diff --git a/archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/2022-12-19-abductee_org-cool-any-similar-comments-on-cuda12-ptx-sass.md b/archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/2022-12-19-abductee_org-cool-any-similar-comments-on-cuda12-ptx-sass.md new file mode 100644 index 0000000..ebedb0e --- /dev/null +++ b/archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/2022-12-19-abductee_org-cool-any-similar-comments-on-cuda12-ptx-sass.md @@ -0,0 +1,44 @@ +--- +title: "@NOTimothyLottes cool!" +type: archive +source: twitter +source_url: "https://x.com/abductee_org/status/1604899144786620416" +author: "Michael Sänger (💉 3/2)" +handle: abductee_org +post_id: "1604899144786620416" +date: 2022-12-19 +archived: 2026-08-26 +draft: false +tags: + - archive + - twitter + - NOTimothyLottes +description: "@NOTimothyLottes cool!" +in_reply_to: "" +parent_post_id: "1604260386659880961" +--- + +## Source + +- URL: https://x.com/abductee_org/status/1604899144786620416 +- Author: Michael Sänger (💉 3/2) (@abductee_org) +- Posted: 2022-12-19 17:59:08 + +## Branch + +**1/** **@abductee_org** ^1604899144786620416 + +**@NOTimothyLottes** + +cool! +any similar comments on cuda12/ptx/sass? ;) + +**2/** **@NOTimothyLottes** ^1605588165384814592 + +**@abductee_org** + +https://x.com/NOTimothyLottes/status/1596096198758244352 and https://x.com/NOTimothyLottes/status/1596094389641965570 + +## Related + +- Spine: [[archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments]] diff --git a/archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/index.md b/archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/index.md new file mode 100644 index 0000000..50690b2 --- /dev/null +++ b/archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/index.md @@ -0,0 +1,53 @@ +--- +title: "RDNA3 ISA Guide Comments" +type: archive +source: twitter +source_url: "https://x.com/NOTimothyLottes/status/1604260386659880961" +author: "NOTimothyLottes" +handle: NOTimothyLottes +post_id: "1604260386659880961" +date: 2022-12-17 +archived: 2026-08-26 +draft: false +tags: + - archive + - twitter + - NOTimothyLottes +description: "RDNA3 ISA Guide Comments" +in_reply_to: "" +--- + +## Source + +- URL: https://x.com/NOTimothyLottes/status/1604260386659880961 +- Author: NOTimothyLottes (@NOTimothyLottes) +- Posted: 2022-12-17 23:40:56 + +## Thread + +**1/** **@NOTimothyLottes** ^1604260386659880961 + +RDNA3 ISA Guide Comments +(1.) Driver: Instead of padding 256 bytes with S_CODE_END, how about putting the next shader in there (looking at you post process passes, with consistent temporal ordering). + +Branches: [[archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments/2022-12-19-abductee_org-cool-any-similar-comments-on-cuda12-ptx-sass]] + +**2/** **@NOTimothyLottes** ^1604263778106892292 + +(2.) VGPR increase: Traditionally with 8 VGPR allocation granularity the target would be 64 VGPRs/wave or under. Now with 12 granularity a compiler can likely miss the 64 VGPR target and get to 96 without seeing a problem in those cases. + +**3/** **@NOTimothyLottes** ^1604265437281271809 + +(3.) S_MEMREALTIME went to S_SENDMSG_RTN+S_WAITCNT (side effect, more opcode space), these would include a code motion barrier anyway. Would like a VK extension to query the "typically 100 MHz" fixed frequency amount: lots of nice things you can do with a real shader wallclock! + +**4/** **@NOTimothyLottes** ^1604267130299596803 + +(4.) Really nice cache control via {SRD llc_noalloc, opcode DLC/SLC/GLC}. Wish there was a way to access using layout qualifier aliasing in VK. Esp 'STREAM' on loads, to avoid cache pollution when no reuse is known by the developer. + +**5/** **@NOTimothyLottes** ^1604268044464930817 + +(5.) "Dealloc VGPRs" - CS waves need to wait until all pending stores return "finished" before the wave exits. But now the VGPRs can be returned before waiting (to be used by a new workgroup). However, persistent or semi-persistent waves is still the way to go IMO. + +**6/** **@NOTimothyLottes** ^1604485986234388481 + +(6.) V_PERMLANE64 - Likely no more V_READLANE waterfall for dynamic index shuffle in Wave64 mode (don't have a RDNA3 to dump disassembly), but will LDS still be faster than the complex sequence of {PERMLANE16, PERMLANEX16, PERMLANE64} related logic? diff --git a/archive/threads/NOTimothyLottes/index.md b/archive/threads/NOTimothyLottes/index.md index 7d2dd3a..d46943e 100644 --- a/archive/threads/NOTimothyLottes/index.md +++ b/archive/threads/NOTimothyLottes/index.md @@ -14,6 +14,7 @@ tags: - [[archive/threads/NOTimothyLottes/2022-11-08-example-of-bind-everything-once-layout-aliasing]] - [[archive/threads/NOTimothyLottes/2022-11-09-if-only-pc-vendors-with-open-isas]] - [[archive/threads/NOTimothyLottes/2022-11-13-my-prefered-method-of-managing-application-data]] +- [[archive/threads/NOTimothyLottes/2022-12-17-rdna3-isa-guide-comments]] - [[archive/threads/NOTimothyLottes/2023-04-28-https-gpuopen-com-learn-rgp-1-15-enhanced-isa]] - [[archive/threads/NOTimothyLottes/2023-05-03-found-some-of-my-old-blogs-thread-looking-back-an]] - [[archive/threads/NOTimothyLottes/2023-06-20-how-about-a-mega-thread-on-the-mechanics-of-cpu]]