[clang] [llvm] [AMDGPU] Extend readlane, writelane and readfirstlane intrinsic lowering for generic types (PR #89217)

[Vikram Hegde via cfe-commits]

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@@ -0,0 +1,65 @@
+; RUN: llc -stop-after=amdgpu-isel -mtriple=amdgcn-- -mcpu=gfx1100 -verify-machineinstrs -o - %s | FileCheck --check-prefixes=CHECK,ISEL %s
+
+; CHECK-LABEL: name:            basic_readfirstlane_i64
+;       CHECK:    [[TOKEN:%[0-9]+]]{{[^ ]*}} = CONVERGENCECTRL_ANCHOR
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vikramRH wrote:

I currently see machine verifier failure which is not related to this patch. An  i32 example with trunc here, https://godbolt.org/z/he8asMe77. 
This is also seen with wider type legalizations that we do now, so I cannot integrate these with existing tests just yet. am I missing something here ?

https://github.com/llvm/llvm-project/pull/89217