[llvm] [X86] Correct Zen4 Scheduling References and Mismatches (PR #128030)

[Simon Pilgrim via llvm-commits]

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@@ -9,45 +9,45 @@
 // This file defines the machine model for Znver4 to support instruction
 // scheduling and other instruction cost heuristics.
 // Based on:
-//  * AMD Software Optimization Guide for AMD Family 19h Processors.
-//    https://www.amd.com/system/files/TechDocs/56665.zip
+//  * AMD Software Optimization Guide for the AMD Zen4 Microarchitecture.
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RKSimon wrote:

Technically zen4 is fam 19h as well (and zen5 is fam 1Ah) - it just has later model numbers in the cpuid

https://github.com/llvm/llvm-project/pull/128030