[llvm] [DAGCombiner] `visitSIGN_EXTEND_INREG` - fold `(sext_inreg (freeze (extload x)))` -> `(freeze (sextload x))` (PR #226208)

[via llvm-commits]

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@@ -37,9 +37,9 @@ define i8 @test_i8(i8 %a) nounwind {
 define i16 @test_i16(i16 %a) nounwind {
 ; X86-NO-CMOV-LABEL: test_i16:
 ; X86-NO-CMOV:       # %bb.0:
-; X86-NO-CMOV-NEXT:    movl {{[0-9]+}}(%esp), %eax
-; X86-NO-CMOV-NEXT:    movswl %ax, %ecx
-; X86-NO-CMOV-NEXT:    sarl $15, %ecx
+; X86-NO-CMOV-NEXT:    movswl {{[0-9]+}}(%esp), %eax
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VachanVY wrote:

regression? another ext(freeze(load)) :/ ?

https://github.com/llvm/llvm-project/pull/226208