Add ratified Zacas extension

[ved-rivos]

Description

This patch introduces a coverage model and the generated test cases using riscv_ctg. The tests have been generated using the following command:

riscv_ctg.py --cgf coverage/dataset.cgf --cgf coverage/zicond.cgf -bi rv32i -d rv32tests/
riscv_ctg.py --cgf coverage/dataset.cgf --cgf coverage/zicond.cgf -bi rv64i -d rv64tests/

The generated tests are placed in
rv32i_m/Zacas/src
rv64i_m/Zacas/src

Related Issues

Ratified/Unratified Extensions

• Ratified
• Unratified

List Extensions

Zacas specification: https://github.com/riscv/riscv-zacas

Reference Model Used

• [ X] SAIL
• [ X] Spike
• [ ] Other - < SPECIFY HERE >

Mandatory Checklist:

• [ x] All tests are compliant with the test-format spec present in this repo ?
• [ ] Ran the new tests on RISCOF with SAIL/Spike as reference model successfully ?
• [ ] Ran the new tests on RISCOF in coverage mode
• [ ] Link to Google-Drive folder containing the new coverage reports (See this for more info): < SPECIFY HERE >
• [ ] Link to PR in RISCV-ISAC from which the reports were generated : < SPECIFY HERE >
• [ X] Changelog entry created with a minor patch

Optional Checklist:

• [x ] RISCV-V CTG PR link if tests were generated using it : Add unratified Zacas extension  riscv-software-src/riscv-ctg#73
• [ ] Were the tests hand-written/modified ?
• [ ] Have you run these on any hard DUT model ? Please specify name and provide link if possible in the description
• If you have modified arch_test.h Please provide a detailed description of the changes in the Description section above.

[UmerShahidengr]

The CTG PR (riscv-software-src/riscv-ctg#73) has already been merged, these are the generated tests from a merged coverpoint group file, good to go from my side.

[UmerShahidengr]

Its parallel riscv-ctg PR has already been merged since August last year, so I am merging these tests too.