[llvm] AMDGPU: Add baseline tests for bitcast + readlane intrinsics (PR #128493)

[Pravin Jagtap via llvm-commits]

================
@@ -0,0 +1,271 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1010 -passes=instcombine -S < %s | FileCheck %s
+
+define i32 @test_bitcast_f32_to_i32_readfirstlane(float %val) {
----------------
pravinjagtap wrote:

how about adding negative tests for div value ?

https://github.com/llvm/llvm-project/pull/128493