[llvm] [Codegen][LegalizeIntegerTypes] Improve shift through stack (PR #96151)

[Matt Arsenault via llvm-commits]

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@@ -179,21 +179,36 @@ define void @ashr_16bytes(ptr %src.ptr, ptr %byteOff.ptr, ptr %dst) nounwind {
 define void @lshr_32bytes(ptr %src.ptr, ptr %byteOff.ptr, ptr %dst) nounwind {
 ; ALL-LABEL: lshr_32bytes:
 ; ALL:       // %bb.0:
-; ALL-NEXT:    sub sp, sp, #64
-; ALL-NEXT:    ldp x9, x8, [x0, #16]
-; ALL-NEXT:    movi v0.2d, #0000000000000000
+; ALL-NEXT:    ldr q0, [x0]
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arsenm wrote:

The AArch64 result looks much worse 

https://github.com/llvm/llvm-project/pull/96151