[llvm] [RISCV][MRI] Account for fixed registers when determining callee saved regs (PR #115756)

[Alexander Richardson via llvm-commits]

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@@ -0,0 +1,39 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=riscv64 -mattr=+reserve-x24 < %s | FileCheck %s
+
+define noundef signext i32 @foo() {
+; CHECK-LABEL: foo:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    li s8, 321
+; CHECK-NEXT:    li a0, 0
+; CHECK-NEXT:    ret
+  tail call void @llvm.write_register.i64(metadata !0, i64 321)
+  ret i32 0
+}
+
+declare void @llvm.write_register.i64(metadata, i64)
+
+define noundef signext i32 @bar() {
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arichardson wrote:

could add `nounwind` here to remove the .cfi directives from the test.

https://github.com/llvm/llvm-project/pull/115756