On Mon, 27 Jan 2025 08:35:44 GMT, Jatin Bhateja <jbhat...@openjdk.org> wrote:
>> Hi All, >> >> This patch adds C2 compiler support for various Float16 operations added by >> [PR#22128](https://github.com/openjdk/jdk/pull/22128) >> >> Following is the summary of changes included with this patch:- >> >> 1. Detection of various Float16 operations through inline expansion or >> pattern folding idealizations. >> 2. Float16 operations like add, sub, mul, div, max, and min are inferred >> through pattern folding idealization. >> 3. Float16 SQRT and FMA operation are inferred through inline expansion and >> their corresponding entry points are defined in the newly added Float16Math >> class. >> - These intrinsics receive unwrapped short arguments encoding IEEE >> 754 binary16 values. >> 5. New specialized IR nodes for Float16 operations, associated >> idealizations, and constant folding routines. >> 6. New Ideal type for constant and non-constant Float16 IR nodes. Please >> refer to [FAQs >> ](https://github.com/openjdk/jdk/pull/22754#issuecomment-2543982577)for more >> details. >> 7. Since Float16 uses short as its storage type, hence raw FP16 values are >> always loaded into general purpose register, but FP16 ISA generally operates >> over floating point registers, thus the compiler injects reinterpretation IR >> before and after Float16 operation nodes to move short value to floating >> point register and vice versa. >> 8. New idealization routines to optimize redundant reinterpretation chains. >> HF2S + S2HF = HF >> 9. X86 backend implementation for all supported intrinsics. >> 10. Functional and Performance validation tests. >> >> Kindly review the patch and share your feedback. >> >> Best Regards, >> Jatin > > Jatin Bhateja has updated the pull request incrementally with one additional > commit since the last revision: > > Copyright header fix Some more minor comments. src/hotspot/share/opto/addnode.cpp line 1546: > 1544: > 1545: // As per IEEE 754 specification, floating point comparison consider > +ve and -ve > 1546: // zeros as equals. Thus, performing signed integral comparison for > max value Should be "min value detection". src/hotspot/share/opto/addnode.cpp line 1624: > 1622: // As per IEEE 754 specification, floating point comparison consider > +ve and -ve > 1623: // zeros as equals. Thus, performing signed integral comparison for > min value > 1624: // detection. Should be "max value detection". src/hotspot/share/opto/divnode.cpp line 848: > 846: // If the dividend is a constant zero > 847: // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) > 848: // Test TypeF::ZERO is not sufficient as it could be negative zero Comment should be TypeH:ZERO is not sufficient ------------- PR Review: https://git.openjdk.org/jdk/pull/22754#pullrequestreview-2576801437 PR Review Comment: https://git.openjdk.org/jdk/pull/22754#discussion_r1931347845 PR Review Comment: https://git.openjdk.org/jdk/pull/22754#discussion_r1931347430 PR Review Comment: https://git.openjdk.org/jdk/pull/22754#discussion_r1931376932
