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...

    Use loop predicate to remove array range checks in a loop.

   

original loop

for (int i = init,  i < limit;  i += stride) {  // loop with array range check
    ...
    if (scale*i + offset < a.length) {  // array range check
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="e242b0a48c870eab-b7df9170-4d0e47f9-aa6bbe75-9fea52996dac040297cef274"><ac:plain-text-body><![CDATA[        ... a[scale*i+offset] ...
]]></ac:plain-text-body></ac:structured-macro>
    } else raise_uncommon_trap();
    ...
}

   

 

after loop predication

if ( scale * imax + offset < a.length ) {  // loop predicate. imax is the maximum value of i where init <= i < limit
    for (int i = init,  i < limit;  i += stride) {  // loop without array range check
         ...
<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="532b025ae15d953d-acd5a52d-4fff42c8-b74184ba-ed29c5eaba1938eb6db4b29d"><ac:plain-text-body><![CDATA[         ... a[scale*i+offset] ...
]]></ac:plain-text-body></ac:structured-macro>
         ...
    }
} else raise_uncommon_trap();