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

[Craig Topper via llvm-commits]

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@@ -0,0 +1,12 @@
+; RUN: not --crash llc -mtriple=m68k -mattr=+reserve-a0 < %s 2>&1 | FileCheck %s
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topperc wrote:

a0 isn't a callee saved register for m68k so this would never show the issue.

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