[RFC PATCH] gas: Do not eliminate '\()' if there is still .irp is not fully translated

[Haochen Jiang]

Hi all,

Recently I found that if I am using nested .irp with \(), it would be wrongly
translated. It is caused by \() being eliminated too early. I tried with the
following patch to add an extra bool passing in sub_actual to record if there
is any .irp in mnemonic not handled before \() is handled.

The patch works for current x86 testcases. I may also try with aarch64 machines
if I could find one since macros are widely used in aarch testcases.

I suppose there might be a better option to do that so I called this an RFC
patch. The current method is quite straight-forward but seems too
straight-forward. Discussion is welcomed.

Thx,
Haochen

---
 
During AVX10.2 testcases refinement, I found that if the following .irp were
used, it would not be correctly translated:

	.irp m, madd, msub, nmadd, nmsub
	.irp n, 132, 213, 231
	vf\m\n\()nepbf16	%zmm4, %zmm5, %zmm6
	vf\m\n\()nepbf16	0x10000000(%esp, %esi, 8), %zmm5, %zmm6{%k7}
	vf\m\n\()nepbf16	(%ecx){1to32}, %zmm5, %zmm6
	vf\m\n\()nepbf16	8128(%ecx), %zmm5, %zmm6
	vf\m\n\()nepbf16	-256(%edx){1to32}, %zmm5, %zmm6{%k7}{z}
	.endr
	.endr

It is caused by macro_expand_body(), the function will directly eliminate \()
when first met. This is when \m gets translated but \n does not under this
scenario. However, it should be eliminated after \n is handled, or it will
result into vfmadd\nnepbf16. It leads to invalid character '\' eventually.

gas/ChangeLog:

	* macro.c (sub_actual): Pass the status if the exact sequence is
	found or not.
	(macro_expand_body): Change function call due to the addition of
	bool*. Do not eliminate '\()' if any .irp before '\()' is not fully
	translated.
---
 gas/macro.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/gas/macro.c b/gas/macro.c
index 8b376f7f490..ee4caac9cc7 100644
--- a/gas/macro.c
+++ b/gas/macro.c
@@ -754,7 +754,7 @@ get_apost_token (size_t idx, sb *in, sb *name, int kind)
 
 static size_t
 sub_actual (size_t start, sb *in, sb *t, struct htab *formal_hash,
-	    int kind, sb *out, int copyifnotthere)
+	    int kind, sb *out, int copyifnotthere, bool *found)
 {
   size_t src;
   formal_entry *ptr;
@@ -778,6 +778,7 @@ sub_actual (size_t start, sb *in, sb *t, struct htab *formal_hash,
 	{
 	  sb_add_sb (out, &ptr->def);
 	}
+      *found = true;
     }
   else if (kind == '&')
     {
@@ -786,15 +787,18 @@ sub_actual (size_t start, sb *in, sb *t, struct htab *formal_hash,
       sb_add_sb (out, t);
       if (src != start && in->ptr[src - 1] == '&')
 	sb_add_char (out, '&');
+      *found = true;
     }
   else if (copyifnotthere)
     {
       sb_add_sb (out, t);
+      *found = true;
     }
   else
     {
       sb_add_char (out, '\\');
       sb_add_sb (out, t);
+      *found = false;
     }
   return src;
 }
@@ -811,6 +815,7 @@ macro_expand_body (sb *in, sb *out, formal_entry *formals,
   int inquote = 0, macro_line = 0;
   formal_entry *loclist = NULL;
   const char *err = NULL;
+  bool found = true;
 
   sb_new (&t);
 
@@ -822,7 +827,8 @@ macro_expand_body (sb *in, sb *out, formal_entry *formals,
 	  if (flag_mri)
 	    {
 	      if (src + 1 < in->len && in->ptr[src + 1] == '&')
-		src = sub_actual (src + 2, in, &t, formal_hash, '\'', out, 1);
+		src = sub_actual (src + 2, in, &t, formal_hash, '\'',
+				  out, 1, &found);
 	      else
 		sb_add_char (out, in->ptr[src++]);
 	    }
@@ -830,13 +836,14 @@ macro_expand_body (sb *in, sb *out, formal_entry *formals,
 	    {
 	      /* Permit macro parameter substitution delineated with
 		 an '&' prefix and optional '&' suffix.  */
-	      src = sub_actual (src + 1, in, &t, formal_hash, '&', out, 0);
+	      src = sub_actual (src + 1, in, &t, formal_hash, '&',
+				out, 0, &found);
 	    }
 	}
       else if (in->ptr[src] == '\\')
 	{
 	  src++;
-	  if (src < in->len && in->ptr[src] == '(')
+	  if (src < in->len && in->ptr[src] == '(' && found)
 	    {
 	      /* Sub in till the next ')' literally.  */
 	      src++;
@@ -904,7 +911,8 @@ macro_expand_body (sb *in, sb *out, formal_entry *formals,
 	  else
 	    {
 	      sb_reset (&t);
-	      src = sub_actual (src, in, &t, formal_hash, '\'', out, 0);
+	      src = sub_actual (src, in, &t, formal_hash, '\'',
+				out, 0, &found);
 	    }
 	}
       else if ((flag_macro_alternate || flag_mri)
@@ -923,7 +931,7 @@ macro_expand_body (sb *in, sb *out, formal_entry *formals,
 	      sb_reset (&t);
 	      src = sub_actual (src, in, &t, formal_hash,
 				(macro_strip_at && inquote) ? '@' : '\'',
-				out, 1);
+				out, 1, &found);
 	    }
 	  else
 	    {
-- 
2.31.1