1987-03-09 19:15:41 +00:00
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/*
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* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
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* See the copyright notice in the ACK home directory, in the file "Copyright".
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*/
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1984-11-26 14:35:32 +00:00
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/* C O N S T A N T P R O P A G A T I O N */
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extern line_p unique_def(); /* ( line_p use; bblock_p b; short *defnr_out;)
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* See if there is a unique explicit definition
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* of the variable used by 'use' that
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* reaches 'use'.
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*/
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extern bool value_known(); /* (line_p def; offset *val_out)
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* See if the value stored by definition 'def'
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* is known statically (i.e. is a constant).
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*/
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extern fold_const(); /* (line_p l; bblock_p b; offset val)
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* Perform the substitutions required for
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* constant folding.
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*/
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extern bool is_use(); /* (line_p l)
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* See if 'l' is a use of a variable.
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*/
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extern bool affected(); /* (line_p use,l; short v)
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* See if the variable referenced by 'use' may
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* be changed by instruction l, which is
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* either a cal, cai or an indirect assignment.
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*/
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