[PATCH] x86/gas: support quoted address scale factor in AT&T syntax

[Jan Beulich <jbeulich@suse.com>]

An earlier attempt (e68c3d59acd0 ["x86: better respect quotes in
parse_operands()"]) needed undoing (cc0f96357e0b ["x86: permit
parenthesized expressions again as addressing scale factor"]) as far its
effect here went. As indicated back then, the issue is the backwards
scanning of the operand string to find the matching opening parenthesis.
Switch to forward scanning, finding the last outermost unquoted opening
parenthesis (which is the one matching the trailing closing one).

--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -11620,25 +11620,32 @@ i386_att_operand (char *operand_string)
       if (*base_string == ')')
 	{
 	  char *temp_string;
-	  unsigned int parens_not_balanced = 1;
+	  unsigned int parens_not_balanced = 0;
+	  bool in_quotes = false;
 
 	  /* We've already checked that the number of left & right ()'s are
-	     equal, so this loop will not be infinite.  */
-	  do
+	     equal, and that there's a matching set of double quotes.  */
+	  end_op = base_string;
+	  for (temp_string = op_string; temp_string < end_op; temp_string++)
 	    {
-	      base_string--;
-	      if (*base_string == ')')
-		parens_not_balanced++;
-	      if (*base_string == '(')
-		parens_not_balanced--;
+	      if (*temp_string == '\\' && temp_string[1] == '"')
+		++temp_string;
+	      else if (*temp_string == '"')
+		in_quotes = !in_quotes;
+	      else if (!in_quotes)
+		{
+		  if (*temp_string == '(' && !parens_not_balanced++)
+		    base_string = temp_string;
+		  if (*temp_string == ')')
+		    --parens_not_balanced;
+		}
 	    }
-	  while (parens_not_balanced && *base_string != '"');
 
 	  temp_string = base_string;
 
 	  /* Skip past '(' and whitespace.  */
-	  if (*base_string == '(')
-	    ++base_string;
+	  gas_assert (*base_string == '(');
+	  ++base_string;
 	  if (is_space_char (*base_string))
 	    ++base_string;
 
--- a/gas/testsuite/gas/i386/sib-intel.d
+++ b/gas/testsuite/gas/i386/sib-intel.d
@@ -34,6 +34,10 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	8b 04 40             	mov    eax,DWORD PTR \[eax\+eax\*2\]
 [ 	]*[a-f0-9]+:	8b 04 80             	mov    eax,DWORD PTR \[eax\+eax\*4\]
 [ 	]*[a-f0-9]+:	8b 04 c0             	mov    eax,DWORD PTR \[eax\+eax\*8\]
+[ 	]*[a-f0-9]+:	8b 14 08             	mov    edx,DWORD PTR \[eax\+ecx\*1\]
+[ 	]*[a-f0-9]+:	8b 14 48             	mov    edx,DWORD PTR \[eax\+ecx\*2\]
+[ 	]*[a-f0-9]+:	8b 14 88             	mov    edx,DWORD PTR \[eax\+ecx\*4\]
+[ 	]*[a-f0-9]+:	8b 14 c8             	mov    edx,DWORD PTR \[eax\+ecx\*8\]
 [ 	]*[a-f0-9]+:	8b 04 25 e2 ff ff ff 	mov    eax,DWORD PTR \[eiz\*1-0x1e\]
 [ 	]*[a-f0-9]+:	8b 04 65 e2 ff ff ff 	mov    eax,DWORD PTR \[eiz\*2-0x1e\]
 [ 	]*[a-f0-9]+:	8b 04 a5 e2 ff ff ff 	mov    eax,DWORD PTR \[eiz\*4-0x1e\]
--- a/gas/testsuite/gas/i386/sib.d
+++ b/gas/testsuite/gas/i386/sib.d
@@ -33,6 +33,10 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	8b 04 40             	mov    \(%eax,%eax,2\),%eax
 [ 	]*[a-f0-9]+:	8b 04 80             	mov    \(%eax,%eax,4\),%eax
 [ 	]*[a-f0-9]+:	8b 04 c0             	mov    \(%eax,%eax,8\),%eax
+[ 	]*[a-f0-9]+:	8b 14 08             	mov    \(%eax,%ecx,1\),%edx
+[ 	]*[a-f0-9]+:	8b 14 48             	mov    \(%eax,%ecx,2\),%edx
+[ 	]*[a-f0-9]+:	8b 14 88             	mov    \(%eax,%ecx,4\),%edx
+[ 	]*[a-f0-9]+:	8b 14 c8             	mov    \(%eax,%ecx,8\),%edx
 [ 	]*[a-f0-9]+:	8b 04 25 e2 ff ff ff 	mov    -0x1e\(,%eiz,1\),%eax
 [ 	]*[a-f0-9]+:	8b 04 65 e2 ff ff ff 	mov    -0x1e\(,%eiz,2\),%eax
 [ 	]*[a-f0-9]+:	8b 04 a5 e2 ff ff ff 	mov    -0x1e\(,%eiz,4\),%eax
--- a/gas/testsuite/gas/i386/sib.s
+++ b/gas/testsuite/gas/i386/sib.s
@@ -30,6 +30,14 @@ foo:
 	mov	(%eax, %eax, (1 << 1)), %eax
 	mov	(%eax, %eax, (1 << 2)), %eax
 	mov	(%eax, %eax, (1 << 3)), %eax
+	.equ "scale(1)", 1
+	mov	(%eax, %ecx, "scale(1)"), %edx
+	.equiv "scale[2]", 2
+	mov	(%eax, %ecx, "scale[2]"), %edx
+	.eqv "scale{4}", 4
+	mov	(%eax, %ecx, "scale{4}"), %edx
+	.set "scale<8>", 8
+	mov	(%eax, %ecx, "scale<8>"), %edx
 	.intel_syntax noprefix
         mov    eax,DWORD PTR [eiz*1-30]
         mov    eax,DWORD PTR [eiz*2-30]