ARM: Remove fake entries for divrem libcalls (#143832)

This was defining aliases of the i32 divrem functions for the i8
and i16 cases. This is unnecessary and was unused. The divrem
candidate cases wouldn't have formed with illegal types in the
first place, so codegen wouldn't even query these.

Author: arsenm

llvm/lib/IR/RuntimeLibcalls.cpp

@@ -41,13 +41,8 @@ static void setARMLibcallNames(RuntimeLibcallsInfo &Info, const Triple &TT) {
         const char *const Name;
         const CallingConv::ID CC;
       } LibraryCalls[] = {
-          {RTLIB::SDIVREM_I8, "__rt_sdiv", CallingConv::ARM_AAPCS},
-          {RTLIB::SDIVREM_I16, "__rt_sdiv", CallingConv::ARM_AAPCS},
           {RTLIB::SDIVREM_I32, "__rt_sdiv", CallingConv::ARM_AAPCS},
           {RTLIB::SDIVREM_I64, "__rt_sdiv64", CallingConv::ARM_AAPCS},
-
-          {RTLIB::UDIVREM_I8, "__rt_udiv", CallingConv::ARM_AAPCS},
-          {RTLIB::UDIVREM_I16, "__rt_udiv", CallingConv::ARM_AAPCS},
           {RTLIB::UDIVREM_I32, "__rt_udiv", CallingConv::ARM_AAPCS},
           {RTLIB::UDIVREM_I64, "__rt_udiv64", CallingConv::ARM_AAPCS},
       };
@@ -62,13 +57,8 @@ static void setARMLibcallNames(RuntimeLibcallsInfo &Info, const Triple &TT) {
         const char *const Name;
         const CallingConv::ID CC;
       } LibraryCalls[] = {
-          {RTLIB::SDIVREM_I8, "__aeabi_idivmod", CallingConv::ARM_AAPCS},
-          {RTLIB::SDIVREM_I16, "__aeabi_idivmod", CallingConv::ARM_AAPCS},
           {RTLIB::SDIVREM_I32, "__aeabi_idivmod", CallingConv::ARM_AAPCS},
           {RTLIB::SDIVREM_I64, "__aeabi_ldivmod", CallingConv::ARM_AAPCS},
-
-          {RTLIB::UDIVREM_I8, "__aeabi_uidivmod", CallingConv::ARM_AAPCS},
-          {RTLIB::UDIVREM_I16, "__aeabi_uidivmod", CallingConv::ARM_AAPCS},
           {RTLIB::UDIVREM_I32, "__aeabi_uidivmod", CallingConv::ARM_AAPCS},
           {RTLIB::UDIVREM_I64, "__aeabi_uldivmod", CallingConv::ARM_AAPCS},
       };