[llvm] [LegalizeTypes] Create an ISD::ADD instead of an ISD::UADDO with unused overflow result. (PR #100647)

[Matt Arsenault via llvm-commits]

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@@ -115,7 +115,7 @@ define i128 @knownbits_mask_addc_shl(i64 %a0, i64 %a1, i64 %a2) nounwind {
 ; X64-NEXT:    andq $-1024, %rdi # imm = 0xFC00
 ; X64-NEXT:    andq $-1024, %rsi # imm = 0xFC00
 ; X64-NEXT:    addq %rdi, %rsi
-; X64-NEXT:    adcq $0, %rdx
+; X64-NEXT:    adcl $0, %edx
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arsenm wrote:

I'm surprised this wasn't already cleaned up by a combine later 

https://github.com/llvm/llvm-project/pull/100647