perf riscv: Remove dwarf-regs.c and add dwarf-regs-table.h

The file just provides the function get_arch_regstr, however, if in
the only caller get_dwarf_regstr EM_HOST is used for the EM_NONE case,
and the register table is provided in a header file, the function can
never be called. So remove as dead code. Tidy up the EM_NONE cases for
riscv in dwarf-regs.c.

Reviewed-by: Masami Hiramatsu (Google) <[e-mail]>
Signed-off-by: Ian Rogers <[e-mail]>
Acked-by: Palmer Dabbelt <[e-mail]>
Cc: Anup Patel <[e-mail]>
Cc: Yang Jihong <[e-mail]>
Cc: Palmer Dabbelt <[e-mail]>
Cc: David S. Miller <[e-mail]>
Cc: Albert Ou <[e-mail]>
Cc: Shenlin Liang <[e-mail]>
Cc: Nick Terrell <[e-mail]>
Cc: Guilherme Amadio <[e-mail]>
Cc: Steinar H. Gunderson <[e-mail]>
Cc: Changbin Du <[e-mail]>
Cc: Alexander Lobakin <[e-mail]>
Cc: Przemek Kitszel <[e-mail]>
Cc: Huacai Chen <[e-mail]>
Cc: Guo Ren <[e-mail]>
Cc: Masahiro Yamada <[e-mail]>
Cc: Will Deacon <[e-mail]>
Cc: James Clark <[e-mail]>
Cc: Mike Leach <[e-mail]>
Cc: Chen Pei <[e-mail]>
Cc: Leo Yan <[e-mail]>
Cc: Oliver Upton <[e-mail]>
Cc: Aditya Gupta <[e-mail]>
Cc: Kajol Jain <[e-mail]>
Cc: Athira Rajeev <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: Bibo Mao <[e-mail]>
Cc: John Garry <[e-mail]>
Cc: Atish Patra <[e-mail]>
Cc: Dima Kogan <[e-mail]>
Cc: Paul Walmsley <[e-mail]>
Cc: Dr. David Alan Gilbert <[e-mail]>
Cc: [e-mail]
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Namhyung Kim <[e-mail]>

tools/perf/arch/riscv/util/Build

···
 perf-util-y += header.o
 
 perf-util-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
-perf-util-$(CONFIG_LIBDW) += dwarf-regs.o
 perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o

tools/perf/arch/riscv/util/dwarf-regs.c tools/perf/arch/riscv/include/dwarf-regs-table.h

···
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd.
- * Mapping of DWARF debug register numbers into register names.
- */
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifdef DEFINE_DWARF_REGSTR_TABLE
+/* This is included in perf/util/dwarf-regs.c */
 
-#include <stddef.h>
-#include <errno.h> /* for EINVAL */
-#include <string.h> /* for strcmp */
-#include <dwarf-regs.h>
+#define REG_DWARFNUM_NAME(reg, idx)	[idx] = "%" #reg
 
-struct regs_dwarfnum {
-	const char *name;
-	unsigned int dwarfnum;
-};
-
-#define REG_DWARFNUM_NAME(r, num) {.name = r, .dwarfnum = num}
-#define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0}
-
-struct regs_dwarfnum riscv_dwarf_regs_table[] = {
+static const char * const riscv_regstr_tbl[] = {
 	REG_DWARFNUM_NAME("%zero", 0),
 	REG_DWARFNUM_NAME("%ra", 1),
 	REG_DWARFNUM_NAME("%sp", 2),
···
 	REG_DWARFNUM_NAME("%t4", 29),
 	REG_DWARFNUM_NAME("%t5", 30),
 	REG_DWARFNUM_NAME("%t6", 31),
-	REG_DWARFNUM_END,
 };
 
-#define RISCV_MAX_REGS ((sizeof(riscv_dwarf_regs_table) / \
-		 sizeof(riscv_dwarf_regs_table[0])) - 1)
-
-const char *get_arch_regstr(unsigned int n)
-{
-	return (n < RISCV_MAX_REGS) ? riscv_dwarf_regs_table[n].name : NULL;
-}
+#endif

tools/perf/util/dwarf-regs.c

···
 #include "../arch/arm64/include/dwarf-regs-table.h"
 #include "../arch/sh/include/dwarf-regs-table.h"
 #include "../arch/powerpc/include/dwarf-regs-table.h"
+#include "../arch/riscv/include/dwarf-regs-table.h"
 #include "../arch/s390/include/dwarf-regs-table.h"
 #include "../arch/sparc/include/dwarf-regs-table.h"
 #include "../arch/xtensa/include/dwarf-regs-table.h"
···
 {
 #if EM_HOST == EM_X86_64 || EM_HOST == EM_386 || EM_HOST == EM_AARCH64 || EM_HOST == EM_ARM \
     || EM_HOST == EM_CSKY || EM_HOST == EM_LOONGARCH || EM_HOST == EM_MIPS || EM_HOST == EM_PPC \
-    || EM_HOST == EM_PPC64
+    || EM_HOST == EM_PPC64 || EM_HOST == EM_RISCV
 	if (machine == EM_NONE) {
 		/* Generic arch - use host arch */
 		machine = EM_HOST;
···
 	switch (machine) {
 #if EM_HOST != EM_X86_64 && EM_HOST != EM_386 && EM_HOST != EM_AARCH64 && EM_HOST != EM_ARM \
     && EM_HOST != EM_CSKY && EM_HOST != EM_LOONGARCH && EM_HOST != EM_MIPS && EM_HOST != EM_PPC \
-    && EM_HOST != EM_PPC64
+    && EM_HOST != EM_PPC64 && EM_HOST != EM_RISCV
 	case EM_NONE:	/* Generic arch - use host arch */
 		return get_arch_regstr(n);
 #endif
···
 	case EM_PPC:
 	case EM_PPC64:
 		return __get_dwarf_regstr(powerpc_regstr_tbl, n);
+	case EM_RISCV:
+		return __get_dwarf_regstr(riscv_regstr_tbl, n);
 	case EM_SPARC:
 	case EM_SPARCV9:
 		return __get_dwarf_regstr(sparc_regstr_tbl, n);

tools/perf/util/include/dwarf-regs.h

···
 #ifdef HAVE_LIBDW_SUPPORT
 #if !defined(__x86_64__) && !defined(__i386__) && !defined(__aarch64__) && !defined(__arm__) \
     && !defined(__loongarch__) && !defined(__mips__) && !defined(__powerpc__) \
-    && !defined(__powerpc64__)
+    && !defined(__powerpc64__) && !defined(__riscv__)
 const char *get_arch_regstr(unsigned int n);
 #endif