[DebugInfo][InstrRef] "final final" test cleanups for x86 tests

[jmorse]

Summary

Two "totally definitely the last ones" test updates:

• fp-stack.ll: this test targets i686, and so it won't be getting instruction referencing, or at least not right now,
• X86/live-debug-values.ll: instruction referencing will produce entry values in this test, add check lines to account for this. It's not clear what the test is supposed to be testing anyway, but the entry values appear to be correct.

[Orlando]

LGTM

llvm/test/DebugInfo/COFF/fp-stack.ll

-; RUN: llc -mtriple=i686-windows-msvc < %s -experimental-debug-variable-locations=false | FileCheck %s --check-prefix=ASM
-; RUN: llc -mtriple=i686-windows-msvc < %s -filetype=obj -experimental-debug-variable-locations=false | llvm-readobj --codeview - | FileCheck %s --check-prefix=OBJ
+; RUN: llc -mtriple=i686-windows-msvc < %s | FileCheck %s --check-prefix=ASM
+; RUN: llc -mtriple=i686-windows-msvc < %s -filetype=obj | llvm-readobj --codeview - | FileCheck %s --check-prefix=OBJ
 target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
 target triple = "i686-pc-windows-msvc18.0.0"
 
 define double @f(double %p1) !dbg !4 {
 entry:
   %sub = fsub double -0.000000e+00, %p1, !dbg !16
   tail call void @llvm.dbg.value(metadata double %sub, metadata !10, metadata !14), !dbg !15
   ret double %sub

llvm/test/DebugInfo/X86/live-debug-values.ll

 ; RUN: llc -filetype=asm %s -o - -experimental-debug-variable-locations=false | FileCheck %s
+; RUN: llc -filetype=asm %s -o - -experimental-debug-variable-locations=true | FileCheck %s --check-prefixes=CHECK,INSTRREF
 
 ; Test the extension of debug ranges from predecessors.
 ; Generated from the source file LiveDebugValues.c:
 ; #include <stdio.h>
 ; int m;
 ; extern int inc(int n); 
 ; extern int change(int n); 
 ; extern int modify(int n); 

 ;   return 0;
 ; }
 ; with clang -g -O3 -emit-llvm -c LiveDebugValues.c -S -o live-debug-values.ll
 ; This case will also produce multiple locations but only the debug range
 ; extension is tested here.
 
 ; DBG_VALUE for variable "n" is extended into %bb.5 from its predecessors %bb.3
 ; and %bb.4.
-; CHECK:       .LBB0_5:
-; CHECK-NEXT:  #DEBUG_VALUE: main:n <- $ebx
+; CHECK:         .LBB0_5:
+; INSTRREF-NEXT: #DEBUG_VALUE: main:argc <- [DW_OP_LLVM_entry_value 1] $edi
+; INSTRREF-NEXT: #DEBUG_VALUE: main:argv <- [DW_OP_LLVM_entry_value 1] $rsi
+; CHECK-NEXT:    #DEBUG_VALUE: main:n <- $ebx
 ;   Other register values have been clobbered.
 ; CHECK-NOT:   #DEBUG_VALUE:
 ; CHECK:         movl    %e{{..}}, m(%rip)
 
 ; ModuleID = 'LiveDebugValues.c'
 source_filename = "test/DebugInfo/X86/live-debug-values.ll"
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"