Change all ARM calls into indirect calls.

tests_lit/assembler/arm32/call.ll

+; Show that we convert direct calls, into indirect calls (to handle far
+;  branches).
+
+; NOTE: We use -O2 to get rid of memory stores.
+
+; REQUIRES: allow_dump
+
+; Compile using standalone assembler.
+; RUN: %p2i --filetype=asm -i %s --target=arm32 --args -O2 -allow-extern \
+; RUN:   -reg-use r5 | FileCheck %s --check-prefix=ASM
+
+; Show bytes in assembled standalone code.
+; RUN: %p2i --filetype=asm -i %s --target=arm32 --assemble --disassemble \
+; RUN:   --args -O2 -allow-extern -reg-use r5 | FileCheck %s --check-prefix=DIS
+
+; Compile using integrated assembler.
+; RUN: %p2i --filetype=iasm -i %s --target=arm32 --args -O2 \
+; RUN:   -allow-extern -reg-use r5 | FileCheck %s --check-prefix=IASM
+
+; Show bytes in assembled integrated code.
+; RUN: %p2i --filetype=iasm -i %s --target=arm32 --assemble --disassemble \
+; RUN:   --args -O2 -allow-extern -reg-use r5 | FileCheck %s --check-prefix=DIS
+
+declare external void @doSomething()
+
+define internal void @callSomething() {
+; ASM-LABEL:callSomething:
+; DIS-LABEL:{{.+}} <callSomething>:
+; IASM-LABEL:callSomething:
+
+  call void @doSomething();
+
+; ASM:      movw        r5, #:lower16:doSomething
+; DIS:      {{.+}}:     e3005000
+; ASM-NOT:  movw
+
+; ASM-NEXT: movt        r5, #:upper16:doSomething
+; DIS-NEXT: {{.+}}:     e3405000
+; ASM-NOT:  movt
+
+; ASM-NEXT: blx r5
+; DIS-NEXT: {{.+}}:     e12fff35
+; ASM-NOT:  blx
+  ret void
+}