[llvm] [AMDGPU][True16][Codegen] remove packed build_vector pattern from true16 (PR #148715)

[Brox Chen via llvm-commits]

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@@ -4007,6 +4007,8 @@ define amdgpu_ps <2 x half> @global_load_saddr_i16_d16lo_zero_hi(ptr addrspace(1
 ; GFX12-GISEL-TRUE16-NEXT:    global_load_d16_b16 v0, v0, s[2:3]
 ; GFX12-GISEL-TRUE16-NEXT:    s_wait_loadcnt 0x0
 ; GFX12-GISEL-TRUE16-NEXT:    v_and_b32_e32 v0, 0xffff, v0
+; GFX12-GISEL-TRUE16-NEXT:    s_delay_alu instid0(VALU_DEP_1)
+; GFX12-GISEL-TRUE16-NEXT:    v_lshl_or_b32 v0, 0, 16, v0
 ; GFX12-GISEL-TRUE16-NEXT:    ; return to shader part epilog
 ;
 ; GFX12-GISEL-FAKE16-LABEL: global_load_saddr_i16_d16lo_zero_hi:
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broxigarchen wrote:

Regarding using non-d16 forms when load and zext, I remember there should be patterns. Let me take a look

https://github.com/llvm/llvm-project/pull/148715