linux-kernel - [PATCH 12.5/13] objtool: Reflow handle_jump

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Date:   Thu, 13 May 2021 16:15:50 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     x86@...nel.org, jpoimboe@...hat.com, jbaron@...mai.com,
        rostedt@...dmis.org, ardb@...nel.org
Cc:     linux-kernel@...r.kernel.org
Subject: [PATCH 12.5/13] objtool: Reflow handle_jump_alt()


Subject: objtool: Reflow handle_jump_alt()
From: Peter Zijlstra <peterz@...radead.org>
Date: Thu May 13 13:52:46 CEST 2021

Miroslav figured the code flow in handle_jump_alt() was sub-optimal
with that goto. Reflow the code to make it clearer.

Reported-by: Miroslav Benes <mbenes@...e.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 tools/objtool/check.c |   22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1225,17 +1225,9 @@ static int handle_jump_alt(struct objtoo
 			   struct instruction *orig_insn,
 			   struct instruction **new_insn)
 {
-	if (orig_insn->type == INSN_NOP) {
-do_nop:
-		if (orig_insn->len == 2)
-			file->jl_nop_short++;
-		else
-			file->jl_nop_long++;
+	if (orig_insn->type != INSN_JUMP_UNCONDITIONAL &&
+	    orig_insn->type != INSN_NOP) {
 
-		return 0;
-	}
-
-	if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {
 		WARN_FUNC("unsupported instruction at jump label",
 			  orig_insn->sec, orig_insn->offset);
 		return -1;
@@ -1252,7 +1244,15 @@ static int handle_jump_alt(struct objtoo
 			       orig_insn->offset, orig_insn->len,
 			       arch_nop_insn(orig_insn->len));
 		orig_insn->type = INSN_NOP;
-		goto do_nop;
+	}
+
+	if (orig_insn->type == INSN_NOP) {
+		if (orig_insn->len == 2)
+			file->jl_nop_short++;
+		else
+			file->jl_nop_long++;
+
+		return 0;
 	}
 
 	if (orig_insn->len == 2)