[PATCH, PR 57195] Allow mode iterators inside angle brackets

[PATCH, PR 57195] Allow mode iterators inside angle brackets

[Michael Collison]

This patch allow mode iterators inside angle brackets in machine 
description files. I
discovered the issue when attempting to use iterators on match_operand's 
as follows:

match_operand:<VW:V_widen> 0 "s_register_operand" "=w")

The function 'read_name' is nor properly handling ':' inside angle brackets.

Bootstrapped on arm-linux.

OK for trunk?

2015-08-25  Michael Collison  <michael.collison@linaro.org>

     PR other/57195
     * read-md.c (read_name): Allow mode iterators inside angle
     brackets in rtl expressions.

diff --git a/gcc/read-md.c b/gcc/read-md.c
index 9f158ec..0171fb0 100644
--- a/gcc/read-md.c
+++ b/gcc/read-md.c
@@ -399,17 +399,25 @@ read_name (struct md_name *name)
  {
    int c;
    size_t i;
+  bool in_angle_bracket;

    c = read_skip_spaces ();

    i = 0;
+  in_angle_bracket = false;
    while (1)
      {
+      if (c == '<')
+    in_angle_bracket = true;
+
+      if (c == '>')
+    in_angle_bracket = false;
+
        if (c == ' ' || c == '\n' || c == '\t' || c == '\f' || c == '\r'
        || c == EOF)
      break;
-      if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
-      || c == '(' || c == '[')
+      if (((c == ':') and (!in_angle_bracket)) || c == ')' || c == ']'
+      || c == '"' || c == '/' || c == '(' || c == '[')
      {
        unread_char (c);
        break;

-- 
Michael Collison
Linaro Toolchain Working Group
michael.collison@linaro.org

Re: [PATCH, PR 57195] Allow mode iterators inside angle brackets

[Richard Sandiford]

Michael Collison <michael.collison@linaro.org> writes:
> This patch allow mode iterators inside angle brackets in machine
> description files. I discovered the issue when attempting to use
> iterators on match_operand's as follows:
>
> match_operand:<VW:V_widen> 0 "s_register_operand" "=w")
>
> The function 'read_name' is nor properly handling ':' inside angle brackets.
>
> Bootstrapped on arm-linux.

Sorry for the slow review.

> diff --git a/gcc/read-md.c b/gcc/read-md.c
> index 9f158ec..0171fb0 100644
> --- a/gcc/read-md.c
> +++ b/gcc/read-md.c
> @@ -399,17 +399,25 @@ read_name (struct md_name *name)
>   {
>     int c;
>     size_t i;
> +  bool in_angle_bracket;
>
>     c = read_skip_spaces ();
>
>     i = 0;
> +  in_angle_bracket = false;
>     while (1)
>       {
> +      if (c == '<')
> +    in_angle_bracket = true;
> +
> +      if (c == '>')
> +    in_angle_bracket = false;
> +
>         if (c == ' ' || c == '\n' || c == '\t' || c == '\f' || c == '\r'
>         || c == EOF)
>       break;
> -      if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
> -      || c == '(' || c == '[')
> +      if (((c == ':') and (!in_angle_bracket)) || c == ')' || c == ']'
> +      || c == '"' || c == '/' || c == '(' || c == '[')
>       {
>         unread_char (c);
>         break;

I think we should have a nesting depth rather than a boolean.
It also seems more natural to skip the final "if" statement above when
inside an angle bracket, rather than treating ':' as a special case.
(We'd still break at the end of the line in the case of a missing '>',
so the error reporting shouldn't be too bad.)

I suppose logically '>' with a nesting depth of 0 should also break
the loop.

Thanks for fixing this.

Richard

Re: [PATCH, PR 57195] Allow mode iterators inside angle brackets

[Michael Collison]

Richard,

Here is a modified patch that takes your comments into account. Breaking 
on depth == 0 with '>' does not work due to the code looking for whitespace.

2015-08-25  Michael Collison  <michael.collison@linaro.org>

     PR other/57195
     * read-md.c (read_name): Allow mode iterators inside angle
     brackets in rtl expressions.


--- a/gcc/read-md.c
+++ b/gcc/read-md.c
@@ -399,20 +399,31 @@ read_name (struct md_name *name)
  {
    int c;
    size_t i;
+  int angle_bracket_depth;

    c = read_skip_spaces ();

    i = 0;
+  angle_bracket_depth = 0;
    while (1)
      {
+      if (c == '<')
+    angle_bracket_depth++;
+
+      if ((c == '>') && (angle_bracket_depth > 0))
+      angle_bracket_depth--;
+
        if (c == ' ' || c == '\n' || c == '\t' || c == '\f' || c == '\r'
        || c == EOF)
      break;
-      if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
-      || c == '(' || c == '[')
+      if (angle_bracket_depth == 0)
      {
-      unread_char (c);
-      break;
+      if (c == ':' || c == ')' || c == ']'
+          || c == '"' || c == '/' || c == '(' || c == '[')
+        {
+          unread_char (c);
+          break;
+        }
      }

        if (i == sizeof (name->buffer) - 1)

On 09/07/2015 02:46 AM, Richard Sandiford wrote:
> Michael Collison <michael.collison@linaro.org> writes:
>> This patch allow mode iterators inside angle brackets in machine
>> description files. I discovered the issue when attempting to use
>> iterators on match_operand's as follows:
>>
>> match_operand:<VW:V_widen> 0 "s_register_operand" "=w")
>>
>> The function 'read_name' is nor properly handling ':' inside angle brackets.
>>
>> Bootstrapped on arm-linux.
> Sorry for the slow review.
>
>> diff --git a/gcc/read-md.c b/gcc/read-md.c
>> index 9f158ec..0171fb0 100644
>> --- a/gcc/read-md.c
>> +++ b/gcc/read-md.c
>> @@ -399,17 +399,25 @@ read_name (struct md_name *name)
>>    {
>>      int c;
>>      size_t i;
>> +  bool in_angle_bracket;
>>
>>      c = read_skip_spaces ();
>>
>>      i = 0;
>> +  in_angle_bracket = false;
>>      while (1)
>>        {
>> +      if (c == '<')
>> +    in_angle_bracket = true;
>> +
>> +      if (c == '>')
>> +    in_angle_bracket = false;
>> +
>>          if (c == ' ' || c == '\n' || c == '\t' || c == '\f' || c == '\r'
>>          || c == EOF)
>>        break;
>> -      if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
>> -      || c == '(' || c == '[')
>> +      if (((c == ':') and (!in_angle_bracket)) || c == ')' || c == ']'
>> +      || c == '"' || c == '/' || c == '(' || c == '[')
>>        {
>>          unread_char (c);
>>          break;
> I think we should have a nesting depth rather than a boolean.
> It also seems more natural to skip the final "if" statement above when
> inside an angle bracket, rather than treating ':' as a special case.
> (We'd still break at the end of the line in the case of a missing '>',
> so the error reporting shouldn't be too bad.)
>
> I suppose logically '>' with a nesting depth of 0 should also break
> the loop.
>
> Thanks for fixing this.
>
> Richard
>

-- 
Michael Collison
Linaro Toolchain Working Group
michael.collison@linaro.org

Re: [PATCH, PR 57195] Allow mode iterators inside angle brackets

[Richard Sandiford]

Michael Collison <michael.collison@linaro.org> writes:
> Here is a modified patch that takes your comments into account. Breaking 
> on depth == 0 with '>' does not work due to the code looking for whitespace.

What goes wrong?  Just to make sure we're talking about the same thing,
I meant that in:

   (match_operand:FOO> ...

the name should be "FOO" and you should get an error on ">" when parsing
the text after the name, just like you would for:

   (match_operand:FOO] ...

It's not a big deal though, so...

> 2015-08-25  Michael Collison  <michael.collison@linaro.org>
>
>      PR other/57195
>      * read-md.c (read_name): Allow mode iterators inside angle
>      brackets in rtl expressions.

OK, thanks.

Richard

Re: [PATCH, PR 57195] Allow mode iterators inside angle brackets

[Michael Collison]

On 09/14/2015 02:34 AM, Richard Sandiford wrote:
> Michael Collison <michael.collison@linaro.org> writes:
>> Here is a modified patch that takes your comments into account. Breaking
>> on depth == 0 with '>' does not work due to the code looking for whitespace.
> What goes wrong?  Just to make sure we're talking about the same thing,
> I meant that in:
>
>     (match_operand:FOO> ...
>
> the name should be "FOO" and you should get an error on ">" when parsing
> the text after the name, just like you would for:
>
>     (match_operand:FOO] ...

When I try breaking on '>' with a nesting depth of 0 all examples of 
<FOO> fail.
>
> It's not a big deal though, so...
>
>> 2015-08-25  Michael Collison  <michael.collison@linaro.org>
>>
>>       PR other/57195
>>       * read-md.c (read_name): Allow mode iterators inside angle
>>       brackets in rtl expressions.
> OK, thanks.
Meaning okay to check the patch in?
>
> Richard
>

-- 
Michael Collison
Linaro Toolchain Working Group
michael.collison@linaro.org

Re: [PATCH, PR 57195] Allow mode iterators inside angle brackets

[Richard Sandiford]

Michael Collison <michael.collison@linaro.org> writes:
> On 09/14/2015 02:34 AM, Richard Sandiford wrote:
>> Michael Collison <michael.collison@linaro.org> writes:
>>> Here is a modified patch that takes your comments into account. Breaking
>>> on depth == 0 with '>' does not work due to the code looking for whitespace.
>> What goes wrong?  Just to make sure we're talking about the same thing,
>> I meant that in:
>>
>>     (match_operand:FOO> ...
>>
>> the name should be "FOO" and you should get an error on ">" when parsing
>> the text after the name, just like you would for:
>>
>>     (match_operand:FOO] ...
>
> When I try breaking on '>' with a nesting depth of 0 all examples of 
> <FOO> fail.

I meant break when depth == 0 before the decrement that's associated
with '>'.  I think that problem would only occur if you broke _after_
decrementing the depth.

>> It's not a big deal though, so...
>>
>>> 2015-08-25  Michael Collison  <michael.collison@linaro.org>
>>>
>>>       PR other/57195
>>>       * read-md.c (read_name): Allow mode iterators inside angle
>>>       brackets in rtl expressions.
>> OK, thanks.
> Meaning okay to check the patch in?

Yeah, it's OK to check in.

Richard