[PATCH v8 8/8] perf test: Add metric test for eliminating events

[Ian Rogers <irogers@google.com>]

Add test that ensures we remove events based on #smt_on, or if
evaluating the event has no impact on the output.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/expr.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
index 1c881bea7fca..5cab5960b257 100644
--- a/tools/perf/tests/expr.c
+++ b/tools/perf/tests/expr.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "util/debug.h"
 #include "util/expr.h"
+#include "util/smt.h"
 #include "tests.h"
 #include <stdlib.h>
 #include <string.h>
@@ -132,6 +133,22 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
 	TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, "EVENT2,param=3/",
 						    (void **)&val_ptr));
 
+	/* Only EVENT1 or EVENT2 need be measured depending on the value of smt_on. */
+	expr__ctx_clear(ctx);
+	TEST_ASSERT_VAL("find ids",
+			expr__find_ids("EVENT1 if #smt_on else EVENT2",
+				NULL, ctx, 0) == 0);
+	TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1);
+	TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids,
+						  smt_on() ? "EVENT1" : "EVENT2",
+						  (void **)&val_ptr));
+
+	/* The expression is a constant 1.0 without needing to evaluate EVENT1. */
+	expr__ctx_clear(ctx);
+	TEST_ASSERT_VAL("find ids",
+			expr__find_ids("1.0 if EVENT1 > 100.0 else 1.0",
+				NULL, ctx, 0) == 0);
+	TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 0);
 	expr__ctx_free(ctx);
 
 	return 0;
-- 
2.33.0.464.g1972c5931b-goog