[llvm] Adding support in llvm-exegesis for Aarch64 for handling FPR64/128, PPR16 and ZPR128 reg class. (PR #127564)

[Sjoerd Meijer via llvm-commits]

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@@ -0,0 +1,45 @@
+REQUIRES: aarch64-registered-target
+
+## PPR Register Class Initialization Testcase
+## Ideally, we should use PTRUE_{B/H/S/D} instead of FADDV_VPZ_D for an isolated test case; however, Exegesis does not yet support PTRUE_{B/H/S/D}.
+RUN: llvm-exegesis -mcpu=neoverse-v2 -mode=latency --dump-object-to-disk=%d --opcode-name=FADDV_VPZ_D 2>&1 | FileCheck %s --check-prefix=PPR
+RUN: llvm-objdump -d %d > %t.s
+RUN: FileCheck %s --check-prefix=PPR_ASM < %t.s
+PPR-NOT: setRegTo is not implemented, results will be unreliable
+PPR: assembled_snippet: {{.*}}C0035FD6
+PPR_ASM: {{<foo>:}}
+PPR_ASM: ptrue p{{[0-9]+}}.b
+PPR_ASM-NEXT: dupm z{{[0-9]+}}.s, #0x1
+PPR_ASM-NEXT: faddv d{{[0-9]+}}, p{{[0-9]+}}, z{{[0-9]+}}
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sjoerdmeijer wrote:

This is a nitpick, but I think we are testing the same things with:

    setRegTo is not implemented, results will be unreliable

and 

    PPR_ASM-NEXT: dupm z{{[0-9]+}}.s, #0x1

So I think we can just test one thing, and the best thing to check is the assembly. 
I also don't know what this means or is testing:

    PPR: assembled_snippet: {{.*}}C0035FD6

Here's my suggestion for this test just to clean this up, and with a bit of extra formatting and spacing to make it slightly more easy to read (in my opinion):
```
    ## PPR Register Class Initialization Testcase
    ## Ideally, we should use PTRUE_{B/H/S/D} instead of FADDV_VPZ_D for an isolated test case; however,             
    Exegesis does not yet support PTRUE_{B/H/S/D}.

    RUN: llvm-exegesis -mcpu=neoverse-v2 -mode=latency --dump-object-to-disk=%d --opcode- 
    name=FADDV_VPZ_D 2>&1 | FileCheck %s --check-prefix=PPR
    RUN: llvm-objdump -d %d > %t.s
    RUN: FileCheck %s --check-prefix=PPR_ASM < %t.s

    PPR_ASM:       {{<foo>:}}
    PPR_ASM:       ptrue p{{[0-9]+}}.b
    PPR_ASM-NEXT:  dupm z{{[0-9]+}}.s, #0x1
    PPR_ASM-NEXT:  faddv d{{[0-9]+}}, p{{[0-9]+}}, z{{[0-9]+}}
```

Can you give the other tests below a similar treatment?

https://github.com/llvm/llvm-project/pull/127564