Am 07.07.22 um 21:11 schrieb René Scharfe: > Am 07.07.22 um 20:10 schrieb Junio C Hamano: >> @@ >> type T; >> T *dst_ptr; >> T *src_ptr; >> T[] dst_arr; >> T[] src_arr; >> expression n; >> @@ >> ( >> - memcpy(dst_ptr, src_ptr, (n) * sizeof(T)) >> + COPY_ARRAY(dst_ptr, src_ptr, n) >> | >> - memcpy(dst_ptr, src_arr, (n) * sizeof(T)) >> + COPY_ARRAY(dst_ptr, src_arr, n) >> | >> - memcpy(dst_arr, src_ptr, (n) * sizeof(T)) >> + COPY_ARRAY(dst_arr, src_ptr, n) >> | >> - memcpy(dst_arr, src_arr, (n) * sizeof(T)) >> + COPY_ARRAY(dst_arr, src_arr, n) >> ) >> >> I take it that thanks to the earlier "meh -- between sizeof(*p) and >> sizeof(p[0]) there is no reason to prefer one over the other" and >> "oh, no, we should prefer sizeof(*p) not sizeof(typeof(*p)) but this >> one is the other way around" rules, this one only has to deal with >> sizeof(T). >> >> Am I reading it correctly? > > Yes. Without the ugly normalization step in the middle could either > use twelve cases instead of four here or use inline alternatives, > e.g.: > > type T; > T *dst_ptr; > T *src_ptr; > T[] dst_arr; > T[] src_arr; > expression n; > @@ > ( > - memcpy(dst_ptr, src_ptr, (n) * \( sizeof(*(dst_ptr)) \| sizeof(*(src_ptr)) \| sizeof(T) \) ) > + COPY_ARRAY(dst_ptr, src_ptr, n) > | > - memcpy(dst_ptr, src_arr, (n) * \( sizeof(*(dst_ptr)) \| sizeof(*(src_arr)) \| sizeof(T) \) ) > + COPY_ARRAY(dst_ptr, src_arr, n) > | > - memcpy(dst_arr, src_ptr, (n) * \( sizeof(*(dst_arr)) \| sizeof(*(src_ptr)) \| sizeof(T) \) ) > + COPY_ARRAY(dst_arr, src_ptr, n) > | > - memcpy(dst_arr, src_arr, (n) * \( sizeof(*(dst_arr)) \| sizeof(*(src_arr)) \| sizeof(T) \) ) > + COPY_ARRAY(dst_arr, src_arr, n) > ) > > I seem to remember that rules like this missed some cases, but perhaps > that's no longer an issue with the latest Coccinelle version? Not a problem, it seems; at least Coccinelle 1.1.1 is still able to recreate the conversions from 45ccef87b3 (use COPY_ARRAY, 2016-09-25) and 921d49be86 (use COPY_ARRAY for copying arrays, 2019-06-15) with the patch below, which removes the normalization rules. It increases the processing time for array.cocci from 53s to 66s for me, though. Worth the increased precision and clarity? René --- contrib/coccinelle/array.cocci | 82 +++++++++++++++++----------------- 1 file changed, 40 insertions(+), 42 deletions(-) diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci index 9a4f00cb1b..aa75937950 100644 --- a/contrib/coccinelle/array.cocci +++ b/contrib/coccinelle/array.cocci @@ -1,60 +1,58 @@ @@ -expression dst, src, n, E; +type T; +T *dst_ptr; +T *src_ptr; +expression n; @@ - memcpy(dst, src, n * sizeof( -- E[...] -+ *(E) - )) +- memcpy(dst_ptr, src_ptr, (n) * \( sizeof(T) +- \| sizeof(*(dst_ptr)) +- \| sizeof(*(src_ptr)) +- \| sizeof(dst_ptr[...]) +- \| sizeof(src_ptr[...]) +- \) ) ++ COPY_ARRAY(dst_ptr, src_ptr, n) @@ type T; -T *ptr; -T[] arr; -expression E, n; +T *dst_ptr; +T[] src_arr; +expression n; @@ -( - memcpy(ptr, E, -- n * sizeof(*(ptr)) -+ n * sizeof(T) - ) -| - memcpy(arr, E, -- n * sizeof(*(arr)) -+ n * sizeof(T) - ) -| - memcpy(E, ptr, -- n * sizeof(*(ptr)) -+ n * sizeof(T) - ) -| - memcpy(E, arr, -- n * sizeof(*(arr)) -+ n * sizeof(T) - ) -) +- memcpy(dst_ptr, src_arr, (n) * \( sizeof(T) +- \| sizeof(*(dst_ptr)) +- \| sizeof(*(src_arr)) +- \| sizeof(dst_ptr[...]) +- \| sizeof(src_arr[...]) +- \) ) ++ COPY_ARRAY(dst_ptr, src_arr, n) @@ type T; -T *dst_ptr; +T[] dst_arr; T *src_ptr; +expression n; +@@ +- memcpy(dst_arr, src_ptr, (n) * \( sizeof(T) +- \| sizeof(*(dst_arr)) +- \| sizeof(*(src_ptr)) +- \| sizeof(dst_arr[...]) +- \| sizeof(src_ptr[...]) +- \) ) ++ COPY_ARRAY(dst_arr, src_ptr, n) + +@@ +type T; T[] dst_arr; T[] src_arr; expression n; @@ -( -- memcpy(dst_ptr, src_ptr, (n) * sizeof(T)) -+ COPY_ARRAY(dst_ptr, src_ptr, n) -| -- memcpy(dst_ptr, src_arr, (n) * sizeof(T)) -+ COPY_ARRAY(dst_ptr, src_arr, n) -| -- memcpy(dst_arr, src_ptr, (n) * sizeof(T)) -+ COPY_ARRAY(dst_arr, src_ptr, n) -| -- memcpy(dst_arr, src_arr, (n) * sizeof(T)) +- memcpy(dst_arr, src_arr, (n) * \( sizeof(T) +- \| sizeof(*(dst_arr)) +- \| sizeof(*(src_arr)) +- \| sizeof(dst_arr[...]) +- \| sizeof(src_arr[...]) +- \) ) + COPY_ARRAY(dst_arr, src_arr, n) -) @@ type T; -- 2.37.0
