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| author | Eric Botcazou <ebotcazou@adacore.com> | 2015-02-06 11:17:46 +0000 |
|---|---|---|
| committer | Eric Botcazou <ebotcazou@gcc.gnu.org> | 2015-02-06 11:17:46 +0000 |
| commit | 9fb87eb0bb346faced57e1f7ea0f9d7f4b9dd472 (patch) | |
| tree | 4a6525f3942b6ce4873f4432f6de86d0e1892563 | |
| parent | 9f9ab303f713366fd57c338802735b86dcebf110 (diff) | |
| download | gcc-9fb87eb0bb346faced57e1f7ea0f9d7f4b9dd472.zip gcc-9fb87eb0bb346faced57e1f7ea0f9d7f4b9dd472.tar.gz gcc-9fb87eb0bb346faced57e1f7ea0f9d7f4b9dd472.tar.bz2 | |
re PR target/62631 (gcc.dg/tree-ssa/ivopts-lt-2.c FAILs)
PR target/62631
* tree-ssa-loop-ivopts.c (get_shiftadd_cost): Use the mininum of costs
of shift-add and (add + shift) operations. Rename local variable.
From-SVN: r220473
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/tree-ssa-loop-ivopts.c | 18 |
2 files changed, 17 insertions, 7 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4d84df7..7cf5049 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2015-02-06 Eric Botcazou <ebotcazou@adacore.com> + + PR target/62631 + * tree-ssa-loop-ivopts.c (get_shiftadd_cost): Use the mininum of costs + of shift-add and (add + shift) operations. Rename local variable. + 2015-02-05 Jeff Law <law@redhat.com> PR target/17306 diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c index bde68e7..a701636 100644 --- a/gcc/tree-ssa-loop-ivopts.c +++ b/gcc/tree-ssa-loop-ivopts.c @@ -3597,22 +3597,26 @@ get_shiftadd_cost (tree expr, machine_mode mode, comp_cost cost0, tree multop = TREE_OPERAND (mult, 0); int m = exact_log2 (int_cst_value (cst)); int maxm = MIN (BITS_PER_WORD, GET_MODE_BITSIZE (mode)); - int sa_cost; - bool equal_p = false; + int as_cost, sa_cost; + bool mult_in_op1; if (!(m >= 0 && m < maxm)) return false; - if (operand_equal_p (op1, mult, 0)) - equal_p = true; + mult_in_op1 = operand_equal_p (op1, mult, 0); + as_cost = add_cost (speed, mode) + shift_cost (speed, mode, m); + + /* If the target has a cheap shift-and-add or shift-and-sub instruction, + use that in preference to a shift insn followed by an add insn. */ sa_cost = (TREE_CODE (expr) != MINUS_EXPR ? shiftadd_cost (speed, mode, m) - : (equal_p + : (mult_in_op1 ? shiftsub1_cost (speed, mode, m) : shiftsub0_cost (speed, mode, m))); - res = new_cost (sa_cost, 0); - res = add_costs (res, equal_p ? cost0 : cost1); + + res = new_cost (MIN (as_cost, sa_cost), 0); + res = add_costs (res, mult_in_op1 ? cost0 : cost1); STRIP_NOPS (multop); if (!is_gimple_val (multop)) |