[HotColdSplit] Add test case for unlikely attribute in outlined function

[hiraditya]

Summary

Recommitting D69384 to run only for x86 targets.

[hiraditya]

The ARM build bots do not compile this target as part of their build, causing this test to abort when '-codegenprepare' is added without any REQUIRES clause.

llvm/test/Transforms/HotColdSplit/coldentrycount.ll

+; REQUIRES: x86-registered-target
+; RUN: opt -hotcoldsplit -hotcoldsplit-threshold=0 -codegenprepare -S < %s | FileCheck %s
+
 ; Test to ensure that split cold function gets 0 entry count profile
 ; metadata when compiling with pgo.
 
-; RUN: opt -hotcoldsplit -hotcoldsplit-threshold=0 -S < %s | FileCheck %s
-
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.14.0"
 
-; CHECK-LABEL: @fun
+; CHECK: define {{.*}} @fun{{.*}} ![[HOTPROF:[0-9]+]] {{.*}}section_prefix ![[LIKELY:[0-9]+]]
 ; CHECK: call void @fun.cold.1
+
 define void @fun() !prof !14 {
 entry:
   br i1 undef, label %if.then, label %if.else
 
 if.then:
   ret void
 
 if.else:
   call void @sink()
   ret void
 }
 
 declare void @sink() cold
 
-; CHECK: define {{.*}} @fun.cold.1{{.*}} ![[PROF:[0-9]+]]
+; CHECK: define {{.*}} @fun.cold.1{{.*}} ![[PROF:[0-9]+]] {{.*}}section_prefix ![[UNLIKELY:[0-9]+]]
+
+; CHECK: ![[HOTPROF]] = !{!"function_entry_count", i64 100}
+; CHECK: ![[LIKELY]] = !{!"function_section_prefix", !".hot"}
 ; CHECK: ![[PROF]] = !{!"function_entry_count", i64 0}
+; CHECK: ![[UNLIKELY]] = !{!"function_section_prefix", !".unlikely"}
 
 !llvm.module.flags = !{!0}
 !0 = !{i32 1, !"ProfileSummary", !1}
 !1 = !{!2, !3, !4, !5, !6, !7, !8, !9}
 !2 = !{!"ProfileFormat", !"InstrProf"}
 !3 = !{!"TotalCount", i64 10000}
 !4 = !{!"MaxCount", i64 10}
 !5 = !{!"MaxInternalCount", i64 1}
 !6 = !{!"MaxFunctionCount", i64 1000}
 !7 = !{!"NumCounts", i64 3}
 !8 = !{!"NumFunctions", i64 3}
 !9 = !{!"DetailedSummary", !10}
 !10 = !{!11, !12, !13}
 !11 = !{i32 10000, i64 100, i32 1}
 !12 = !{i32 999000, i64 100, i32 1}
 !13 = !{i32 999999, i64 1, i32 2}
 !14 = !{!"function_entry_count", i64 100}
+!15 = !{!"function_section_prefix", !".hot"}
+!16 = !{!"function_entry_count", i64 0}
+!17 = !{!"function_section_prefix", !".unlikely"}