[llvm] [DAG] Reducing instructions by better legalization handling of AVGFLOORU for illegal data types (PR #99913)

[Craig Topper via llvm-commits]

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@@ -164,18 +164,20 @@ define i32 @test_ext_i32(i32 %a0, i32 %a1) nounwind {
 define i64 @test_fixed_i64(i64 %a0, i64 %a1) nounwind {
 ; RV32I-LABEL: test_fixed_i64:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    and a4, a1, a3
-; RV32I-NEXT:    xor a1, a1, a3
-; RV32I-NEXT:    srli a3, a1, 1
-; RV32I-NEXT:    add a3, a4, a3
-; RV32I-NEXT:    slli a1, a1, 31
-; RV32I-NEXT:    xor a4, a0, a2
-; RV32I-NEXT:    srli a4, a4, 1
-; RV32I-NEXT:    or a1, a4, a1
-; RV32I-NEXT:    and a2, a0, a2
-; RV32I-NEXT:    add a0, a2, a1
+; RV32I-NEXT:    add a4, a3, a1
+; RV32I-NEXT:    add a0, a2, a0
 ; RV32I-NEXT:    sltu a1, a0, a2
-; RV32I-NEXT:    add a1, a3, a1
+; RV32I-NEXT:    add a2, a4, a1
+; RV32I-NEXT:    beq a2, a3, .LBB6_2
+; RV32I-NEXT:  # %bb.1:
+; RV32I-NEXT:    sltu a1, a2, a3
+; RV32I-NEXT:  .LBB6_2:
+; RV32I-NEXT:    slli a1, a1, 31
+; RV32I-NEXT:    srli a3, a2, 1
+; RV32I-NEXT:    or a1, a3, a1
+; RV32I-NEXT:    slli a2, a2, 31
+; RV32I-NEXT:    srli a0, a0, 1
+; RV32I-NEXT:    or a0, a0, a2
 ; RV32I-NEXT:    ret
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topperc wrote:

The instruction count is actually the same. The 2 extra lines are labels. Not sure about the path length though.

https://github.com/llvm/llvm-project/pull/99913