Make sure that all globals are internal, except for "start" functions.

tests_lit/llvm2ice_tests/large_stack_offs.ll

 ; This tries to create variables with very large stack offsets.
 ; This requires a lot of variables/register pressure. To simplify this
 ; we assume poor register allocation from Om1, and a flag that forces
 ; the frame to add K amount of unused stack for testing.
 ; We only need to test ARM and other architectures which have limited space
 ; for specifying an offset within an instruction.
 
 ; RUN: %if --need=target_ARM32 --need=allow_dump \
 ; RUN:   --command %p2i --filetype=asm --assemble --disassemble --target arm32 \
 ; RUN:   -i %s --args -Om1 --skip-unimplemented --test-stack-extra 4096 \
+; RUN:   -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_ARM32 --need=allow_dump \
 ; RUN:   --command FileCheck --check-prefix ARM32 %s
 
 declare i64 @dummy(i32 %t1, i32 %t2, i32 %t3, i64 %t4, i64 %t5)
 
 ; Test a function that requires lots of stack (due to test flag), and uses
 ; SP as the base register (originally).
 define internal i64 @lotsOfStack(i32 %a, i32 %b, i32 %c, i32 %d) {
 entry:
   %t1 = xor i32 %a, %b
@@ skipping 103 matching lines @@
 ; ARM32: sub sp, sp, #16
 ; Now sp1 = sp0 - 16, but ip is still in terms of fp0.
 ; So, fp0 - 4124 == ip - 4.
 ; ARM32: ldr r2, [ip, #-4]
 ; ARM32: bl {{.*}} dummy
 ; ARM32: add sp, sp
 ; The call clobbers ip, so we need to re-create the base register.
 ; ARM32: movw ip, #4{{.*}}
 ; ARM32: b {{[a-f0-9]+}}
 ; ARM32: bl {{.*}} dummy