[llvm] [GlobalISel] Fix buildCopyFromRegs for split vectors (PR #77448)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,96 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -global-isel -mtriple=amdgcn | FileCheck %s -check-prefixes=GCN
+; RUN: llc < %s -global-isel -mtriple=amdgcn -mcpu=hawaii | FileCheck %s -check-prefixes=GFX7
+; RUN: llc < %s -global-isel -mtriple=amdgcn -mcpu=tonga | FileCheck %s -check-prefixes=GFX8
+; RUN: llc < %s -global-isel -mtriple=amdgcn -mcpu=gfx900 | FileCheck %s -check-prefixes=GFX9
+; RUN: llc < %s -global-isel -mtriple=amdgcn -mcpu=gfx1010 | FileCheck %s -check-prefixes=GFX10
+; RUN: llc < %s -global-isel -mtriple=amdgcn -mcpu=gfx1100 -mattr=+real-true16 | FileCheck %s -check-prefix=GFX11
+; RUN: llc < %s -global-isel -mtriple=amdgcn -mcpu=gfx1100 -mattr=-real-true16 | FileCheck %s -check-prefix=GFX11
+
+; TODO: expand testcases - currently only contains cases that were known to crash.
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arsenm wrote:

it was essentially every bfloat vector. Should just test all the usual vector sizes 

https://github.com/llvm/llvm-project/pull/77448