Rewrite some tests with FileCHeck in X86 codegen

- Revise previous patches of the same purpose by fixing
  *) grep <PA> | not grep <PB> semantically is not the same as
     CHECK: <PA>{{^<PB>.*$}} as the former will check all occurrences of <PA>
     while the later only check the first match. As the result, CHECK needs
     putting in all place where <PA> occurs.
  *) grep <PA> | count <N> needs a final CHECK-NOT of the same pattern.
     (As 'CHECK-<N>' is proposed for discussion, converting 'grep | count <N>'
      where N > 1 is postponed.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180742 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/X86/fastcc3struct.ll

@@ -1,5 +1,5 @@
-; RUN: llc < %s -march=x86 -o %t
-; RUN: FileCheck %s -input-file %t
+; RUN: llc < %s -march=x86 | FileCheck %s
+
 ; CHECK: movl {{.}}12, %eax
 ; CHECK: movl {{.}}24, %edx
 ; CHECK: movl {{.}}48, %ecx