[llvm] [AMDGPU] Add intrinsics and MIs for ds_bvh_stack_* (PR #130007)

[Jay Foad via llvm-commits]

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@@ -1929,6 +1929,12 @@ ds_bvh_stack_push4_pop1_rtn_b32 v1, v0, v1, v[2:5]
 ds_bvh_stack_push4_pop1_rtn_b32 v1, v0, v1, v[2:5] offset:1
 // GFX12: encoding: [0x01,0x00,0x80,0xdb,0x00,0x01,0x02,0x01]
 
+ds_bvh_stack_rtn_b32 v1, v0, v1, v[2:5]
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jayfoad wrote:

Nit:should really be in gfx12_asm_ds**_alias**.s and you only need one example of the instruction.

https://github.com/llvm/llvm-project/pull/130007