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
the function can never be called. So remove as dead code. Tidy up the
EM_NONE cases for arm in dwarf-regs.c.

Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/arch/arm/util/Build        |  2 -
 tools/perf/arch/arm/util/dwarf-regs.c | 61 ---------------------------
 tools/perf/util/dwarf-regs.c          |  4 +-
 tools/perf/util/include/dwarf-regs.h  |  2 +-
 4 files changed, 3 insertions(+), 66 deletions(-)
 delete mode 100644 tools/perf/arch/arm/util/dwarf-regs.c

diff --git a/tools/perf/arch/arm/util/Build b/tools/perf/arch/arm/util/Build
index e06fea1ea8ff..f7a8b37d1c68 100644
--- a/tools/perf/arch/arm/util/Build
+++ b/tools/perf/arch/arm/util/Build
@@ -1,7 +1,5 @@
 perf-util-y += perf_regs.o
 
-perf-util-$(CONFIG_LIBDW) += dwarf-regs.o
-
 perf-util-$(CONFIG_LOCAL_LIBUNWIND)    += unwind-libunwind.o
 perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
 
diff --git a/tools/perf/arch/arm/util/dwarf-regs.c b/tools/perf/arch/arm/util/dwarf-regs.c
deleted file mode 100644
index fc5f71c91802..000000000000
--- a/tools/perf/arch/arm/util/dwarf-regs.c
+++ /dev/null
@@ -1,61 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Mapping of DWARF debug register numbers into register names.
- *
- * Copyright (C) 2010 Will Deacon, ARM Ltd.
- */
-
-#include <stddef.h>
-#include <linux/stringify.h>
-#include <dwarf-regs.h>
-
-struct pt_regs_dwarfnum {
-	const char *name;
-	unsigned int dwarfnum;
-};
-
-#define REG_DWARFNUM_NAME(r, num) {.name = r, .dwarfnum = num}
-#define GPR_DWARFNUM_NAME(num) \
-	{.name = __stringify(%r##num), .dwarfnum = num}
-#define REG_DWARFNUM_END {.name = NULL, .dwarfnum = 0}
-
-/*
- * Reference:
- * http://infocenter.arm.com/help/topic/com.arm.doc.ihi0040a/IHI0040A_aadwarf.pdf
- */
-static const struct pt_regs_dwarfnum regdwarfnum_table[] = {
-	GPR_DWARFNUM_NAME(0),
-	GPR_DWARFNUM_NAME(1),
-	GPR_DWARFNUM_NAME(2),
-	GPR_DWARFNUM_NAME(3),
-	GPR_DWARFNUM_NAME(4),
-	GPR_DWARFNUM_NAME(5),
-	GPR_DWARFNUM_NAME(6),
-	GPR_DWARFNUM_NAME(7),
-	GPR_DWARFNUM_NAME(8),
-	GPR_DWARFNUM_NAME(9),
-	GPR_DWARFNUM_NAME(10),
-	REG_DWARFNUM_NAME("%fp", 11),
-	REG_DWARFNUM_NAME("%ip", 12),
-	REG_DWARFNUM_NAME("%sp", 13),
-	REG_DWARFNUM_NAME("%lr", 14),
-	REG_DWARFNUM_NAME("%pc", 15),
-	REG_DWARFNUM_END,
-};
-
-/**
- * get_arch_regstr() - lookup register name from it's DWARF register number
- * @n:	the DWARF register number
- *
- * get_arch_regstr() returns the name of the register in struct
- * regdwarfnum_table from it's DWARF register number. If the register is not
- * found in the table, this returns NULL;
- */
-const char *get_arch_regstr(unsigned int n)
-{
-	const struct pt_regs_dwarfnum *roff;
-	for (roff = regdwarfnum_table; roff->name != NULL; roff++)
-		if (roff->dwarfnum == n)
-			return roff->name;
-	return NULL;
-}
diff --git a/tools/perf/util/dwarf-regs.c b/tools/perf/util/dwarf-regs.c
index 18e916c8e993..fd21f9e90e40 100644
--- a/tools/perf/util/dwarf-regs.c
+++ b/tools/perf/util/dwarf-regs.c
@@ -32,14 +32,14 @@
 const char *get_dwarf_regstr(unsigned int n, unsigned int machine,
 			     unsigned int flags __maybe_unused)
 {
-#if EM_HOST == EM_X86_64 || EM_HOST == EM_386 || EM_HOST == EM_AARCH64
+#if EM_HOST == EM_X86_64 || EM_HOST == EM_386 || EM_HOST == EM_AARCH64 || EM_HOST == EM_ARM
 	if (machine == EM_NONE) {
 		/* Generic arch - use host arch */
 		machine = EM_HOST;
 	}
 #endif
 	switch (machine) {
-#if EM_HOST != EM_X86_64 && EM_HOST != EM_386 && EM_HOST != EM_AARCH64
+#if EM_HOST != EM_X86_64 && EM_HOST != EM_386 && EM_HOST != EM_AARCH64 && EM_HOST != EM_ARM
 	case EM_NONE:	/* Generic arch - use host arch */
 		return get_arch_regstr(n);
 #endif
diff --git a/tools/perf/util/include/dwarf-regs.h b/tools/perf/util/include/dwarf-regs.h
index f976528fdfd6..3652f9d98fe4 100644
--- a/tools/perf/util/include/dwarf-regs.h
+++ b/tools/perf/util/include/dwarf-regs.h
@@ -89,7 +89,7 @@
 #define DWARF_REG_FB  0xd3affb /* random number */
 
 #ifdef HAVE_LIBDW_SUPPORT
-#if !defined(__x86_64__) && !defined(__i386__) && !defined(__aarch64__)
+#if !defined(__x86_64__) && !defined(__i386__) && !defined(__aarch64__) && !defined(__arm__)
 const char *get_arch_regstr(unsigned int n);
 #endif
 
-- 
2.47.0.277.g8800431eea-goog