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-rw-r--r--tools/perf/util/expr.y421
1 files changed, 242 insertions, 179 deletions
diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y
index 7d226241f1d7..635e562350c5 100644
--- a/tools/perf/util/expr.y
+++ b/tools/perf/util/expr.y
@@ -1,238 +1,301 @@
/* Simple expression parser */
%{
-#include "util.h"
+#define YYDEBUG 1
+#include <assert.h>
+#include <math.h>
+#include <stdlib.h>
#include "util/debug.h"
-#include <stdlib.h> // strtod()
#define IN_EXPR_Y 1
#include "expr.h"
-#include "smt.h"
-#include <assert.h>
-#include <string.h>
-
-#define MAXIDLEN 256
%}
%define api.pure full
%parse-param { double *final_val }
-%parse-param { struct parse_ctx *ctx }
-%parse-param { const char **pp }
-%lex-param { const char **pp }
+%parse-param { struct expr_parse_ctx *ctx }
+%parse-param { bool compute_ids }
+%parse-param {void *scanner}
+%lex-param {void* scanner}
%union {
- double num;
- char id[MAXIDLEN+1];
+ double num;
+ char *str;
+ struct ids {
+ /*
+ * When creating ids, holds the working set of event ids. NULL
+ * implies the set is empty.
+ */
+ struct hashmap *ids;
+ /*
+ * The metric value. When not creating ids this is the value
+ * read from a counter, a constant or some computed value. When
+ * creating ids the value is either a constant or BOTTOM. NAN is
+ * used as the special BOTTOM value, representing a "set of all
+ * values" case.
+ */
+ double val;
+ } ids;
}
-%token <num> NUMBER
-%token <id> ID
-%token MIN MAX IF ELSE SMT_ON
+%token ID NUMBER MIN MAX IF ELSE LITERAL D_RATIO SOURCE_COUNT EXPR_ERROR
%left MIN MAX IF
%left '|'
%left '^'
%left '&'
+%left '<' '>'
%left '-' '+'
%left '*' '/' '%'
%left NEG NOT
-%type <num> expr if_expr
+%type <num> NUMBER LITERAL
+%type <str> ID
+%destructor { free ($$); } <str>
+%type <ids> expr if_expr
+%destructor { ids__free($$.ids); } <ids>
%{
-static int expr__lex(YYSTYPE *res, const char **pp);
-
-static void expr__error(double *final_val __maybe_unused,
- struct parse_ctx *ctx __maybe_unused,
- const char **pp __maybe_unused,
+static void expr_error(double *final_val __maybe_unused,
+ struct expr_parse_ctx *ctx __maybe_unused,
+ bool compute_ids __maybe_unused,
+ void *scanner,
const char *s)
{
pr_debug("%s\n", s);
}
-static int lookup_id(struct parse_ctx *ctx, char *id, double *val)
+/*
+ * During compute ids, the special "bottom" value uses NAN to represent the set
+ * of all values. NAN is selected as it isn't a useful constant value.
+ */
+#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 = {
+ .val = BOTTOM,
+ .ids = ids__union(ids1.ids, ids2.ids),
+ };
+ return result;
+}
+
+static struct ids handle_id(struct expr_parse_ctx *ctx, char *id,
+ bool compute_ids, bool source_count)
{
- int i;
+ struct ids result;
+
+ if (!compute_ids) {
+ /*
+ * Compute the event's value from ID. If the ID isn't known then
+ * it isn't used to compute the formula so set to NAN.
+ */
+ struct expr_id_data *data;
- for (i = 0; i < ctx->num_ids; i++) {
- if (!strcasecmp(ctx->ids[i].name, id)) {
- *val = ctx->ids[i].val;
- return 0;
+ result.val = NAN;
+ if (expr__resolve_id(ctx, id, &data) == 0) {
+ result.val = source_count
+ ? expr_id_data__source_count(data)
+ : expr_id_data__value(data);
+ }
+ result.ids = NULL;
+ free(id);
+ } else {
+ /*
+ * Set the value to BOTTOM to show that any value is possible
+ * when the event is computed. Create a set of just the ID.
+ */
+ result.val = BOTTOM;
+ result.ids = ids__new();
+ if (!result.ids || ids__insert(result.ids, id)) {
+ pr_err("Error creating IDs for '%s'", id);
+ free(id);
}
}
- return -1;
+ 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 || (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 { \
+ RESULT = union_expr(LHS, RHS); \
+ }
-all_expr: if_expr { *final_val = $1; }
- ;
-
-if_expr:
- expr IF expr ELSE expr { $$ = $3 ? $1 : $5; }
- | expr
- ;
-
-expr: NUMBER
- | ID { if (lookup_id(ctx, $1, &$$) < 0) {
- pr_debug("%s not found\n", $1);
- YYABORT;
- }
- }
- | expr '|' expr { $$ = (long)$1 | (long)$3; }
- | expr '&' expr { $$ = (long)$1 & (long)$3; }
- | expr '^' expr { $$ = (long)$1 ^ (long)$3; }
- | expr '+' expr { $$ = $1 + $3; }
- | expr '-' expr { $$ = $1 - $3; }
- | expr '*' expr { $$ = $1 * $3; }
- | expr '/' expr { if ($3 == 0) YYABORT; $$ = $1 / $3; }
- | expr '%' expr { if ((long)$3 == 0) YYABORT; $$ = (long)$1 % (long)$3; }
- | '-' expr %prec NEG { $$ = -$2; }
- | '(' if_expr ')' { $$ = $2; }
- | MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; }
- | MAX '(' expr ',' expr ')' { $$ = $3 > $5 ? $3 : $5; }
- | SMT_ON { $$ = smt_on() > 0; }
- ;
+#define BINARY_OP(RESULT, OP, LHS, RHS) \
+ if (!compute_ids || (is_const(LHS.val) && is_const(RHS.val))) { \
+ assert(LHS.ids == NULL); \
+ assert(RHS.ids == NULL); \
+ RESULT.val = LHS.val OP RHS.val; \
+ RESULT.ids = NULL; \
+ } else { \
+ RESULT = union_expr(LHS, RHS); \
+ }
+%}
%%
-static int expr__symbol(YYSTYPE *res, const char *p, const char **pp)
+start: if_expr
{
- char *dst = res->id;
- const char *s = p;
+ if (compute_ids)
+ ctx->ids = ids__union($1.ids, ctx->ids);
- if (*p == '#')
- *dst++ = *p++;
+ if (final_val)
+ *final_val = $1.val;
+}
+;
- while (isalnum(*p) || *p == '_' || *p == '.' || *p == ':' || *p == '@' || *p == '\\') {
- if (p - s >= MAXIDLEN)
- return -1;
+if_expr: expr IF expr ELSE if_expr
+{
+ if (fpclassify($3.val) == FP_ZERO) {
/*
- * Allow @ instead of / to be able to specify pmu/event/ without
- * conflicts with normal division.
+ * The IF expression evaluated to 0 so treat as false, take the
+ * ELSE and discard everything else.
*/
- if (*p == '@')
- *dst++ = '/';
- else if (*p == '\\')
- *dst++ = *++p;
- else
- *dst++ = *p;
- p++;
- }
- *dst = 0;
- *pp = p;
- dst = res->id;
- switch (dst[0]) {
- case 'm':
- if (!strcmp(dst, "min"))
- return MIN;
- if (!strcmp(dst, "max"))
- return MAX;
- break;
- case 'i':
- if (!strcmp(dst, "if"))
- return IF;
- break;
- case 'e':
- if (!strcmp(dst, "else"))
- return ELSE;
- break;
- case '#':
- if (!strcasecmp(dst, "#smt_on"))
- return SMT_ON;
- break;
+ $$.val = $5.val;
+ $$.ids = $5.ids;
+ ids__free($1.ids);
+ ids__free($3.ids);
+ } else if (!compute_ids || is_const($3.val)) {
+ /*
+ * If ids aren't computed then treat the expression as true. If
+ * ids are being computed and the IF expr is a non-zero
+ * constant, then also evaluate the true case.
+ */
+ $$.val = $1.val;
+ $$.ids = $1.ids;
+ ids__free($3.ids);
+ ids__free($5.ids);
+ } else if ($1.val == $5.val) {
+ /*
+ * LHS == RHS, so both are an identical constant. No need to
+ * evaluate any events.
+ */
+ $$.val = $1.val;
+ $$.ids = NULL;
+ ids__free($1.ids);
+ ids__free($3.ids);
+ ids__free($5.ids);
+ } else {
+ /*
+ * Value is either the LHS or RHS and we need the IF expression
+ * to compute it.
+ */
+ $$ = union_expr($1, union_expr($3, $5));
}
- return ID;
}
+| expr
+;
-static int expr__lex(YYSTYPE *res, const char **pp)
+expr: NUMBER
{
- int tok;
- const char *s;
- const char *p = *pp;
-
- while (isspace(*p))
- p++;
- s = p;
- switch (*p++) {
- case '#':
- case 'a' ... 'z':
- case 'A' ... 'Z':
- return expr__symbol(res, p - 1, pp);
- case '0' ... '9': case '.':
- res->num = strtod(s, (char **)&p);
- tok = NUMBER;
- break;
- default:
- tok = *s;
- break;
+ $$.val = $1;
+ $$.ids = NULL;
+}
+| ID { $$ = handle_id(ctx, $1, compute_ids, /*source_count=*/false); }
+| SOURCE_COUNT '(' ID ')' { $$ = handle_id(ctx, $3, compute_ids, /*source_count=*/true); }
+| expr '|' expr { BINARY_LONG_OP($$, |, $1, $3); }
+| expr '&' expr { BINARY_LONG_OP($$, &, $1, $3); }
+| expr '^' expr { BINARY_LONG_OP($$, ^, $1, $3); }
+| expr '<' expr { BINARY_OP($$, <, $1, $3); }
+| expr '>' expr { BINARY_OP($$, >, $1, $3); }
+| expr '+' expr { BINARY_OP($$, +, $1, $3); }
+| expr '-' expr { BINARY_OP($$, -, $1, $3); }
+| expr '*' expr { BINARY_OP($$, *, $1, $3); }
+| expr '/' expr
+{
+ 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. */
+ $$ = union_expr($1, $3);
}
- *pp = p;
- return tok;
}
-
-/* Caller must make sure id is allocated */
-void expr__add_id(struct parse_ctx *ctx, const char *name, double val)
+| expr '%' expr
{
- int idx;
- assert(ctx->num_ids < MAX_PARSE_ID);
- idx = ctx->num_ids++;
- ctx->ids[idx].name = name;
- ctx->ids[idx].val = val;
+ if (fpclassify($3.val) == FP_ZERO) {
+ pr_debug("division by zero\n");
+ YYABORT;
+ } else if (!compute_ids || (is_const($1.val) && is_const($3.val))) {
+ assert($1.ids == NULL);
+ assert($3.ids == NULL);
+ $$.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);
+ }
}
-
-void expr__ctx_init(struct parse_ctx *ctx)
+| D_RATIO '(' expr ',' expr ')'
+{
+ 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;
+ } else {
+ /* LHS and/or RHS need computing from event IDs so union. */
+ $$ = union_expr($3, $5);
+ }
+}
+| '-' expr %prec NEG
{
- ctx->num_ids = 0;
+ $$.val = -$2.val;
+ $$.ids = $2.ids;
}
-
-static bool already_seen(const char *val, const char *one, const char **other,
- int num_other)
+| '(' if_expr ')'
{
- int i;
-
- if (one && !strcasecmp(one, val))
- return true;
- for (i = 0; i < num_other; i++)
- if (!strcasecmp(other[i], val))
- return true;
- return false;
+ $$ = $2;
}
-
-int expr__find_other(const char *p, const char *one, const char ***other,
- int *num_otherp)
+| MIN '(' expr ',' expr ')'
{
- const char *orig = p;
- int err = -1;
- int num_other;
-
- *other = malloc((EXPR_MAX_OTHER + 1) * sizeof(char *));
- if (!*other)
- return -1;
-
- num_other = 0;
- for (;;) {
- YYSTYPE val;
- int tok = expr__lex(&val, &p);
- if (tok == 0) {
- err = 0;
- break;
- }
- if (tok == ID && !already_seen(val.id, one, *other, num_other)) {
- if (num_other >= EXPR_MAX_OTHER - 1) {
- pr_debug("Too many extra events in %s\n", orig);
- break;
- }
- (*other)[num_other] = strdup(val.id);
- if (!(*other)[num_other])
- return -1;
- num_other++;
- }
+ if (!compute_ids) {
+ $$.val = $3.val < $5.val ? $3.val : $5.val;
+ $$.ids = NULL;
+ } else {
+ $$ = union_expr($3, $5);
}
- (*other)[num_other] = NULL;
- *num_otherp = num_other;
- if (err) {
- *num_otherp = 0;
- free(*other);
- *other = NULL;
+}
+| MAX '(' expr ',' expr ')'
+{
+ if (!compute_ids) {
+ $$.val = $3.val > $5.val ? $3.val : $5.val;
+ $$.ids = NULL;
+ } else {
+ $$ = union_expr($3, $5);
}
- return err;
}
+| LITERAL
+{
+ $$.val = $1;
+ $$.ids = NULL;
+}
+;
+
+%%
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.