[llvm] [AArch64][GlobalISel] Use GPR for illegal fconstants and extend < 32 bit GPR constants to 32 bits (PR #178692)

[Cullen Rhodes via llvm-commits]

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@@ -1,5 +1,5 @@
 # NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
-# RUN: llc -verify-machineinstrs -mtriple aarch64--- -run-pass=instruction-select -global-isel-abort=1 %s -o - | FileCheck %s
+# RUN: llc -verify-machineinstrs -mtriple aarch64--- --run-pass=regbankselect --run-pass=instruction-select -global-isel-abort=1 %s -o - | FileCheck %s
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c-rhodes wrote:

`-run-pass` takes a comma-separated list

although I know GISel testing is a bit different so i wonder if the input should instead be re-generated from running regbankselect to keep it to a single pass

https://github.com/llvm/llvm-project/pull/178692