perf annotate: Initial PowerPC support

Support the PowerPC architecture using the ins_ops association
method.

Committer notes:

Testing it with a perf.data file collected on a PowerPC machine and
cross-annotated on a x86_64 workstation, using the associated vmlinux
file:

$ perf report -i perf.data.f22vm.powerdev --vmlinux vmlinux.powerpc
.ktime_get vmlinux.powerpc
│ clrldi r9,r28,63
8.57 │ ┌──bne e0 <- TUI cursor positioned here
│54:│ lwsync
2.86 │ │ std r2,40(r1)
│ │ ld r9,144(r31)
│ │ ld r3,136(r31)
│ │ ld r30,184(r31)
│ │ ld r10,0(r9)
│ │ mtctr r10
│ │ ld r2,8(r9)
8.57 │ │→ bctrl
│ │ ld r2,40(r1)
│ │ ld r10,160(r31)
│ │ ld r5,152(r31)
│ │ lwz r7,168(r31)
│ │ ld r9,176(r31)
8.57 │ │ lwz r6,172(r31)
│ │ lwsync
2.86 │ │ lwz r8,128(r31)
│ │ cmpw cr7,r8,r28
2.86 │ │↑ bne 48
│ │ subf r10,r10,r3
│ │ mr r3,r29
│ │ and r10,r10,r5
2.86 │ │ mulld r10,r10,r7
│ │ add r9,r10,r9
│ │ srd r9,r9,r6
│ │ add r9,r9,r30
│ │ std r9,0(r29)
│ │ addi r1,r1,144
│ │ ld r0,16(r1)
│ │ ld r28,-32(r1)
│ │ ld r29,-24(r1)
│ │ ld r30,-16(r1)
│ │ mtlr r0
│ │ ld r31,-8(r1)
│ │← blr
5.71 │e0:└─→mr r1,r1
11.43 │ mr r2,r2
11.43 │ lwz r28,128(r31)
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$ perf report -i perf.data.f22vm.powerdev --header-only
# ========
# captured on: Thu Nov 24 12:40:38 2016
# hostname : pdev-f22-qemu
# os release : 4.4.10-200.fc22.ppc64
# perf version : 4.9.rc1.g6298ce
# arch : ppc64
# nrcpus online : 48
# nrcpus avail : 48
# cpudesc : POWER7 (architected), altivec supported
# cpuid : 74,513
# total memory : 4158976 kB
# cmdline : /home/ravi/Workspace/linux/tools/perf/perf record -a
# event : name = cycles:ppp, , size = 112, { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|CPU|PERIOD, disabled = 1, inherit = 1, mmap = 1, comm = 1, freq = 1, task = 1, precise_ip = 3, sample_id_all = 1, exclude_guest = 1, mmap2 = 1, comm_exec = 1
# HEADER_CPU_TOPOLOGY info available, use -I to display
# HEADER_NUMA_TOPOLOGY info available, use -I to display
# pmu mappings: cpu = 4, software = 1, tracepoint = 2, breakpoint = 5
# missing features: HEADER_TRACING_DATA HEADER_BRANCH_STACK HEADER_GROUP_DESC HEADER_AUXTRACE HEADER_STAT HEADER_CACHE
# ========
#
$

Signed-off-by: Ravi Bangoria <[e-mail]>
Signed-off-by: Naveen N. Rao <[e-mail]>
Tested-by: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Kim Phillips <[e-mail]>
Link: http://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/arch/powerpc/annotate/instructions.c

···
+static struct ins_ops *powerpc__associate_instruction_ops(struct arch *arch, const char *name)
+{
+	int i;
+	struct ins_ops *ops;
+
+	/*
+	 * - Interested only if instruction starts with 'b'.
+	 * - Few start with 'b', but aren't branch instructions.
+	 */
+	if (name[0] != 'b'             ||
+	    !strncmp(name, "bcd", 3)   ||
+	    !strncmp(name, "brinc", 5) ||
+	    !strncmp(name, "bper", 4))
+		return NULL;
+
+	ops = &jump_ops;
+
+	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-"))
+			ops = &call_ops;
+	}
+	if (name[i] == 'r' && name[i-1] == 'l')
+		/*
+		 * instructions ending with 'lr' are considered to be
+		 * return instructions
+		 */
+		ops = &ret_ops;
+
+	arch__associate_ins_ops(arch, name, ops);
+	return ops;
+}
+
+static int powerpc__annotate_init(struct arch *arch)
+{
+	if (!arch->initialized) {
+		arch->initialized = true;
+		arch->associate_instruction_ops = powerpc__associate_instruction_ops;
+		arch->objdump.comment_char      = '#';
+	}
+
+	return 0;
+}

tools/perf/util/annotate.c

···
 
 #include "arch/arm/annotate/instructions.c"
 #include "arch/x86/annotate/instructions.c"
+#include "arch/powerpc/annotate/instructions.c"
 
 static struct arch architectures[] = {
 	{
···
 		.objdump =  {
 			.comment_char = '#',
 		},
+	},
+	{
+		.name = "powerpc",
+		.init = powerpc__annotate_init,
 	},
 };