diff options
Diffstat (limited to 'tools/perf/util/expr.y')
| -rw-r--r-- | tools/perf/util/expr.y | 63 |
1 files changed, 45 insertions, 18 deletions
diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y index 6aeead54760a..5a295e385914 100644 --- a/tools/perf/util/expr.y +++ b/tools/perf/util/expr.y @@ -68,6 +68,12 @@ static void expr_error(double *final_val __maybe_unused, */ #define BOTTOM NAN +/* During computing ids, does val represent a constant (non-BOTTOM) value? */ +static bool is_const(double val) +{ + return isfinite(val); +} + static struct ids union_expr(struct ids ids1, struct ids ids2) { struct ids result = { @@ -77,8 +83,15 @@ static struct ids union_expr(struct ids ids1, struct ids ids2) return result; } +/* + * If we're not computing ids or $1 and $3 are constants, compute the new + * constant value using OP. Its invariant that there are no ids. If computing + * ids for non-constants union the set of IDs that must be computed. + */ #define BINARY_LONG_OP(RESULT, OP, LHS, RHS) \ - if (!compute_ids) { \ + if (!compute_ids || (is_const(LHS.val) && is_const(RHS.val))) { \ + assert(LHS.ids == NULL); \ + assert(RHS.ids == NULL); \ RESULT.val = (long)LHS.val OP (long)RHS.val; \ RESULT.ids = NULL; \ } else { \ @@ -86,7 +99,9 @@ static struct ids union_expr(struct ids ids1, struct ids ids2) } #define BINARY_OP(RESULT, OP, LHS, RHS) \ - if (!compute_ids) { \ + if (!compute_ids || (is_const(LHS.val) && is_const(RHS.val))) { \ + assert(LHS.ids == NULL); \ + assert(RHS.ids == NULL); \ RESULT.val = LHS.val OP RHS.val; \ RESULT.ids = NULL; \ } else { \ @@ -163,40 +178,52 @@ expr: NUMBER | expr '*' expr { BINARY_OP($$, *, $1, $3); } | expr '/' expr { - if (!compute_ids) { - if (fpclassify($3.val) == FP_ZERO) { - pr_debug("division by zero\n"); - YYABORT; - } + if (fpclassify($3.val) == FP_ZERO) { + pr_debug("division by zero\n"); + YYABORT; + } else if (!compute_ids || (is_const($1.val) && is_const($3.val))) { + assert($1.ids == NULL); + assert($3.ids == NULL); $$.val = $1.val / $3.val; $$.ids = NULL; } else { + /* LHS and/or RHS need computing from event IDs so union. */ $$ = union_expr($1, $3); } } | expr '%' expr { - if (!compute_ids) { - if (fpclassify($3.val) == FP_ZERO) { - pr_debug("division by zero\n"); - YYABORT; - } + if (fpclassify($3.val) == FP_ZERO) { + pr_debug("division by zero\n"); + YYABORT; + } else if (!compute_ids || (is_const($1.val) && is_const($3.val))) { + assert($1.ids == NULL); + assert($3.ids == NULL); $$.val = (long)$1.val % (long)$3.val; $$.ids = NULL; } else { + /* LHS and/or RHS need computing from event IDs so union. */ $$ = union_expr($1, $3); } } | D_RATIO '(' expr ',' expr ')' { - if (!compute_ids) { + if (fpclassify($5.val) == FP_ZERO) { + /* + * Division by constant zero always yields zero and no events + * are necessary. + */ + assert($5.ids == NULL); + $$.val = 0.0; + $$.ids = NULL; + ids__free($3.ids); + } else if (!compute_ids || (is_const($3.val) && is_const($5.val))) { + assert($3.ids == NULL); + assert($5.ids == NULL); + $$.val = $3.val / $5.val; $$.ids = NULL; - if (fpclassify($5.val) == FP_ZERO) { - $$.val = 0.0; - } else { - $$.val = $3.val / $5.val; - } } else { + /* LHS and/or RHS need computing from event IDs so union. */ $$ = union_expr($3, $5); } } |