On Tue, Jun 7, 2011 at 1:50 PM, H.J. Lu <hjl.to...@gmail.com> wrote: > On Wed, Jun 1, 2011 at 2:23 AM, Ira Rosen <ira.ro...@linaro.org> wrote: >> Hi, >> >> The vectorizer expects widening multiplication pattern to be: >> >> type a_t, b_t; >> TYPE a_T, b_T, prod_T; >> >> a_T = (TYPE) a_t; >> b_T = (TYPE) b_t; >> prod_T = a_T * b_T; >> >> where type 'TYPE' is double the size of type 'type'. This works fine >> when the types are signed. For the unsigned types the code looks like: >> >> unsigned type a_t, b_t; >> unsigned TYPE u_prod_T; >> TYPE a_T, b_T, prod_T; >> >> a_T = (TYPE) a_t; >> b_T = (TYPE) b_t; >> prod_T = a_T * b_T; >> u_prod_T = (unsigned TYPE) prod_T; >> >> i.e., the multiplication is done on signed, followed by a cast to unsigned. >> This patch adds a support of such patterns and generates >> WIDEN_MULT_EXPR for the unsigned type. >> >> Another unsupported case is multiplication by a constant (e.g., b_T is >> a constant). This patch checks that the constant fits the smaller type >> 'type' and recognizes such cases as widening multiplication. >> >> Bootstrapped and tested on powerpc64-suse-linux. Tested the >> vectorization testsuite on arm-linux-gnueabi. >> I'll commit the patch shortly if there are no comments/objections. >> >> Ira >> >> ChangeLog: >> >> * tree-vectorizer.h (vect_recog_func_ptr): Make last argument to be >> a pointer. >> * tree-vect-patterns.c (vect_recog_widen_sum_pattern, >> vect_recog_widen_mult_pattern, vect_recog_dot_prod_pattern, >> vect_recog_pow_pattern): Likewise. >> (vect_pattern_recog_1): Remove declaration. >> (widened_name_p): Remove declaration. Add new argument to specify >> whether to check that both types are either signed or unsigned. >> (vect_recog_widen_mult_pattern): Update documentation. Handle >> unsigned patterns and multiplication by constants. >> (vect_pattern_recog_1): Update vect_recog_func references. Use >> statement information from the statement returned from pattern >> detection functions. >> (vect_pattern_recog): Update vect_recog_func reference. >> * tree-vect-stmts.c (vectorizable_type_promotion): For widening >> multiplication by a constant use the type of the other operand. >> > . > > This caused: > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49318 >
This also caused: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49478 -- H.J.
