[llvm] [DAGCombine] Propagate truncate to operands (PR #98666)

[Matt Arsenault via llvm-commits]

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@@ -176,11 +176,13 @@ define amdgpu_kernel void @s_and_i64(ptr addrspace(1) %out, i64 %a, i64 %b) {
 
 ; FUNC-LABEL: {{^}}s_and_i1:
 ; SI: s_load_dword [[LOAD:s[0-9]+]]
-; SI: s_lshr_b32 [[B_SHIFT:s[0-9]+]], [[LOAD]], 8
-; SI: s_and_b32 [[AND:s[0-9]+]], [[LOAD]], [[B_SHIFT]]
-; SI: s_and_b32 [[AND_TRUNC:s[0-9]+]], [[AND]], 1{{$}}
-; SI: v_mov_b32_e32 [[V_AND_TRUNC:v[0-9]+]], [[AND_TRUNC]]
-; SI: buffer_store_byte [[V_AND_TRUNC]]
+; SI: s_bitcmp1_b32 [[LOAD]], 0
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arsenm wrote:

This is worse (i1 is difficult) 

https://github.com/llvm/llvm-project/pull/98666