Bug 151458 - Consider adding value constraints, such as that a value is guaranteed non-negative, to B3
Summary: Consider adding value constraints, such as that a value is guaranteed non-neg...
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: All All
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks: 154319
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Reported: 2015-11-19 12:48 PST by Filip Pizlo
Modified: 2016-02-16 18:26 PST (History)
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Description Filip Pizlo 2015-11-19 12:48:28 PST 
Some options:

- Like LLVM, allow load instructions to specify a range of possible values that it could return.

- Have a LoadUnsigned.

- Have a variant of ZExt/SExt that guarantees that the sign bit is zero.