> - 2013-09-06 14:12 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-06 16:54 -0500
Re: RAFTS-like optimiser; progress report Alex McDonald <blog@rivadpm.com> - 2013-09-06 16:02 -0700
Re: RAFTS-like optimiser; progress report Bernd Paysan <bernd.paysan@gmx.de> - 2013-09-07 03:01 +0200
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-07 03:21 -0500
Re: RAFTS-like optimiser; progress report albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-09-07 19:56 +0000
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-07 15:06 +0000
Re: RAFTS-like optimiser; progress report "Alex McDonald" <blog@rivadpm.com> - 2013-09-07 19:01 +0100
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-09 12:23 +0000
Re: RAFTS-like optimiser; progress report "Alex McDonald" <blog@rivadpm.com> - 2013-09-10 12:01 +0100
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-10 12:45 +0000
Re: RAFTS-like optimiser; progress report "Alex McDonald" <blog@rivadpm.com> - 2013-09-10 16:33 +0100
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-11 15:02 +0000
Re: RAFTS-like optimiser; progress report "Alex McDonald" <blog@rivadpm.com> - 2013-09-11 17:44 +0100
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-13 11:58 +0000
Re: RAFTS-like optimiser; progress report "Rod Pemberton" <dont_use_email@nohavenotit.com> - 2013-09-14 22:47 -0400
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-15 16:05 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-07 16:08 -0500
Re: RAFTS-like optimiser; progress report mhx@iae.nl - 2013-09-08 03:21 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-08 06:42 -0500
Re: RAFTS-like optimiser; progress report mhx@iae.nl - 2013-09-08 04:51 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-08 07:02 -0500
Re: RAFTS-like optimiser; progress report Paul Rubin <no.email@nospam.invalid> - 2013-09-08 10:08 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-08 12:47 -0500
Re: RAFTS-like optimiser; progress report Paul Rubin <no.email@nospam.invalid> - 2013-09-08 11:10 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-08 15:16 -0500
Re: RAFTS-like optimiser; progress report Paul Rubin <no.email@nospam.invalid> - 2013-09-08 16:08 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-09 04:57 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-09 12:41 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-09 08:56 -0500
Re: RAFTS-like optimiser; progress report albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-09-09 14:20 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-09 09:27 -0500
Re: RAFTS-like optimiser; progress report "Rod Pemberton" <dont_use_email@nohavenotit.com> - 2013-09-10 04:31 -0400
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-10 05:11 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-09 15:08 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-09 10:45 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-11 15:21 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-11 12:04 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-11 17:46 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-11 14:45 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-13 13:00 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-13 10:46 -0500
Re: RAFTS-like optimiser; progress report stephenXXX@mpeforth.com (Stephen Pelc) - 2013-09-13 17:44 +0000
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-14 15:31 +0000
Re: RAFTS-like optimiser; progress report Paul Rubin <no.email@nospam.invalid> - 2013-09-14 10:33 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-14 12:39 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-15 15:05 +0000
Re: RAFTS-like optimiser; progress report Alex McDonald <blog@rivadpm.com> - 2013-09-15 08:32 -0700
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-15 13:20 -0500
Re: RAFTS-like optimiser; progress report stephenXXX@mpeforth.com (Stephen Pelc) - 2013-09-15 16:54 +0000
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-15 17:02 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-15 12:54 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-16 09:21 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-16 08:39 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-16 15:48 +0000
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-16 15:03 -0500
Re: RAFTS-like optimiser; progress report anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-09-17 10:15 +0000
Re: RAFTS-like optimiser; progress report "Rod Pemberton" <dont_use_email@nohavenotit.com> - 2013-09-17 17:24 -0400
Re: RAFTS-like optimiser; progress report stephenXXX@mpeforth.com (Stephen Pelc) - 2013-09-17 13:10 +0000
Re: RAFTS-like optimiser; progress report "Rod Pemberton" <dont_use_email@nohavenotit.com> - 2013-09-10 04:30 -0400
Re: RAFTS-like optimiser; progress report Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-09-10 05:14 -0500
Re: RAFTS-like optimiser; progress report mhx@iae.nl - 2013-09-07 03:22 -0700
Re: RAFTS-like optimiser; progress report mhx@iae.nl - 2013-09-07 03:32 -0700
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