[PATCH 3/4] perf annotate: add powerpc support

[Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>]

From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>

Powerpc has long list of branch instructions and hardcoding them in table
appears to be error-prone. So, add new function to find instruction
instead of creating table.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
---
 tools/perf/util/annotate.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 36a5825..96c6610 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -476,6 +476,68 @@ static int ins__cmp(const void *a, const void *b)
 	return strcmp(ia->name, ib->name);
 }
 
+static struct ins *ins__find_powerpc(const char *name)
+{
+	int i;
+	struct ins *ins;
+
+	ins = zalloc(sizeof(struct ins));
+	if (!ins)
+		return NULL;
+
+	ins->name = strdup(name);
+	if (!ins->name)
+		return NULL;
+
+	if (name[0] == 'b') {
+		/* branch instructions */
+		ins->ops = &jump_ops;
+
+		/*
+		 * - Few start with 'b', but aren't branch instructions.
+		 * - Let's also ignore instructions involving 'ctr' and
+		 *   'tar' since target branch addresses for those can't
+		 *   be determined statically.
+		 */
+		if (!strncmp(name, "bcd", 3)   ||
+		    !strncmp(name, "brinc", 5) ||
+		    !strncmp(name, "bper", 4)  ||
+		    strstr(name, "ctr")        ||
+		    strstr(name, "tar"))
+			return NULL;
+
+		i = strlen(name) - 1;
+		if (i < 0)
+			return NULL;
+
+		/* ignore optional hints at the end of the instructions */
+		if (name[i] == '+' || name[i] == '-')
+			i--;
+
+		if (name[i] == 'l' || (name[i] == 'a' && name[i-1] == 'l')) {
+			/*
+			 * if the instruction ends up with 'l' or 'la', then
+			 * those are considered 'calls' since they update LR.
+			 * ... except for 'bnl' which is branch if not less than
+			 * and the absolute form of the same.
+			 */
+			if (strcmp(name, "bnl") && strcmp(name, "bnl+") &&
+			    strcmp(name, "bnl-") && strcmp(name, "bnla") &&
+			    strcmp(name, "bnla+") && strcmp(name, "bnla-"))
+				ins->ops = &call_ops;
+		}
+		if (name[i] == 'r' && name[i-1] == 'l')
+			/*
+			 * instructions ending with 'lr' are considered to be
+			 * return instructions
+			 */
+			ins->ops = &ret_ops;
+
+		return ins;
+	}
+	return NULL;
+}
+
 static void ins__sort(struct ins *instructions, int nmemb)
 {
 	qsort(instructions, nmemb, sizeof(struct ins), ins__cmp);
@@ -511,6 +573,8 @@ static struct ins *ins__find(const char *name, const char *norm_arch)
 	} else if (!strcmp(norm_arch, "arm")) {
 		instructions = instructions_arm;
 		nmemb = ARRAY_SIZE(instructions_arm);
+	} else if (!strcmp(norm_arch, "powerpc")) {
+		return ins__find_powerpc(name);
 	} else {
 		pr_err("perf annotate not supported by %s arch\n", norm_arch);
 		return NULL;
-- 
2.5.5