From 3a0c26edc3d2f39da3a91eb6eae404253e7ccbaa Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Tue, 12 Dec 2023 16:13:12 -0800 Subject: perf annotate: Add annotate_get_insn_location() The annotate_get_insn_location() is to get the detailed information of instruction locations like registers and offset. It has source and target operands locations in an array. Each operand can have a register and an offset. The offset is meaningful when mem_ref flag is set. Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Stephane Eranian Cc: linux-toolchains@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Link: https://lore.kernel.org/r/20231213001323.718046-7-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/annotate.c | 107 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) (limited to 'tools/perf/util/annotate.c') diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c index 27b2a9961cd5..7c597440dc2e 100644 --- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -31,6 +31,7 @@ #include "bpf-utils.h" #include "block-range.h" #include "string2.h" +#include "dwarf-regs.h" #include "util/event.h" #include "util/sharded_mutex.h" #include "arch/common.h" @@ -3518,3 +3519,109 @@ int annotate_check_args(void) } return 0; } + +/* + * Get register number and access offset from the given instruction. + * It assumes AT&T x86 asm format like OFFSET(REG). Maybe it needs + * to revisit the format when it handles different architecture. + * Fills @reg and @offset when return 0. + */ +static int extract_reg_offset(struct arch *arch, const char *str, + struct annotated_op_loc *op_loc) +{ + char *p; + char *regname; + + if (arch->objdump.register_char == 0) + return -1; + + /* + * It should start from offset, but it's possible to skip 0 + * in the asm. So 0(%rax) should be same as (%rax). + * + * However, it also start with a segment select register like + * %gs:0x18(%rbx). In that case it should skip the part. + */ + if (*str == arch->objdump.register_char) { + while (*str && !isdigit(*str) && + *str != arch->objdump.memory_ref_char) + str++; + } + + op_loc->offset = strtol(str, &p, 0); + + p = strchr(p, arch->objdump.register_char); + if (p == NULL) + return -1; + + regname = strdup(p); + if (regname == NULL) + return -1; + + op_loc->reg = get_dwarf_regnum(regname, 0); + free(regname); + return 0; +} + +/** + * annotate_get_insn_location - Get location of instruction + * @arch: the architecture info + * @dl: the target instruction + * @loc: a buffer to save the data + * + * Get detailed location info (register and offset) in the instruction. + * It needs both source and target operand and whether it accesses a + * memory location. The offset field is meaningful only when the + * corresponding mem flag is set. + * + * Some examples on x86: + * + * mov (%rax), %rcx # src_reg = rax, src_mem = 1, src_offset = 0 + * # dst_reg = rcx, dst_mem = 0 + * + * mov 0x18, %r8 # src_reg = -1, dst_reg = r8 + */ +int annotate_get_insn_location(struct arch *arch, struct disasm_line *dl, + struct annotated_insn_loc *loc) +{ + struct ins_operands *ops; + struct annotated_op_loc *op_loc; + int i; + + if (!strcmp(dl->ins.name, "lock")) + ops = dl->ops.locked.ops; + else + ops = &dl->ops; + + if (ops == NULL) + return -1; + + memset(loc, 0, sizeof(*loc)); + + for_each_insn_op_loc(loc, i, op_loc) { + const char *insn_str = ops->source.raw; + + if (i == INSN_OP_TARGET) + insn_str = ops->target.raw; + + /* Invalidate the register by default */ + op_loc->reg = -1; + + if (insn_str == NULL) + continue; + + if (strchr(insn_str, arch->objdump.memory_ref_char)) { + op_loc->mem_ref = true; + extract_reg_offset(arch, insn_str, op_loc); + } else { + char *s = strdup(insn_str); + + if (s) { + op_loc->reg = get_dwarf_regnum(s, 0); + free(s); + } + } + } + + return 0; +} -- cgit