[PATCH] Ensure that TCReturn instructions are resolved

[Tim Northover]

Thanks for updating the test. It's usually better to test the actual output rather than just that a function doesn't crash though. 

I'd suggest something like (untested):

    ; RUN: llc -mtriple=thumbv7-eabi -o - %s | FileCheck %s
    
    declare cc 10 void @g()
    
    define cc 10 void @test_direct_tail() {
    ; CHECK-LABEL: test_direct_tail:
    ; CHECK: b g
    
      tail call cc10 void @g()
      ret void
    }
    
    @ind_func = global void()* zeroinitializer
    
    define cc 10 void @test_indirect_tail() {
    ; CHECK-LABEL: test_indirect_tail:
    ; CHECK: b {{r[0-9]+}}
      %func = load void()** @ind_func
      tail call cc10 void()* @%func()
      ret void
    }

This also avoids leaving a stray .s file in the source directory and tests both TCRETURNdi and TCRETURNri.

http://reviews.llvm.org/D6445