[llvm] [AArch64][GlobalISel] Add push_mul_through_s/zext (PR #141551)

[Cullen Rhodes via llvm-commits]

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@@ -553,14 +580,14 @@ void applyExtUaddvToUaddlv(MachineInstr &MI, MachineRegisterInfo &MRI,
   MI.eraseFromParent();
 }
 
-// Pushes ADD/SUB through extend instructions to decrease the number of extend
-// instruction at the end by allowing selection of {s|u}addl sooner
-
-// i32 add(i32 ext i8, i32 ext i8) => i32 ext(i16 add(i16 ext i8, i16 ext i8))
+// Pushes ADD/SUB/MUL through extend instructions to decrease the number of
+// extend instruction at the end by allowing selection of {s|u}addl sooner i32
+// add(i32 ext i8, i32 ext i8) => i32 ext(i16 add(i16 ext i8, i16 ext i8))
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c-rhodes wrote:

I think you've accidentally merged these two comments

https://github.com/llvm/llvm-project/pull/141551