digitalmars.D - Help with a DMD patch
- Vladimir Panteleev (12/12) Mar 16 2013 I'm trying to cut my teeth on DMD hacking with a simple
- Igor Stepanov (2/2) Mar 16 2013 What do the lines el_combine? I do not see them in the code
- Vladimir Panteleev (6/8) Mar 16 2013 Greetings Igor,
- Igor Stepanov (19/27) Mar 16 2013 Visually, it should work :)
- Vladimir Panteleev (11/43) Mar 16 2013 Dynamic arrays work perfectly, it's the static ones I'm having
- Igor Stepanov (5/49) Mar 16 2013 Probably a stupid question, but why do you want to use el_same?
- Vladimir Panteleev (4/7) Mar 16 2013 As I understand, one "elem" can appear only once in the backend
- Daniel Murphy (7/18) Mar 16 2013 Instead of copying elems, try to generate something like this:
- Vladimir Panteleev (4/26) Mar 17 2013 That's pretty much what my first attempt was. It asserts when I
- Martin Nowak (5/6) Mar 18 2013 Yeah, that's why I wished more of this would move to druntime, but the
- Vladimir Panteleev (4/11) Mar 18 2013 Thanks, I've already tracked it down to a pre-existing DMD bug.
- Jacob Carlborg (4/6) Mar 19 2013 Put it in some other file and add a public import to object.di.
- Vladimir Panteleev (7/8) Mar 18 2013 Gaaah! My test program doesn't compile even without my patches!
- Vladimir Panteleev (1/1) Mar 18 2013 https://github.com/D-Programming-Language/dmd/pull/1766
I'm trying to cut my teeth on DMD hacking with a simple optimization ( http://d.puremagic.com/issues/show_bug.cgi?id=9477 ), but not having much luck so far - the backend is rejecting my attempts with asserts here or there. Since the asserts have no error messages, and the code is very terse, often un-straightforward and lacking in comments, I have no idea if I'm feeding it bad input or if it's some latent bug. Here's my work so far: https://github.com/CyberShadow/dmd/compare/fix9477-work Could a DMD guru have a look and tell me what I'm doing wrong? Tests: https://gist.github.com/CyberShadow/5177509
Mar 16 2013
What do the lines el_combine? I do not see them in the code structure comparison.
Mar 16 2013
On Saturday, 16 March 2013 at 21:15:32 UTC, Igor Stepanov wrote:What do the lines el_combine? I do not see them in the code structure comparison.Greetings Igor, The el_combine calls are supposed to ensure correct order of evaluation. I based that code from this fragment: https://github.com/D-Programming-Language/dmd/blob/635c6b07/src/e2ir.c#L2702
Mar 16 2013
On Saturday, 16 March 2013 at 21:21:51 UTC, Vladimir Panteleev wrote:On Saturday, 16 March 2013 at 21:15:32 UTC, Igor Stepanov wrote:Visually, it should work :) I would try to make sure that the various components of expression are correctly calculated. In particular, I am concerned the calculation of the length of a dynamic array. You can try to do so, that would return the length of the entire expression. / ***** In DMD ***** / if (t1->ty == Tarray) { retrun el_una(I64 ? OP128_64 : OP64_32, TYsize_t, el_same(&earr1)); } / ***** In D ***** / int[] arr = [1,2,3]; int[] arr3 = [1,2,3,4,5]; size_t len = cast(size_t)(arr == arr3); assert(len == arr.length);What do the lines el_combine? I do not see them in the code structure comparison.Greetings Igor, The el_combine calls are supposed to ensure correct order of evaluation. I based that code from this fragment: https://github.com/D-Programming-Language/dmd/blob/635c6b07/src/e2ir.c#L2702
Mar 16 2013
On Saturday, 16 March 2013 at 21:42:31 UTC, Igor Stepanov wrote:On Saturday, 16 March 2013 at 21:21:51 UTC, Vladimir Panteleev wrote:Dynamic arrays work perfectly, it's the static ones I'm having trouble with... particularly, when they're being returned from a function. From what I can tell, the situation is that I can neither copy them using el_same (it neither makes sense, as the arrays can be large, nor does the compiler let me to), nor can I take their address, because the code generator fails to process an OPaddr elem when its child is a function call. However, the same thing seems to work when calling the runtime function for array equality (the current implementation)...On Saturday, 16 March 2013 at 21:15:32 UTC, Igor Stepanov wrote:Visually, it should work :) I would try to make sure that the various components of expression are correctly calculated. In particular, I am concerned the calculation of the length of a dynamic array. You can try to do so, that would return the length of the entire expression. / ***** In DMD ***** / if (t1->ty == Tarray) { retrun el_una(I64 ? OP128_64 : OP64_32, TYsize_t, el_same(&earr1)); } / ***** In D ***** / int[] arr = [1,2,3]; int[] arr3 = [1,2,3,4,5]; size_t len = cast(size_t)(arr == arr3); assert(len == arr.length);What do the lines el_combine? I do not see them in the code structure comparison.Greetings Igor, The el_combine calls are supposed to ensure correct order of evaluation. I based that code from this fragment: https://github.com/D-Programming-Language/dmd/blob/635c6b07/src/e2ir.c#L2702
Mar 16 2013
On Saturday, 16 March 2013 at 21:49:33 UTC, Vladimir Panteleev wrote:On Saturday, 16 March 2013 at 21:42:31 UTC, Igor Stepanov wrote:Probably a stupid question, but why do you want to use el_same? As I understand it, el_same creates a copy. Why not use the original, if we know that it will not change anything.On Saturday, 16 March 2013 at 21:21:51 UTC, Vladimir Panteleev wrote:Dynamic arrays work perfectly, it's the static ones I'm having trouble with... particularly, when they're being returned from a function. From what I can tell, the situation is that I can neither copy them using el_same (it neither makes sense, as the arrays can be large, nor does the compiler let me to), nor can I take their address, because the code generator fails to process an OPaddr elem when its child is a function call. However, the same thing seems to work when calling the runtime function for array equality (the current implementation)...On Saturday, 16 March 2013 at 21:15:32 UTC, Igor Stepanov wrote:Visually, it should work :) I would try to make sure that the various components of expression are correctly calculated. In particular, I am concerned the calculation of the length of a dynamic array. You can try to do so, that would return the length of the entire expression. / ***** In DMD ***** / if (t1->ty == Tarray) { retrun el_una(I64 ? OP128_64 : OP64_32, TYsize_t, el_same(&earr1)); } / ***** In D ***** / int[] arr = [1,2,3]; int[] arr3 = [1,2,3,4,5]; size_t len = cast(size_t)(arr == arr3); assert(len == arr.length);What do the lines el_combine? I do not see them in the code structure comparison.Greetings Igor, The el_combine calls are supposed to ensure correct order of evaluation. I based that code from this fragment: https://github.com/D-Programming-Language/dmd/blob/635c6b07/src/e2ir.c#L2702
Mar 16 2013
"Vladimir Panteleev" <vladimir thecybershadow.net> On Saturday, 16 March 2013 at 22:14:22 UTC, Igor Stepanov wrote:Probably a stupid question, but why do you want to use el_same? As I understand it, el_same creates a copy. Why not use the original, if we know that it will not change anything.As I understand, one "elem" can appear only once in the backend tree. When I tried otherwise, I got asserts in the optimizer, and I've never seen code that reuses elem nodes.
Mar 16 2013
"Vladimir Panteleev" <vladimir thecybershadow.net> wrote in message news:pzqxkiigdvvicqkqahpn forum.dlang.org...I'm trying to cut my teeth on DMD hacking with a simple optimization ( http://d.puremagic.com/issues/show_bug.cgi?id=9477 ), but not having much luck so far - the backend is rejecting my attempts with asserts here or there. Since the asserts have no error messages, and the code is very terse, often un-straightforward and lacking in comments, I have no idea if I'm feeding it bad input or if it's some latent bug. Here's my work so far: https://github.com/CyberShadow/dmd/compare/fix9477-work Could a DMD guru have a look and tell me what I'm doing wrong? Tests: https://gist.github.com/CyberShadow/5177509Instead of copying elems, try to generate something like this: (auto tmp1 = e1, auto tmp2 = e2, tmp1.length == tmp2.length && !memcmp(tmp1.ptr, tmp2.ptr)) There is code in e2ir that already does stuff like this. Not really the easiest part of dmd to hack on....
Mar 16 2013
On Sunday, 17 March 2013 at 02:35:30 UTC, Daniel Murphy wrote:"Vladimir Panteleev" <vladimir thecybershadow.net> wrote in message news:pzqxkiigdvvicqkqahpn forum.dlang.org...That's pretty much what my first attempt was. It asserts when I try to save a temporary copy of a static array. Also, it is undesirable if the array happens to be large...I'm trying to cut my teeth on DMD hacking with a simple optimization ( http://d.puremagic.com/issues/show_bug.cgi?id=9477 ), but not having much luck so far - the backend is rejecting my attempts with asserts here or there. Since the asserts have no error messages, and the code is very terse, often un-straightforward and lacking in comments, I have no idea if I'm feeding it bad input or if it's some latent bug. Here's my work so far: https://github.com/CyberShadow/dmd/compare/fix9477-work Could a DMD guru have a look and tell me what I'm doing wrong? Tests: https://gist.github.com/CyberShadow/5177509Instead of copying elems, try to generate something like this: (auto tmp1 = e1, auto tmp2 = e2, tmp1.length == tmp2.length && !memcmp(tmp1.ptr, tmp2.ptr))
Mar 17 2013
On 03/17/2013 03:35 AM, Daniel Murphy wrote:Not really the easiest part of dmd to hack on....Yeah, that's why I wished more of this would move to druntime, but the current solution to stuff everything into object.di doesn't scale too well. Looking at "a[] = b[]" => memcpy might help. https://github.com/D-Programming-Language/dmd/blob/6b634f369a53cdc297d0f41c50d03f8b091ea074/src/e2ir.c#L2824
Mar 18 2013
On Monday, 18 March 2013 at 21:10:15 UTC, Martin Nowak wrote:On 03/17/2013 03:35 AM, Daniel Murphy wrote:Thanks, I've already tracked it down to a pre-existing DMD bug. Many of my previous attempts were actually correct. I submitted the pull request just now.Not really the easiest part of dmd to hack on....Yeah, that's why I wished more of this would move to druntime, but the current solution to stuff everything into object.di doesn't scale too well. Looking at "a[] = b[]" => memcpy might help. https://github.com/D-Programming-Language/dmd/blob/6b634f369a53cdc297d0f41c50d03f8b091ea074/src/e2ir.c#L2824
Mar 18 2013
On 2013-03-18 22:10, Martin Nowak wrote:Yeah, that's why I wished more of this would move to druntime, but the current solution to stuff everything into object.di doesn't scale too well.Put it in some other file and add a public import to object.di. -- /Jacob Carlborg
Mar 19 2013
On Saturday, 16 March 2013 at 18:15:06 UTC, Vladimir Panteleev wrote:Could a DMD guru have a look and tell me what I'm doing wrong?Gaaah! My test program doesn't compile even without my patches! I was fighting against pre-existing bugs in DMD... Even more embarrassing, is that I had found and filed this bug myself: http://d.puremagic.com/issues/show_bug.cgi?id=9402
Mar 18 2013