Hi -
I don't know if this behavior has been in the CCode inliner before but I just noticed that the inliner will forcefully convert iVars to temps if that iVar is only explicitly referred to in a single method. Like, for example here:
Interpreter>>getFoo ^self cCode: 'foo'
Interpreter>>setFoo: fooValue foo := fooValue.
The above will cause the inliner to remove foo from the regular interpreter variables (even if declared via #declareCVarsIn:) and move it into #setFoo:. With the foreseeable result of creating total and utter nonsense in the resulting C code.
Has anyone seen that before?
Cheers, - Andreas
This was done on purpose years ago to inline all the variables in the GC logic.
If you have one accessor and one usage of the variable in another routine and say not to inline the accessor, then the inliner won't fold the global into a local variable. Your code example follows the rules nicely because you've only one usage of the foo variable we can see and why make it a global...
On 8-Jun-06, at 1:53 PM, Andreas Raab wrote:
Hi -
I don't know if this behavior has been in the CCode inliner before but I just noticed that the inliner will forcefully convert iVars to temps if that iVar is only explicitly referred to in a single method. Like, for example here:
Interpreter>>getFoo ^self cCode: 'foo'
Interpreter>>setFoo: fooValue foo := fooValue.
The above will cause the inliner to remove foo from the regular interpreter variables (even if declared via #declareCVarsIn:) and move it into #setFoo:. With the foreseeable result of creating total and utter nonsense in the resulting C code.
Has anyone seen that before?
Cheers,
- Andreas
-- ======================================================================== === John M. McIntosh johnmci@smalltalkconsulting.com 1-800-477-2659 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com ======================================================================== ===
The pattern to avoid this inlining "strangeness" would be
Interpreter>>getFoo ^self cCode: 'foo' inSmalltalk: [foo]
so the inliner sees the second access.
- Bert -
Am 09.06.2006 um 00:47 schrieb John M McIntosh:
This was done on purpose years ago to inline all the variables in the GC logic.
If you have one accessor and one usage of the variable in another routine and say not to inline the accessor, then the inliner won't fold the global into a local variable. Your code example follows the rules nicely because you've only one usage of the foo variable we can see and why make it a global...
On 8-Jun-06, at 1:53 PM, Andreas Raab wrote:
Hi -
I don't know if this behavior has been in the CCode inliner before but I just noticed that the inliner will forcefully convert iVars to temps if that iVar is only explicitly referred to in a single method. Like, for example here:
Interpreter>>getFoo ^self cCode: 'foo'
Interpreter>>setFoo: fooValue foo := fooValue.
The above will cause the inliner to remove foo from the regular interpreter variables (even if declared via #declareCVarsIn:) and move it into #setFoo:. With the foreseeable result of creating total and utter nonsense in the resulting C code.
Has anyone seen that before?
Cheers,
- Andreas
Actually I think I've seen
self touch: foo
which is removed by the CCodeGenerator, mind I've not check this to see when it's removed in relationship to the inliner logic.
On 9-Jun-06, at 1:08 AM, Bert Freudenberg wrote:
The pattern to avoid this inlining "strangeness" would be
Interpreter>>getFoo ^self cCode: 'foo' inSmalltalk: [foo]
so the inliner sees the second access.
- Bert -
Am 09.06.2006 um 00:47 schrieb John M McIntosh:
This was done on purpose years ago to inline all the variables in the GC logic.
If you have one accessor and one usage of the variable in another routine and say not to inline the accessor, then the inliner won't fold the global into a local variable. Your code example follows the rules nicely because you've only one usage of the foo variable we can see and why make it a global...
On 8-Jun-06, at 1:53 PM, Andreas Raab wrote:
Hi -
I don't know if this behavior has been in the CCode inliner before but I just noticed that the inliner will forcefully convert iVars to temps if that iVar is only explicitly referred to in a single method. Like, for example here:
Interpreter>>getFoo ^self cCode: 'foo'
Interpreter>>setFoo: fooValue foo := fooValue.
The above will cause the inliner to remove foo from the regular interpreter variables (even if declared via #declareCVarsIn:) and move it into #setFoo:. With the foreseeable result of creating total and utter nonsense in the resulting C code.
Has anyone seen that before?
Cheers,
- Andreas
-- ======================================================================== === John M. McIntosh johnmci@smalltalkconsulting.com 1-800-477-2659 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com ======================================================================== ===
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John M McIntosh