Re: [V4 06/16] tools/perf: Update parameters for reg extract functions to use raw instruction on powerpc

Namhyung Kim
2024-06-25T06:00:36Z

On Fri, Jun 14, 2024 at 10:56:21PM +0530, Athira Rajeev wrote:
> Use the raw instruction code and macros to identify memory instructions,
> extract register fields and also offset. The implementation addresses
> the D-form, X-form, DS-form instructions. Two main functions are added.
> New parse function "load_store__parse" as instruction ops parser for
> memory instructions. Unlink other parser (like mov__parse), this parser
> fills in the "multi_regs" field for source/target and new added "mem_ref"
> field. No other fields are set because, here there is no need to parse the
> disassembled code and arch specific macros will take care of extracting
> offset and regs which is easier and will be precise.
>
> In powerpc, all instructions with a primary opcode from 32 to 63
> are memory instructions. Update "ins__find" function to have "raw_insn"
> also as a parameter. Don't use the "extract_reg_offset", instead use
> newly added function "get_arch_regs" which will set these fields: reg1,
> reg2, offset depending of where it is source or target ops.
>
> Update "parse" callback for "struct ins_ops" to also pass "struct
> disasm_line" as argument. This is needed in parse functions where opcode
> is used to determine whether to set multi_regs.

Can you please split "ins__find" change and "parse" change into separate
commits?

>
> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
> ---
> tools/perf/arch/arm64/annotate/instructions.c | 3 +-
> .../arch/loongarch/annotate/instructions.c | 6 +-
> .../perf/arch/powerpc/annotate/instructions.c | 16 ++++
> tools/perf/arch/powerpc/util/dwarf-regs.c | 44 +++++++++++
> tools/perf/arch/s390/annotate/instructions.c | 5 +-
> tools/perf/util/annotate.c | 25 ++++++-
> tools/perf/util/disasm.c | 73 ++++++++++++++++---
> tools/perf/util/disasm.h | 6 +-
> tools/perf/util/include/dwarf-regs.h | 3 +
> 9 files changed, 159 insertions(+), 22 deletions(-)
>
> diff --git a/tools/perf/arch/arm64/annotate/instructions.c b/tools/perf/arch/arm64/annotate/instructions.c
> index 4af0c3a0f86e..f86d9f4798bd 100644
> --- a/tools/perf/arch/arm64/annotate/instructions.c
> +++ b/tools/perf/arch/arm64/annotate/instructions.c
> @@ -11,7 +11,8 @@ struct arm64_annotate {
>
> static int arm64_mov__parse(struct arch *arch __maybe_unused,
> struct ins_operands *ops,
> - struct map_symbol *ms __maybe_unused)
> + struct map_symbol *ms __maybe_unused,
> + struct disasm_line *dl __maybe_unused)
> {
> char *s = strchr(ops->raw, ','), *target, *endptr;
>
> diff --git a/tools/perf/arch/loongarch/annotate/instructions.c b/tools/perf/arch/loongarch/annotate/instructions.c
> index 21cc7e4149f7..ab43b1ab51e3 100644
> --- a/tools/perf/arch/loongarch/annotate/instructions.c
> +++ b/tools/perf/arch/loongarch/annotate/instructions.c
> @@ -5,7 +5,8 @@
> * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> */
>
> -static int loongarch_call__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms)
> +static int loongarch_call__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms,
> + struct disasm_line *dl __maybe_unused)
> {
> char *c, *endptr, *tok, *name;
> struct map *map = ms->map;
> @@ -51,7 +52,8 @@ static struct ins_ops loongarch_call_ops = {
> .scnprintf = call__scnprintf,
> };
>
> -static int loongarch_jump__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms)
> +static int loongarch_jump__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms,
> + struct disasm_line *dl __maybe_unused)
> {
> struct map *map = ms->map;
> struct symbol *sym = ms->sym;
> diff --git a/tools/perf/arch/powerpc/annotate/instructions.c b/tools/perf/arch/powerpc/annotate/instructions.c
> index d57fd023ef9c..10fea5e5cf4c 100644
> --- a/tools/perf/arch/powerpc/annotate/instructions.c
> +++ b/tools/perf/arch/powerpc/annotate/instructions.c
> @@ -49,6 +49,22 @@ static struct ins_ops *powerpc__associate_instruction_ops(struct arch *arch, con
> return ops;
> }
>
> +#define PPC_OP(op) (((op) >> 26) & 0x3F)
> +
> +static struct ins_ops *check_ppc_insn(int raw_insn)

It'd be nice to use 'u32' instead of 'int' for raw_insn if you want to
do some bit operations.

> +{
> + int opcode = PPC_OP(raw_insn);
> +
> + /*
> + * Instructions with opcode 32 to 63 are memory
> + * instructions in powerpc
> + */
> + if ((opcode & 0x20))
> + return &load_store_ops;
> +
> + return NULL;
> +}
> +
> static int powerpc__annotate_init(struct arch *arch, char *cpuid __maybe_unused)
> {
> if (!arch->initialized) {
> diff --git a/tools/perf/arch/powerpc/util/dwarf-regs.c b/tools/perf/arch/powerpc/util/dwarf-regs.c
> index 430623ca5612..e01729f3c0b3 100644
> --- a/tools/perf/arch/powerpc/util/dwarf-regs.c
> +++ b/tools/perf/arch/powerpc/util/dwarf-regs.c
> @@ -107,3 +107,47 @@ int regs_query_register_offset(const char *name)
> #define PPC_DS(DS) ((DS) & 0xfffc)
> #define OP_LD 58
> #define OP_STD 62
> +
> +static int get_source_reg(unsigned int raw_insn)
> +{
> + return PPC_RA(raw_insn);

Ditto, and others too.

> +}
> +
> +static int get_target_reg(unsigned int raw_insn)
> +{
> + return PPC_RT(raw_insn);
> +}
> +
> +static int get_offset_opcode(int raw_insn)
> +{
> + int opcode = PPC_OP(raw_insn);
> +
> + /* DS- form */
> + if ((opcode == OP_LD) || (opcode == OP_STD))
> + return PPC_DS(raw_insn);
> + else
> + return PPC_D(raw_insn);
> +}
> +
> +/*
> + * Fills the required fields for op_loc depending on if it
> + * is a source or target.
> + * D form: ins RT,D(RA) -> src_reg1 = RA, offset = D, dst_reg1 = RT
> + * DS form: ins RT,DS(RA) -> src_reg1 = RA, offset = DS, dst_reg1 = RT
> + * X form: ins RT,RA,RB -> src_reg1 = RA, src_reg2 = RB, dst_reg1 = RT
> + */
> +void get_arch_regs(int raw_insn, int is_source,
> + struct annotated_op_loc *op_loc)
> +{
> + if (is_source)
> + op_loc->reg1 = get_source_reg(raw_insn);
> + else
> + op_loc->reg1 = get_target_reg(raw_insn);
> +
> + if (op_loc->multi_regs)
> + op_loc->reg2 = PPC_RB(raw_insn);
> +
> + /* TODO: Implement offset handling for X Form */
> + if ((op_loc->mem_ref) && (PPC_OP(raw_insn) != 31))
> + op_loc->offset = get_offset_opcode(raw_insn);
> +}
> diff --git a/tools/perf/arch/s390/annotate/instructions.c b/tools/perf/arch/s390/annotate/instructions.c
> index da5aa3e1f04c..eeac25cca699 100644
> --- a/tools/perf/arch/s390/annotate/instructions.c
> +++ b/tools/perf/arch/s390/annotate/instructions.c
> @@ -2,7 +2,7 @@
> #include <linux/compiler.h>
>
> static int s390_call__parse(struct arch *arch, struct ins_operands *ops,
> - struct map_symbol *ms)
> + struct map_symbol *ms, struct disasm_line *dl __maybe_unused)
> {
> char *endptr, *tok, *name;
> struct map *map = ms->map;
> @@ -52,7 +52,8 @@ static struct ins_ops s390_call_ops = {
>
> static int s390_mov__parse(struct arch *arch __maybe_unused,
> struct ins_operands *ops,
> - struct map_symbol *ms __maybe_unused)
> + struct map_symbol *ms __maybe_unused,
> + struct disasm_line *dl __maybe_unused)
> {
> char *s = strchr(ops->raw, ','), *target, *endptr;
>
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 1451caf25e77..bfa6420dc4b9 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -2079,6 +2079,12 @@ static int extract_reg_offset(struct arch *arch, const char *str,
> return 0;
> }
>
> +__weak void get_arch_regs(int raw_insn __maybe_unused, int is_source __maybe_unused,
> + struct annotated_op_loc *op_loc __maybe_unused)

I'd like to avoid adding weak functions if possible. It's supposed to
be powerpc only, maybe you can add get_powerpc_regs() in the arch
directory and add a dummy static inline somewhere under #ifndef.

> +{
> + return;
> +}
> +
> /**
> * annotate_get_insn_location - Get location of instruction
> * @arch: the architecture info
> @@ -2123,20 +2129,33 @@ int annotate_get_insn_location(struct arch *arch, struct disasm_line *dl,
> for_each_insn_op_loc(loc, i, op_loc) {
> const char *insn_str = ops->source.raw;
> bool multi_regs = ops->source.multi_regs;
> + bool mem_ref = ops->source.mem_ref;
>
> if (i == INSN_OP_TARGET) {
> insn_str = ops->target.raw;
> multi_regs = ops->target.multi_regs;
> + mem_ref = ops->target.mem_ref;
> }
>
> /* Invalidate the register by default */
> op_loc->reg1 = -1;
> op_loc->reg2 = -1;
>
> - if (insn_str == NULL)
> - continue;
> + if (insn_str == NULL) {
> + if (!arch__is(arch, "powerpc"))
> + continue;
> + }
>
> - if (strchr(insn_str, arch->objdump.memory_ref_char)) {
> + /*
> + * For powerpc, call get_arch_regs function which extracts the
> + * required fields for op_loc, ie reg1, reg2, offset from the
> + * raw instruction.
> + */
> + if (arch__is(arch, "powerpc")) {
> + op_loc->mem_ref = mem_ref;
> + op_loc->multi_regs = multi_regs;
> + get_arch_regs(dl->raw.raw_insn, !i, op_loc);
> + } else if (strchr(insn_str, arch->objdump.memory_ref_char)) {
> op_loc->mem_ref = true;
> op_loc->multi_regs = multi_regs;
> extract_reg_offset(arch, insn_str, op_loc);
> diff --git a/tools/perf/util/disasm.c b/tools/perf/util/disasm.c
> index 1e8568738b38..8428df0b9c17 100644
> --- a/tools/perf/util/disasm.c
> +++ b/tools/perf/util/disasm.c
> @@ -37,6 +37,7 @@ static struct ins_ops mov_ops;
> static struct ins_ops nop_ops;
> static struct ins_ops lock_ops;
> static struct ins_ops ret_ops;
> +static struct ins_ops load_store_ops;
>
> static int jump__scnprintf(struct ins *ins, char *bf, size_t size,
> struct ins_operands *ops, int max_ins_name);
> @@ -254,7 +255,8 @@ bool ins__is_fused(struct arch *arch, const char *ins1, const char *ins2)
> return arch->ins_is_fused(arch, ins1, ins2);
> }
>
> -static int call__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms)
> +static int call__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms,
> + struct disasm_line *dl __maybe_unused)
> {
> char *endptr, *tok, *name;
> struct map *map = ms->map;
> @@ -349,7 +351,8 @@ static inline const char *validate_comma(const char *c, struct ins_operands *ops
> return c;
> }
>
> -static int jump__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms)
> +static int jump__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms,
> + struct disasm_line *dl __maybe_unused)
> {
> struct map *map = ms->map;
> struct symbol *sym = ms->sym;
> @@ -508,7 +511,8 @@ static int comment__symbol(char *raw, char *comment, u64 *addrp, char **namep)
> return 0;
> }
>
> -static int lock__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms)
> +static int lock__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms,
> + struct disasm_line *dl __maybe_unused)
> {
> ops->locked.ops = zalloc(sizeof(*ops->locked.ops));
> if (ops->locked.ops == NULL)
> @@ -517,13 +521,13 @@ static int lock__parse(struct arch *arch, struct ins_operands *ops, struct map_s
> if (disasm_line__parse(ops->raw, &ops->locked.ins.name, &ops->locked.ops->raw) < 0)
> goto out_free_ops;
>
> - ops->locked.ins.ops = ins__find(arch, ops->locked.ins.name);
> + ops->locked.ins.ops = ins__find(arch, ops->locked.ins.name, 0);
>
> if (ops->locked.ins.ops == NULL)
> goto out_free_ops;
>
> if (ops->locked.ins.ops->parse &&
> - ops->locked.ins.ops->parse(arch, ops->locked.ops, ms) < 0)
> + ops->locked.ins.ops->parse(arch, ops->locked.ops, ms, NULL) < 0)
> goto out_free_ops;
>
> return 0;
> @@ -594,7 +598,8 @@ static bool check_multi_regs(struct arch *arch, const char *op)
> return count > 1;
> }
>
> -static int mov__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms __maybe_unused)
> +static int mov__parse(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms __maybe_unused,
> + struct disasm_line *dl __maybe_unused)
> {
> char *s = strchr(ops->raw, ','), *target, *comment, prev;
>
> @@ -672,7 +677,39 @@ static struct ins_ops mov_ops = {
> .scnprintf = mov__scnprintf,
> };
>
> -static int dec__parse(struct arch *arch __maybe_unused, struct ins_operands *ops, struct map_symbol *ms __maybe_unused)
> +static int load_store__scnprintf(struct ins *ins, char *bf, size_t size,
> + struct ins_operands *ops, int max_ins_name)
> +{
> + return scnprintf(bf, size, "%-*s %s", max_ins_name, ins->name,
> + ops->raw);
> +}
> +
> +/*
> + * Sets the fields: multi_regs and "mem_ref".
> + * "mem_ref" is set for ops->source which is later used to
> + * fill the objdump->memory_ref-char field. This ops is currently
> + * used by powerpc and since binary instruction code is used to
> + * extract opcode, regs and offset, no other parsing is needed here
> + */
> +static int load_store__parse(struct arch *arch __maybe_unused, struct ins_operands *ops,
> + struct map_symbol *ms __maybe_unused, struct disasm_line *dl __maybe_unused)
> +{
> + ops->source.mem_ref = true;
> + ops->source.multi_regs = false;
> +
> + ops->target.mem_ref = false;
> + ops->target.multi_regs = false;
> +
> + return 0;
> +}
> +
> +static struct ins_ops load_store_ops = {
> + .parse = load_store__parse,
> + .scnprintf = load_store__scnprintf,
> +};
> +
> +static int dec__parse(struct arch *arch __maybe_unused, struct ins_operands *ops, struct map_symbol *ms __maybe_unused,
> + struct disasm_line *dl __maybe_unused)
> {
> char *target, *comment, *s, prev;
>
> @@ -762,11 +799,23 @@ static void ins__sort(struct arch *arch)
> qsort(arch->instructions, nmemb, sizeof(struct ins), ins__cmp);
> }
>
> -static struct ins_ops *__ins__find(struct arch *arch, const char *name)
> +static struct ins_ops *__ins__find(struct arch *arch, const char *name, int raw_insn)
> {
> struct ins *ins;
> const int nmemb = arch->nr_instructions;
>
> + if (arch__is(arch, "powerpc")) {
> + /*
> + * For powerpc, identify the instruction ops
> + * from the opcode using raw_insn.
> + */
> + struct ins_ops *ops;
> +
> + ops = check_ppc_insn(raw_insn);
> + if (ops)
> + return ops;
> + }
> +
> if (!arch->sorted_instructions) {
> ins__sort(arch);
> arch->sorted_instructions = true;
> @@ -796,9 +845,9 @@ static struct ins_ops *__ins__find(struct arch *arch, const char *name)
> return ins ? ins->ops : NULL;
> }
>
> -struct ins_ops *ins__find(struct arch *arch, const char *name)
> +struct ins_ops *ins__find(struct arch *arch, const char *name, int raw_insn)
> {
> - struct ins_ops *ops = __ins__find(arch, name);
> + struct ins_ops *ops = __ins__find(arch, name, raw_insn);
>
> if (!ops && arch->associate_instruction_ops)
> ops = arch->associate_instruction_ops(arch, name);
> @@ -808,12 +857,12 @@ struct ins_ops *ins__find(struct arch *arch, const char *name)
>
> static void disasm_line__init_ins(struct disasm_line *dl, struct arch *arch, struct map_symbol *ms)
> {
> - dl->ins.ops = ins__find(arch, dl->ins.name);
> + dl->ins.ops = ins__find(arch, dl->ins.name, dl->raw.raw_insn);
>
> if (!dl->ins.ops)
> return;
>
> - if (dl->ins.ops->parse && dl->ins.ops->parse(arch, &dl->ops, ms) < 0)
> + if (dl->ins.ops->parse && dl->ins.ops->parse(arch, &dl->ops, ms, dl) < 0)
> dl->ins.ops = NULL;
> }
>
> diff --git a/tools/perf/util/disasm.h b/tools/perf/util/disasm.h
> index 718177fa4775..6b6ec23e4f6f 100644
> --- a/tools/perf/util/disasm.h
> +++ b/tools/perf/util/disasm.h
> @@ -57,6 +57,7 @@ struct ins_operands {
> bool offset_avail;
> bool outside;
> bool multi_regs;
> + bool mem_ref;
> } target;
> union {
> struct {
> @@ -64,6 +65,7 @@ struct ins_operands {
> char *name;
> u64 addr;
> bool multi_regs;
> + bool mem_ref;
> } source;
> struct {
> struct ins ins;
> @@ -78,7 +80,7 @@ struct ins_operands {
>
> struct ins_ops {
> void (*free)(struct ins_operands *ops);
> - int (*parse)(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms);
> + int (*parse)(struct arch *arch, struct ins_operands *ops, struct map_symbol *ms, struct disasm_line *dl);

The line is too long, please break.

Thanks,
Namhyung

> int (*scnprintf)(struct ins *ins, char *bf, size_t size,
> struct ins_operands *ops, int max_ins_name);
> };
> @@ -97,7 +99,7 @@ struct annotate_args {
> struct arch *arch__find(const char *name);
> bool arch__is(struct arch *arch, const char *name);
>
> -struct ins_ops *ins__find(struct arch *arch, const char *name);
> +struct ins_ops *ins__find(struct arch *arch, const char *name, int raw_insn);
> int ins__scnprintf(struct ins *ins, char *bf, size_t size,
> struct ins_operands *ops, int max_ins_name);
>
> diff --git a/tools/perf/util/include/dwarf-regs.h b/tools/perf/util/include/dwarf-regs.h
> index 01fb25a1150a..7ea39362ecaf 100644
> --- a/tools/perf/util/include/dwarf-regs.h
> +++ b/tools/perf/util/include/dwarf-regs.h
> @@ -1,6 +1,7 @@
> /* SPDX-License-Identifier: GPL-2.0 */
> #ifndef _PERF_DWARF_REGS_H_
> #define _PERF_DWARF_REGS_H_
> +#include "annotate.h"
>
> #define DWARF_REG_PC 0xd3af9c /* random number */
> #define DWARF_REG_FB 0xd3affb /* random number */
> @@ -31,6 +32,8 @@ static inline int get_dwarf_regnum(const char *name __maybe_unused,
> }
> #endif
>
> +void get_arch_regs(int raw_insn, int is_source, struct annotated_op_loc *op_loc);
> +
> #ifdef HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET
> /*
> * Arch should support fetching the offset of a register in pt_regs
> --
> 2.43.0
>