objtool: Convert insn type to enum

This makes it easier to add new instruction types.  Also it's hopefully
more robust since the compiler should warn about out-of-range enums.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/0740e96af0d40e54cfd6a07bf09db0fbd10793cd.1563413318.git.jpoimboe@redhat.com

4 files changed, 20 insertions, 26 deletions

diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h
index 580e344db3dd..50448c0c4bca 100644
--- a/tools/objtool/arch.h
+++ b/tools/objtool/arch.h
@@ -11,22 +11,23 @@
 #include "elf.h"
 #include "cfi.h"
 
-#define INSN_JUMP_CONDITIONAL   1
-#define INSN_JUMP_UNCONDITIONAL 2
-#define INSN_JUMP_DYNAMIC       3
-#define INSN_CALL               4
-#define INSN_CALL_DYNAMIC       5
-#define INSN_RETURN             6
-#define INSN_CONTEXT_SWITCH     7
-#define INSN_STACK              8
-#define INSN_BUG                9
-#define INSN_NOP                10
-#define INSN_STAC               11
-#define INSN_CLAC               12
-#define INSN_STD                13
-#define INSN_CLD                14
-#define INSN_OTHER              15
-#define INSN_LAST               INSN_OTHER
+enum insn_type {
+        INSN_JUMP_CONDITIONAL,
+        INSN_JUMP_UNCONDITIONAL,
+        INSN_JUMP_DYNAMIC,
+        INSN_CALL,
+        INSN_CALL_DYNAMIC,
+        INSN_RETURN,
+        INSN_CONTEXT_SWITCH,
+        INSN_STACK,
+        INSN_BUG,
+        INSN_NOP,
+        INSN_STAC,
+        INSN_CLAC,
+        INSN_STD,
+        INSN_CLD,
+        INSN_OTHER,
+};
 
 enum op_dest_type {
         OP_DEST_REG,
@@ -68,7 +69,7 @@ void arch_initial_func_cfi_state(struct cfi_state *state);
 
 int arch_decode_instruction(struct elf *elf, struct section *sec,
                             unsigned long offset, unsigned int maxlen,
-                            unsigned int *len, unsigned char *type,
+                            unsigned int *len, enum insn_type *type,
                             unsigned long *immediate, struct stack_op *op);
 
 bool arch_callee_saved_reg(unsigned char reg);
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 584568f27a83..0567c47a91b1 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -68,7 +68,7 @@ bool arch_callee_saved_reg(unsigned char reg)
 
 int arch_decode_instruction(struct elf *elf, struct section *sec,
                             unsigned long offset, unsigned int maxlen,
-                            unsigned int *len, unsigned char *type,
+                            unsigned int *len, enum insn_type *type,
                             unsigned long *immediate, struct stack_op *op)
 {
         struct insn insn;
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index a966b22a32ef..04572a049cfc 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -267,13 +267,6 @@ static int decode_instructions(struct objtool_file *file)
                         if (ret)
                                 goto err;
 
-                        if (!insn->type || insn->type > INSN_LAST) {
-                                WARN_FUNC("invalid instruction type %d",
-                                          insn->sec, insn->offset, insn->type);
-                                ret = -1;
-                                goto err;
-                        }
-
                         hash_add(file->insn_hash, &insn->hash, insn->offset);
                         list_add_tail(&insn->list, &file->insn_list);
                 }
diff --git a/tools/objtool/check.h b/tools/objtool/check.h
index afa6a79e0715..b881fafcf55d 100644
--- a/tools/objtool/check.h
+++ b/tools/objtool/check.h
@@ -31,7 +31,7 @@ struct instruction {
         struct section *sec;
         unsigned long offset;
         unsigned int len;
-        unsigned char type;
+        enum insn_type type;
         unsigned long immediate;
         bool alt_group, visited, dead_end, ignore, hint, save, restore, ignore_alts;
         bool retpoline_safe;