[PATCH v8 03/17] perf capstone: Determine architecture from e_machine

[Ian Rogers <irogers@google.com>]

Avoid the use of arch string that is imprecise and use the
e_machine. Do more e_machine to capstone machine translations adding
MIPS and RISCV. Remove unnecessary maybe_unused annotations.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/capstone.c | 115 +++++++++++++++++++++++++------------
 1 file changed, 79 insertions(+), 36 deletions(-)

diff --git a/tools/perf/util/capstone.c b/tools/perf/util/capstone.c
index 25cf6e15ec27..e6226b751c36 100644
--- a/tools/perf/util/capstone.c
+++ b/tools/perf/util/capstone.c
@@ -16,6 +16,7 @@
 #include <fcntl.h>
 #include <inttypes.h>
 #include <string.h>
+#include <elf.h>
 
 #include <capstone/capstone.h>
 
@@ -137,37 +138,74 @@ static enum cs_err perf_cs_close(csh *handle)
 #endif
 }
 
-static int capstone_init(struct machine *machine, csh *cs_handle, bool is64,
-			 bool disassembler_style)
+static bool e_machine_to_capstone(uint16_t e_machine, bool is64,
+				  enum cs_arch *arch, enum cs_mode *mode)
+{
+        switch (e_machine) {
+        case EM_X86_64:
+		*arch = CS_ARCH_X86;
+		*mode = CS_MODE_64;
+		return true;
+        case EM_386:
+		*arch = CS_ARCH_X86;
+		*mode = CS_MODE_32;
+		return true;
+        case EM_AARCH64:
+		*arch = CS_ARCH_ARM64;
+		*mode = CS_MODE_ARM;
+		return true;
+        case EM_ARM:
+		*arch = CS_ARCH_ARM;
+		*mode = CS_MODE_ARM | CS_MODE_V8;
+		return true;
+        case EM_S390:
+		*arch = CS_ARCH_SYSZ;
+		*mode = CS_MODE_BIG_ENDIAN;
+		return true;
+        case EM_MIPS:
+		*arch = CS_ARCH_MIPS;
+		*mode = is64 ? CS_MODE_MIPS64 : CS_MODE_MIPS32;
+		*mode |= CS_MODE_BIG_ENDIAN;
+		return true;
+        case EM_PPC:
+		*arch = CS_ARCH_PPC;
+		*mode = CS_MODE_BIG_ENDIAN | CS_MODE_32;
+		return true;
+        case EM_PPC64:
+		*arch = CS_ARCH_PPC;
+		*mode = CS_MODE_BIG_ENDIAN | CS_MODE_64;
+		return true;
+        case EM_SPARC:
+		*arch = CS_ARCH_SPARC;
+		*mode = CS_MODE_BIG_ENDIAN | CS_MODE_32;
+		return true;
+        case EM_SPARCV9:
+		*arch = CS_ARCH_SPARC;
+		*mode = CS_MODE_BIG_ENDIAN | CS_MODE_V9 | CS_MODE_64;
+		return true;
+        case EM_RISCV:
+		*arch = CS_ARCH_RISCV;
+		*mode = is64 ? CS_MODE_RISCV64 : CS_MODE_RISCV32;
+		return true;
+        default:
+		return false;
+        }
+}
+
+static int capstone_init(uint16_t e_machine, csh *cs_handle, bool is64, bool disassembler_style)
 {
 	enum cs_arch arch;
 	enum cs_mode mode;
 
-	if (machine__is(machine, "x86_64") && is64) {
-		arch = CS_ARCH_X86;
-		mode = CS_MODE_64;
-	} else if (machine__normalized_is(machine, "x86")) {
-		arch = CS_ARCH_X86;
-		mode = CS_MODE_32;
-	} else if (machine__normalized_is(machine, "arm64")) {
-		arch = CS_ARCH_ARM64;
-		mode = CS_MODE_ARM;
-	} else if (machine__normalized_is(machine, "arm")) {
-		arch = CS_ARCH_ARM;
-		mode = CS_MODE_ARM + CS_MODE_V8;
-	} else if (machine__normalized_is(machine, "s390")) {
-		arch = CS_ARCH_SYSZ;
-		mode = CS_MODE_BIG_ENDIAN;
-	} else {
+	if (!e_machine_to_capstone(e_machine, is64, &arch, &mode))
 		return -1;
-	}
 
 	if (perf_cs_open(arch, mode, cs_handle) != CS_ERR_OK) {
 		pr_warning_once("cs_open failed\n");
 		return -1;
 	}
 
-	if (machine__normalized_is(machine, "x86")) {
+	if (arch == CS_ARCH_X86) {
 		/*
 		 * In case of using capstone_init while symbol__disassemble
 		 * setting CS_OPT_SYNTAX_ATT depends if disassembler_style opts
@@ -212,28 +250,31 @@ static size_t print_insn_x86(struct thread *thread, u8 cpumode, struct cs_insn *
 }
 
 
-ssize_t capstone__fprintf_insn_asm(struct machine *machine __maybe_unused,
-				   struct thread *thread __maybe_unused,
-				   u8 cpumode __maybe_unused, bool is64bit __maybe_unused,
-				   const uint8_t *code __maybe_unused,
-				   size_t code_size __maybe_unused,
-				   uint64_t ip __maybe_unused, int *lenp __maybe_unused,
-				   int print_opts __maybe_unused, FILE *fp __maybe_unused)
+ssize_t capstone__fprintf_insn_asm(struct machine *machine,
+				   struct thread *thread,
+				   u8 cpumode,
+				   bool is64bit,
+				   const uint8_t *code,
+				   size_t code_size,
+				   uint64_t ip, int *lenp,
+				   int print_opts,
+				   FILE *fp)
 {
 	size_t printed;
 	struct cs_insn *insn;
 	csh cs_handle;
 	size_t count;
+	uint16_t e_machine = thread__e_machine(thread, machine, /*e_flags=*/NULL);
 	int ret;
 
 	/* TODO: Try to initiate capstone only once but need a proper place. */
-	ret = capstone_init(machine, &cs_handle, is64bit, true);
+	ret = capstone_init(e_machine, &cs_handle, is64bit, /*disassembler_style=*/true);
 	if (ret < 0)
 		return ret;
 
 	count = perf_cs_disasm(cs_handle, code, code_size, ip, 1, &insn);
 	if (count > 0) {
-		if (machine__normalized_is(machine, "x86"))
+		if (e_machine == EM_X86_64 || e_machine == EM_386)
 			printed = print_insn_x86(thread, cpumode, &insn[0], print_opts, fp);
 		else
 			printed = fprintf(fp, "%s %s", insn[0].mnemonic, insn[0].op_str);
@@ -322,9 +363,9 @@ static int find_file_offset(u64 start, u64 len, u64 pgoff, void *arg)
 	return 0;
 }
 
-int symbol__disassemble_capstone(const char *filename __maybe_unused,
-				 struct symbol *sym __maybe_unused,
-				 struct annotate_args *args __maybe_unused)
+int symbol__disassemble_capstone(const char *filename,
+				 struct symbol *sym,
+				 struct annotate_args *args)
 {
 	struct annotation *notes = symbol__annotation(sym);
 	struct map *map = args->ms->map;
@@ -344,6 +385,7 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused,
 	char disasm_buf[512];
 	struct disasm_line *dl;
 	bool disassembler_style = false;
+	uint16_t e_machine;
 
 	if (args->options->objdump_path)
 		return -1;
@@ -373,8 +415,8 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused,
 	    !strcmp(args->options->disassembler_style, "att"))
 		disassembler_style = true;
 
-	if (capstone_init(maps__machine(thread__maps(args->ms->thread)), &handle, is_64bit,
-			  disassembler_style) < 0)
+	e_machine = thread__e_machine(args->ms->thread, /*machine=*/NULL, /*e_flags=*/NULL);
+	if (capstone_init(e_machine, &handle, is_64bit, disassembler_style) < 0)
 		goto err;
 
 	needs_cs_close = true;
@@ -466,6 +508,7 @@ int symbol__disassemble_capstone_powerpc(const char *filename __maybe_unused,
 	struct disasm_line *dl;
 	u32 *line;
 	bool disassembler_style = false;
+	uint16_t e_machine;
 
 	if (args->options->objdump_path)
 		return -1;
@@ -484,8 +527,8 @@ int symbol__disassemble_capstone_powerpc(const char *filename __maybe_unused,
 	    !strcmp(args->options->disassembler_style, "att"))
 		disassembler_style = true;
 
-	if (capstone_init(maps__machine(thread__maps(args->ms->thread)), &handle, is_64bit,
-			  disassembler_style) < 0)
+	e_machine = thread__e_machine(args->ms->thread, /*machine=*/NULL, /*e_flags=*/NULL);
+	if (capstone_init(e_machine, &handle, is_64bit, disassembler_style) < 0)
 		goto err;
 
 	needs_cs_close = true;
-- 
2.54.0.545.g6539524ca2-goog