test(callgrind): smoke-test VG_(find_DebugInfo) attribution

Add a tiny C program with hot_fn in .text plus warm_fn/cold_fn in
orphan executable sections (warm_code/cold_code) that sit in the
same R-E LOAD but outside text_avma..text_avma+text_size. The
.vgtest compares the resolved ob= basenames against an expected
list, verifying callgrind attributes events to the test binary
even when execution leaves .text.

Author: not-matthias

callgrind/tests/Makefile.am

@@ -10,6 +10,7 @@ EXTRA_DIST = \
 	ann1.post.exp ann1.stderr.exp ann1.vgtest \
 	ann2.post.exp ann2.stderr.exp ann2.vgtest \
 	clreq.vgtest clreq.stderr.exp \
+	find_debuginfo.vgtest find_debuginfo.stderr.exp find_debuginfo.post.exp \
 	runtime_obj_skip_py.vgtest runtime_obj_skip_py.stderr.exp runtime_obj_skip_py.post.exp \
 	runtime_obj_skip_py.py runtime_obj_skip_py_shim.c \
 	bug497723.stderr.exp bug497723.post.exp bug497723.vgtest \
@@ -30,7 +31,7 @@ EXTRA_DIST = \
 	inline-crossfile.vgtest inline-crossfile.stderr.exp inline-crossfile.stdout.exp inline-crossfile.post.exp \
 	inline-crossfile-helper1.h inline-crossfile-helper2.h filter_inline
 
-check_PROGRAMS = clreq simwork threads inline-samefile inline-crossfile
+check_PROGRAMS = clreq find_debuginfo simwork threads inline-samefile inline-crossfile
 
 AM_CFLAGS   += $(AM_FLAG_M3264_PRI)
 AM_CXXFLAGS += $(AM_FLAG_M3264_PRI)

callgrind/tests/find_debuginfo.c

@@ -0,0 +1,26 @@
+/* Exercise VG_(find_DebugInfo) including the filename fallback for
+   executable code that lives outside the section named ".text".
+
+   Functions placed in orphan sections "warm_code" and "cold_code" end up
+   in their own ELF sections (PROGBITS, AX) inside the same R-E LOAD as
+   .text but *outside* di->text_avma/text_size. Calls into them force
+   VG_(find_DebugInfo) past the primary text-range check and into the
+   am_find_nsegment + filename match path added in commit 938e424b1. */
+
+static int hot_fn(int x) { return x + 1; }
+
+__attribute__((noinline, section("warm_code")))
+static int warm_fn(int x) { return x * 3 + 7; }
+
+__attribute__((noinline, section("cold_code")))
+static int cold_fn(int x) { return x ^ 0x5a; }
+
+int main(void)
+{
+   int y = 0;
+   for (int i = 0; i < 1000; i++)
+      y = hot_fn(y);
+   y = warm_fn(y);
+   y = cold_fn(y);
+   return y & 0xff;
+}

callgrind/tests/find_debuginfo.post.exp

@@ -0,0 +1,3 @@
+find_debuginfo
+ld-linux-x86-64.so.2
+libc.so.6

callgrind/tests/find_debuginfo.stderr.exp

@@ -0,0 +1,6 @@
+
+
+Events    : Ir
+Collected :
+
+I   refs:

callgrind/tests/find_debuginfo.vgtest

@@ -0,0 +1,4 @@
+prog: find_debuginfo
+vgopts: --compress-strings=no --callgrind-out-file=callgrind.out.find_debuginfo
+post: sh -c 'sed -n "s|^ob=.*/||p" callgrind.out.find_debuginfo | grep -v "^vgpreload" | sort -u'
+cleanup: rm -f callgrind.out.find_debuginfo