[llvm] AMDGPU/GlobalISel: Add regbanklegalize rules for uniform global loads (PR #145909)

[Petar Avramovic via llvm-commits]

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@@ -0,0 +1,95 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -global-isel -new-reg-bank-select -mtriple=amdgcn-amd-amdpal -mcpu=gfx1010 -verify-machineinstrs < %s | FileCheck %s
+
+define amdgpu_ps void @uniform_load_32(ptr addrspace(1) inreg %ptr0, ptr addrspace(1) inreg %ptr1, ptr addrspace(1) inreg %ptr2) {
+; CHECK-LABEL: uniform_load_32:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    global_load_dword v1, v0, s[0:1] glc dlc
+; CHECK-NEXT:    s_waitcnt vmcnt(0)
+; CHECK-NEXT:    global_load_dword v2, v0, s[2:3] glc dlc
+; CHECK-NEXT:    s_waitcnt vmcnt(0)
+; CHECK-NEXT:    v_readfirstlane_b32 s0, v1
+; CHECK-NEXT:    v_readfirstlane_b32 s1, v2
+; CHECK-NEXT:    s_add_i32 s0, s0, s1
+; CHECK-NEXT:    v_mov_b32_e32 v1, s0
+; CHECK-NEXT:    global_store_dword v0, v1, s[4:5]
+; CHECK-NEXT:    s_endpgm
+  %load0 = load volatile i32, ptr addrspace(1) %ptr0
+  %load1 = load volatile i32, ptr addrspace(1) %ptr1
+  %sum = add i32 %load0, %load1
+  store i32 %sum, ptr addrspace(1) %ptr2
+  ret void
+}
+
+define amdgpu_ps void @uniform_load_64(ptr addrspace(1) inreg %ptr0, ptr addrspace(1) inreg %ptr1) {
+; CHECK-LABEL: uniform_load_64:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    global_load_dwordx2 v[0:1], v2, s[0:1] glc dlc
+; CHECK-NEXT:    s_waitcnt vmcnt(0)
+; CHECK-NEXT:    v_readfirstlane_b32 s0, v0
+; CHECK-NEXT:    v_readfirstlane_b32 s1, v1
+; CHECK-NEXT:    s_add_i32 s0, s0, s1
+; CHECK-NEXT:    v_mov_b32_e32 v0, s0
+; CHECK-NEXT:    global_store_dword v2, v0, s[2:3]
+; CHECK-NEXT:    s_endpgm
+  %load = load volatile <2 x i32>, ptr addrspace(1) %ptr0
+  %elt0 = extractelement <2 x i32> %load, i32 0
+  %elt1 = extractelement <2 x i32> %load, i32 1
+  %sum = add i32 %elt0, %elt1
+  store i32 %sum, ptr addrspace(1) %ptr1
+  ret void
+}
+
+define amdgpu_ps void @uniform_load_96(ptr addrspace(1) inreg %ptr0, ptr addrspace(1) inreg %ptr1) {
+; CHECK-LABEL: uniform_load_96:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    v_mov_b32_e32 v3, 0
+; CHECK-NEXT:    global_load_dwordx3 v[0:2], v3, s[0:1] glc dlc
+; CHECK-NEXT:    s_waitcnt vmcnt(0)
+; CHECK-NEXT:    v_readfirstlane_b32 s0, v0
+; CHECK-NEXT:    v_readfirstlane_b32 s1, v1
+; CHECK-NEXT:    v_readfirstlane_b32 s4, v2
+; CHECK-NEXT:    s_add_i32 s0, s0, s1
+; CHECK-NEXT:    s_add_i32 s0, s0, s4
+; CHECK-NEXT:    v_mov_b32_e32 v0, s0
+; CHECK-NEXT:    global_store_dword v3, v0, s[2:3]
+; CHECK-NEXT:    s_endpgm
+  %load = load volatile <3 x i32>, ptr addrspace(1) %ptr0
+  %elt0 = extractelement <3 x i32> %load, i32 0
+  %elt1 = extractelement <3 x i32> %load, i32 1
+  %elt2 = extractelement <3 x i32> %load, i32 2
+  %sum0 = add i32 %elt0, %elt1
+  %sum = add i32 %sum0, %elt2
+  store i32 %sum, ptr addrspace(1) %ptr1
+  ret void
+}
+
+define amdgpu_ps void @uniform_load_128(ptr addrspace(1) inreg %ptr0, ptr addrspace(1) inreg %ptr1) {
+; CHECK-LABEL: uniform_load_128:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    v_mov_b32_e32 v4, 0
+; CHECK-NEXT:    global_load_dwordx4 v[0:3], v4, s[0:1] glc dlc
+; CHECK-NEXT:    s_waitcnt vmcnt(0)
+; CHECK-NEXT:    v_readfirstlane_b32 s0, v0
+; CHECK-NEXT:    v_readfirstlane_b32 s1, v1
+; CHECK-NEXT:    v_readfirstlane_b32 s4, v2
+; CHECK-NEXT:    v_readfirstlane_b32 s5, v3
+; CHECK-NEXT:    s_add_i32 s0, s0, s1
+; CHECK-NEXT:    s_add_i32 s0, s0, s4
+; CHECK-NEXT:    s_add_i32 s0, s0, s5
+; CHECK-NEXT:    v_mov_b32_e32 v0, s0
+; CHECK-NEXT:    global_store_dword v4, v0, s[2:3]
+; CHECK-NEXT:    s_endpgm
+  %load = load volatile <4 x i32>, ptr addrspace(1) %ptr0
+  %elt0 = extractelement <4 x i32> %load, i32 0
+  %elt1 = extractelement <4 x i32> %load, i32 1
+  %elt2 = extractelement <4 x i32> %load, i32 2
+  %elt3 = extractelement <4 x i32> %load, i32 3
+  %sum0 = add i32 %elt0, %elt1
+  %sum1 = add i32 %sum0, %elt2
+  %sum = add i32 %sum1, %elt3
+  store i32 %sum, ptr addrspace(1) %ptr1
+  ret void
+}
----------------
petar-avramovic wrote:

Not sure about this one. Align condition is from old regbankselect but maybe we don't need it, or it is wrong?
Legalizer deals with many cases of Align and splits load.
Do you know what we need to check for considering align? 

https://github.com/llvm/llvm-project/pull/145909