[clang] [llvm] [RISCV] Add partial support for -fzero-call-used-regs (PR #194883)

[Sam Elliott via cfe-commits]

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@@ -0,0 +1,297 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc < %s -verify-machineinstrs -mtriple=riscv64-unknown-unknown | FileCheck %s  --check-prefixes=CHECK,64-BITS
+; RUN: llc < %s -verify-machineinstrs -mtriple=riscv32-unknown-unknown | FileCheck %s --check-prefixes=CHECK,32-BITS
+
+target triple = "riscv64-unknown-linux-gnu"
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lenary wrote:

```suggestion
```

Implied by the arguments to llc.

https://github.com/llvm/llvm-project/pull/194883