diff options
| author | Marc Glisse <marc.glisse@inria.fr> | 2019-05-31 18:54:30 +0200 |
|---|---|---|
| committer | Marc Glisse <glisse@gcc.gnu.org> | 2019-05-31 16:54:30 +0000 |
| commit | 9cf60d3b0d793fbd3b97aa0163b44a5c0c4e9aa3 (patch) | |
| tree | 79fec5f3316ae1b6c21485ab9aae4b5626f85b66 /gcc/match.pd | |
| parent | f4fde1b378ad68fb2dec6719ed26c1b901488e03 (diff) | |
Simplify more EXACT_DIV_EXPR comparisons
2019-05-31 Marc Glisse <marc.glisse@inria.fr>
gcc/
* match.pd (X/[ex]D<Y/[ex]D): Handle negative denominator.
((size_t)(A /[ex] B) CMP C): New transformation.
gcc/testsuite/
* gcc.dg/tree-ssa/cmpexactdiv-3.c: New file.
* gcc.dg/tree-ssa/cmpexactdiv-4.c: New file.
* gcc.dg/Walloca-13.c: Xfail.
From-SVN: r271816
Diffstat (limited to 'gcc/match.pd')
| -rw-r--r-- | gcc/match.pd | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index e1fa75cf5a0..99ffb16c872 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -1497,7 +1497,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (simplify (cmp (exact_div @0 INTEGER_CST@2) (exact_div @1 @2)) (if (wi::gt_p (wi::to_wide (@2), 0, TYPE_SIGN (TREE_TYPE (@2)))) - (cmp @0 @1)))) + (cmp @0 @1) + (if (wi::lt_p (wi::to_wide (@2), 0, TYPE_SIGN (TREE_TYPE (@2)))) + (cmp @1 @0))))) /* X / C1 op C2 into a simple range test. */ (for cmp (simple_comparison) @@ -3633,6 +3635,33 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) != (cmp == LT_EXPR || cmp == LE_EXPR), type); } (cmp @0 { wide_int_to_tree (TREE_TYPE (@0), prod); })))))) +/* Fold (size_t)(A /[ex] B) CMP C to (size_t)A CMP (size_t)B * C or A CMP' 0. + + For small C (less than max/B), this is (size_t)A CMP (size_t)B * C. + For large C (more than min/B+2^size), this is also true, with the + multiplication computed modulo 2^size. + For intermediate C, this just tests the sign of A. */ +(for cmp (lt le gt ge) + cmp2 (ge ge lt lt) + (simplify + (cmp (convert (exact_div @0 INTEGER_CST@1)) INTEGER_CST@2) + (if (tree_nop_conversion_p (TREE_TYPE (@0), TREE_TYPE (@2)) + && TYPE_UNSIGNED (TREE_TYPE (@2)) && !TYPE_UNSIGNED (TREE_TYPE (@0)) + && wi::gt_p (wi::to_wide (@1), 0, TYPE_SIGN (TREE_TYPE (@1)))) + (with + { + tree utype = TREE_TYPE (@2); + wide_int denom = wi::to_wide (@1); + wide_int right = wi::to_wide (@2); + wide_int smax = wi::sdiv_trunc (wi::max_value (TREE_TYPE (@0)), denom); + wide_int smin = wi::sdiv_trunc (wi::min_value (TREE_TYPE (@0)), denom); + bool small = wi::leu_p (right, smax); + bool large = wi::geu_p (right, smin); + } + (if (small || large) + (cmp (convert:utype @0) (mult @2 (convert @1))) + (cmp2 @0 { build_zero_cst (TREE_TYPE (@0)); })))))) + /* Unordered tests if either argument is a NaN. */ (simplify (bit_ior (unordered @0 @0) (unordered @1 @1)) |