[PATCH 1/3] perf expr: Add parsing support for multiple expressions

[Jiri Olsa <jolsa@kernel.org>]

Adding support to parse metric difinitions in following form:

  NAME = EXPRESSION ;
  NAME = EXPRESSION ;
  ...

The parsed NAME and EXPRESSION will be used in following
changes to feed the metric code with definitions from
custom file.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/tests/expr.c | 13 +++++++++++++
 tools/perf/util/expr.c  |  6 ++++++
 tools/perf/util/expr.h  | 19 +++++++++++++++++--
 tools/perf/util/expr.l  | 12 ++++++++++++
 tools/perf/util/expr.y  | 13 ++++++++++++-
 5 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
index ea10fc4412c4..b220e316048a 100644
--- a/tools/perf/tests/expr.c
+++ b/tools/perf/tests/expr.c
@@ -63,5 +63,18 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
 		zfree(&other[i]);
 	free((void *)other);
 
+	expr__ctx_init(&ctx);
+	ret = expr__parse_custom(&ctx, "IPC=INSTRUCTIONS / CYCLES; CPI=CYCLES / INSTRUCTIONS;");
+	TEST_ASSERT_VAL("parse custom failed", ret == 0);
+	TEST_ASSERT_VAL("parse custom count", ctx.num_custom == 2);
+	TEST_ASSERT_VAL("parse custom name", !strcmp(ctx.custom[0].name, "IPC"));
+	TEST_ASSERT_VAL("parse custom name", !strcmp(ctx.custom[1].name, "CPI"));
+	TEST_ASSERT_VAL("parse custom expr", !strcmp(ctx.custom[0].expr, "INSTRUCTIONS / CYCLES"));
+	TEST_ASSERT_VAL("parse custom expr", !strcmp(ctx.custom[1].expr, "CYCLES / INSTRUCTIONS"));
+
+	for (i = 0; i < ctx.num_custom; i++) {
+		zfree(&ctx.custom[i].name);
+		zfree(&ctx.custom[i].expr);
+	}
 	return 0;
 }
diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c
index c3382d58cf40..805fbf6bffc8 100644
--- a/tools/perf/util/expr.c
+++ b/tools/perf/util/expr.c
@@ -23,6 +23,7 @@ void expr__add_id(struct expr_parse_ctx *ctx, const char *name, double val)
 void expr__ctx_init(struct expr_parse_ctx *ctx)
 {
 	ctx->num_ids = 0;
+	ctx->num_custom = 0;
 }
 
 static int
@@ -59,6 +60,11 @@ int expr__parse(double *final_val, struct expr_parse_ctx *ctx, const char *expr)
 	return __expr__parse(final_val, ctx, expr, EXPR_PARSE) ? -1 : 0;
 }
 
+int expr__parse_custom(struct expr_parse_ctx *ctx, const char *expr)
+{
+	return __expr__parse(NULL, ctx, expr, EXPR_CUSTOM);
+}
+
 static bool
 already_seen(const char *val, const char *one, const char **other,
 	     int num_other)
diff --git a/tools/perf/util/expr.h b/tools/perf/util/expr.h
index 0938ad166ece..4bbd24f9aaaa 100644
--- a/tools/perf/util/expr.h
+++ b/tools/perf/util/expr.h
@@ -4,15 +4,29 @@
 
 #define EXPR_MAX_OTHER 20
 #define MAX_PARSE_ID EXPR_MAX_OTHER
+#define EXPR_MAX 20
 
 struct expr_parse_id {
 	const char *name;
 	double val;
 };
 
+struct expr_parse_custom {
+	const char *name;
+	const char *expr;
+};
+
 struct expr_parse_ctx {
-	int num_ids;
-	struct expr_parse_id ids[MAX_PARSE_ID];
+	union {
+		struct {
+			int			 num_ids;
+			struct expr_parse_id	 ids[MAX_PARSE_ID];
+		};
+		struct {
+			int			 num_custom;
+			struct expr_parse_custom custom[EXPR_MAX];
+		};
+	};
 };
 
 struct expr_scanner_ctx {
@@ -22,6 +36,7 @@ struct expr_scanner_ctx {
 void expr__ctx_init(struct expr_parse_ctx *ctx);
 void expr__add_id(struct expr_parse_ctx *ctx, const char *id, double val);
 int expr__parse(double *final_val, struct expr_parse_ctx *ctx, const char *expr);
+int expr__parse_custom(struct expr_parse_ctx *ctx, const char *expr);
 int expr__find_other(const char *expr, const char *one, const char ***other,
 		int *num_other);
 
diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
index 2582c2464938..5561c360cd27 100644
--- a/tools/perf/util/expr.l
+++ b/tools/perf/util/expr.l
@@ -68,12 +68,15 @@ static int str(yyscan_t scanner, int token)
 }
 %}
 
+%x custom
+
 number		[0-9]+
 
 sch		[-,=]
 spec		\\{sch}
 sym		[0-9a-zA-Z_\.:@]+
 symbol		{spec}*{sym}*{spec}*{sym}*
+all		[^;]+
 
 %%
 	struct expr_scanner_ctx *sctx = expr_get_extra(yyscanner);
@@ -87,6 +90,12 @@ symbol		{spec}*{sym}*{spec}*{sym}*
 		}
 	}
 
+<custom>{
+
+{all}		{ BEGIN(INITIAL); return str(yyscanner, ALL); }
+
+}
+
 max		{ return MAX; }
 min		{ return MIN; }
 if		{ return IF; }
@@ -105,6 +114,9 @@ else		{ return ELSE; }
 "("		{ return '('; }
 ")"		{ return ')'; }
 ","		{ return ','; }
+";"		{ return ';'; }
+"="		{ BEGIN(custom); return '='; }
+\n		{ }
 .		{ }
 %%
 
diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y
index cd17486c1c5d..a853974e7871 100644
--- a/tools/perf/util/expr.y
+++ b/tools/perf/util/expr.y
@@ -24,9 +24,10 @@
 	char	*str;
 }
 
-%token EXPR_PARSE EXPR_OTHER EXPR_ERROR
+%token EXPR_PARSE EXPR_OTHER EXPR_CUSTOM EXPR_ERROR
 %token <num> NUMBER
 %token <str> ID
+%token <str> ALL
 %token MIN MAX IF ELSE SMT_ON
 %left MIN MAX IF
 %left '|'
@@ -66,6 +67,16 @@ start:
 EXPR_PARSE all_expr
 |
 EXPR_OTHER all_other
+|
+EXPR_CUSTOM all_custom
+
+all_custom: all_custom ID '=' ALL ';'
+{
+	ctx->custom[ctx->num_custom].name = $2;
+	ctx->custom[ctx->num_custom].expr = $4;
+	ctx->num_custom++;
+}
+|
 
 all_other: all_other other
 |
-- 
2.25.3