[llvm] [AMDGPU] Fix BITOP3 matcher for op(X, X) operands (PR #198373)

[Arseniy Obolenskiy via llvm-commits]

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@@ -741,6 +741,221 @@ define amdgpu_ps half @test_and_or_b16(i16 %a, i16 %b, i16 %c) {
   %ret_cast = bitcast i16 %or1 to half
   ret half %ret_cast
 }
+; ========= op(X, X) — verify the BITOP3 matcher does not corrupt cached
+; truth-table bits when both operands of an AND/OR/XOR share the same Src
+; slot. The `optnone` attribute keeps the self-op alive through DAGCombine
+; so selection actually sees the LHS == RHS shape.
+
+define i32 @xor_self_complex(i32 %a, i32 %b, i32 %c) #0 {
+; GFX950-SDAG-LABEL: xor_self_complex:
+; GFX950-SDAG:       ; %bb.0:
+; GFX950-SDAG-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX950-SDAG-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX950-SDAG-NEXT:    v_xor_b32_e64 v0, v0, v0
+; GFX950-SDAG-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX950-GISEL-LABEL: xor_self_complex:
+; GFX950-GISEL:       ; %bb.0:
+; GFX950-GISEL-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX950-GISEL-NEXT:    s_mov_b32 s0, 0
+; GFX950-GISEL-NEXT:    v_mov_b32_e32 v0, s0
+; GFX950-GISEL-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX1250-SDAG-LABEL: xor_self_complex:
+; GFX1250-SDAG:       ; %bb.0:
+; GFX1250-SDAG-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-SDAG-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-SDAG-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX1250-SDAG-NEXT:    v_xor_b32_e64 v0, v0, v0
+; GFX1250-SDAG-NEXT:    s_set_pc_i64 s[30:31]
+;
+; GFX1250-GISEL-LABEL: xor_self_complex:
+; GFX1250-GISEL:       ; %bb.0:
+; GFX1250-GISEL-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-GISEL-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-GISEL-NEXT:    s_mov_b32 s0, 0
+; GFX1250-GISEL-NEXT:    v_mov_b32_e32 v0, s0
+; GFX1250-GISEL-NEXT:    s_set_pc_i64 s[30:31]
+  %t1 = and i32 %a, %b
+  %xor1 = xor i32 %t1, %c
+  %res = xor i32 %xor1, %xor1
+  ret i32 %res
+}
+
+define i32 @and_self_complex(i32 %a, i32 %b, i32 %c) #0 {
+; GFX950-SDAG-LABEL: and_self_complex:
+; GFX950-SDAG:       ; %bb.0:
+; GFX950-SDAG-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX950-SDAG-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX950-SDAG-NEXT:    v_and_b32_e64 v0, v0, v0
+; GFX950-SDAG-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX950-GISEL-LABEL: and_self_complex:
+; GFX950-GISEL:       ; %bb.0:
+; GFX950-GISEL-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX950-GISEL-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX950-GISEL-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX1250-SDAG-LABEL: and_self_complex:
+; GFX1250-SDAG:       ; %bb.0:
+; GFX1250-SDAG-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-SDAG-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-SDAG-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX1250-SDAG-NEXT:    v_and_b32_e64 v0, v0, v0
+; GFX1250-SDAG-NEXT:    s_set_pc_i64 s[30:31]
+;
+; GFX1250-GISEL-LABEL: and_self_complex:
+; GFX1250-GISEL:       ; %bb.0:
+; GFX1250-GISEL-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-GISEL-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-GISEL-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX1250-GISEL-NEXT:    s_set_pc_i64 s[30:31]
+  %t1 = and i32 %a, %b
+  %xor1 = xor i32 %t1, %c
+  %res = and i32 %xor1, %xor1
+  ret i32 %res
+}
+
+define i32 @or_self_complex(i32 %a, i32 %b, i32 %c) #0 {
+; GFX950-SDAG-LABEL: or_self_complex:
+; GFX950-SDAG:       ; %bb.0:
+; GFX950-SDAG-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX950-SDAG-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX950-SDAG-NEXT:    v_or_b32_e64 v0, v0, v0
+; GFX950-SDAG-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX950-GISEL-LABEL: or_self_complex:
+; GFX950-GISEL:       ; %bb.0:
+; GFX950-GISEL-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GFX950-GISEL-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX950-GISEL-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX1250-SDAG-LABEL: or_self_complex:
+; GFX1250-SDAG:       ; %bb.0:
+; GFX1250-SDAG-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-SDAG-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-SDAG-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX1250-SDAG-NEXT:    v_or_b32_e64 v0, v0, v0
+; GFX1250-SDAG-NEXT:    s_set_pc_i64 s[30:31]
+;
+; GFX1250-GISEL-LABEL: or_self_complex:
+; GFX1250-GISEL:       ; %bb.0:
+; GFX1250-GISEL-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-GISEL-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-GISEL-NEXT:    v_bitop3_b32 v0, v0, v2, v1 bitop3:0x6c
+; GFX1250-GISEL-NEXT:    s_set_pc_i64 s[30:31]
+  %t1 = and i32 %a, %b
+  %xor1 = xor i32 %t1, %c
+  %res = or i32 %xor1, %xor1
+  ret i32 %res
+}
+
+define i32 @xor_self_complex_noundef(i32 noundef %a, i32 noundef %b, i32 noundef %c) #0 {
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aobolensk wrote:

@arsenm could you please check?

https://github.com/llvm/llvm-project/pull/198373