diff mbox series

[3/6] gas: no md_cons_align() for .nop{,s}

Message ID 8857c2de-39b6-43c7-93d9-43554ef317c3@suse.com
State Unresolved
Headers
Series correct and further utilize x86'es last-insn tracking |

Checks

Context Check Description
snail/binutils-gdb-check warning Git am fail log

Commit Message

Jan Beulich Nov. 24, 2023, 9:04 a.m. UTC 
  .nop and .nops generate code, not data. Hence them invoking
md_cons_align() is at best inappropriate. In fact it actually gets in
the of x86'es state maintenance involving i386_cons_align().
---
I also consider it at least a little suspicious that all common code
invocations of md_cons_align() have an argument of 1 passed to it:
What's the point of that argument then? Target specific code invoking
their own target hook can surely deal with passing appropriate arguments
other than 1.
diff mbox series

Patch

--- a/gas/read.c
+++ b/gas/read.c
@@ -3466,10 +3466,6 @@  s_nop (int ignore ATTRIBUTE_UNUSED)
   md_flush_pending_output ();
 #endif
 
-#ifdef md_cons_align
-  md_cons_align (1);
-#endif
-
   SKIP_WHITESPACE ();
   expression (&exp);
   demand_empty_rest_of_line ();
@@ -3519,10 +3515,6 @@  s_nops (int ignore ATTRIBUTE_UNUSED)
   md_flush_pending_output ();
 #endif
 
-#ifdef md_cons_align
-  md_cons_align (1);
-#endif
-
   SKIP_WHITESPACE ();
   expression (&exp);
   /* Note - this expression is tested for an absolute value in
--- a/gas/testsuite/gas/i386/align-branch-6.e
+++ b/gas/testsuite/gas/i386/align-branch-6.e
@@ -1,2 +1,2 @@ 
 .*: Assembler messages:
-.*:4: Warning: `constant directive` skips -malign-branch-boundary on `jnc`
+.*:5: Warning: `constant directive` skips -malign-branch-boundary on `jnc`
--- a/gas/testsuite/gas/i386/lfence-byte.d
+++ b/gas/testsuite/gas/i386/lfence-byte.d
@@ -27,4 +27,13 @@  Disassembly of section .text:
  +[a-f0-9]+:	f3 c3                	repz ret
  +[a-f0-9]+:	c3                   	ret
  +[a-f0-9]+:	f3 ff d0             	repz call \*%eax
+
+[a-f0-9]+ <directive>:
+ +[a-f0-9]+:	90                   	nop
+ +[a-f0-9]+:	0f ae e8             	lfence
+ +[a-f0-9]+:	ff d0                	call   \*%eax
+ +[a-f0-9]+:	8d 76 00             	lea    (0x)?0\(%esi\),%esi
+ +[a-f0-9]+:	83 0c 24 00          	orl    \$0x0,\(%esp\)
+ +[a-f0-9]+:	0f ae e8             	lfence
+ +[a-f0-9]+:	c3                   	ret
 #pass
--- a/gas/testsuite/gas/i386/lfence-byte.s
+++ b/gas/testsuite/gas/i386/lfence-byte.s
@@ -21,3 +21,10 @@  _start:
 	call *%eax
 	.data
 	.byte 0
+
+	.text
+directive:
+	.nop
+	call	*%eax
+	.nops 3
+	ret