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

tests_lit/llvm2ice_tests/nop-insertion.ll

 ; This is a smoke test of nop insertion.
 
 ; REQUIRES: allow_dump
 
 ; Use filetype=asm because this currently depends on the # variant
 ; assembler comment.
 
 ; RUN: %p2i -i %s --filetype=asm -a -sz-seed=1 -nop-insertion \
 ; RUN:    -nop-insertion-percentage=50 -max-nops-per-instruction=1 \
 ; RUN:    | FileCheck %s --check-prefix=PROB50
 ; RUN: %p2i -i %s --filetype=asm -a -sz-seed=1 -nop-insertion \
 ; RUN:    -nop-insertion-percentage=90 -max-nops-per-instruction=1 \
 ; RUN:    | FileCheck %s --check-prefix=PROB90
 ; RUN: %p2i -i %s --filetype=asm -a -sz-seed=1 -nop-insertion \
 ; RUN:    -nop-insertion-percentage=50 -max-nops-per-instruction=2 \
 ; RUN:    | FileCheck %s --check-prefix=MAXNOPS2
 ; RUN: %p2i -i %s --filetype=asm -a -sz-seed=1 -nop-insertion -sandbox\
 ; RUN:    -nop-insertion-percentage=50 -max-nops-per-instruction=1 \
 ; RUN:    | FileCheck %s --check-prefix=SANDBOX50
 
 
-define <4 x i32> @mul_v4i32(<4 x i32> %a, <4 x i32> %b) {
+define internal <4 x i32> @mul_v4i32(<4 x i32> %a, <4 x i32> %b) {
 entry:
   %res = mul <4 x i32> %a, %b
   ret <4 x i32> %res
 
 ; PROB50-LABEL: mul_v4i32
 ; PROB50: nop # variant = 1
 ; PROB50: subl $60, %esp
 ; PROB50: nop # variant = 3
 ; PROB50: movups %xmm0, 32(%esp)
 ; PROB50: movups %xmm1, 16(%esp)
@@ skipping 98 matching lines @@
 ; SANDBOX50: movups %xmm0, (%esp)
 ; SANDBOX50: movups (%esp), %xmm0
 ; SANDBOX50: addl $60, %esp
 ; SANDBOX50: pop %ecx
 ; SANDBOX50: .bundle_lock
 ; SANDBOX50: andl $-32, %ecx
 ; SANDBOX50: jmp *%ecx
 ; SANDBOX50: .bundle_unlock
 
 }