diff --git a/clang/include/clang/Basic/CodeGenOptions.h b/clang/include/clang/Basic/CodeGenOptions.h
--- a/clang/include/clang/Basic/CodeGenOptions.h
+++ b/clang/include/clang/Basic/CodeGenOptions.h
@@ -346,6 +346,21 @@
   const char *Argv0 = nullptr;
   ArrayRef<const char *> CommandLineArgs;
 
+  /// The minimum hotness value a diagnostic needs in order to be included in
+  /// optimization diagnostics.
+  ///
+  /// The threshold is an Optional value, which maps to one of the 3 states:
+  /// 1. 0            => threshold disabled. All remarks will be printed.
+  /// 2. positive int => manual threshold by user. Remarks with hotness exceed
+  ///                    threshold will be printed.
+  /// 3. None         => 'auto' threshold by user. The actual value is not
+  ///                    available at command line, but will be synced with
+  ///                    hotness threshold from profile summary during
+  ///                    compilation.
+  ///
+  /// If threshold option is not specified, it is disabled by default.
+  Optional<uint64_t> DiagnosticsHotnessThreshold = 0;
+
 public:
   // Define accessors/mutators for code generation options of enumeration type.
 #define CODEGENOPT(Name, Bits, Default)
diff --git a/clang/include/clang/Basic/CodeGenOptions.def b/clang/include/clang/Basic/CodeGenOptions.def
--- a/clang/include/clang/Basic/CodeGenOptions.def
+++ b/clang/include/clang/Basic/CodeGenOptions.def
@@ -366,10 +366,6 @@
 /// Whether to report the hotness of the code region for optimization remarks.
 CODEGENOPT(DiagnosticsWithHotness, 1, 0)
 
-/// The minimum hotness value a diagnostic needs in order to be included in
-/// optimization diagnostics.
-VALUE_CODEGENOPT(DiagnosticsHotnessThreshold, 32, 0)
-
 /// Whether copy relocations support is available when building as PIE.
 CODEGENOPT(PIECopyRelocations, 1, 0)
 
diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -117,6 +117,8 @@
   "unable to execute command: %0">;
 def err_drv_invalid_darwin_version : Error<
   "invalid Darwin version number: %0">;
+def err_drv_invalid_diagnotics_hotness_threshold : Error<
+  "invalid argument in '%0', only integer or 'auto' is supported">;
 def err_drv_missing_argument : Error<
   "argument to '%0' is missing (expected %1 value%s1)">;
 def err_drv_invalid_Xarch_argument_with_args : Error<
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -984,8 +984,9 @@
 def fdiagnostics_show_hotness : Flag<["-"], "fdiagnostics-show-hotness">, Group<f_Group>,
     Flags<[CC1Option]>, HelpText<"Enable profile hotness information in diagnostic line">;
 def fdiagnostics_hotness_threshold_EQ : Joined<["-"], "fdiagnostics-hotness-threshold=">,
-    Group<f_Group>, Flags<[CC1Option]>, MetaVarName<"<number>">,
-    HelpText<"Prevent optimization remarks from being output if they do not have at least this profile count">;
+    Group<f_Group>, Flags<[CC1Option]>, MetaVarName<"<value>">,
+    HelpText<"Prevent optimization remarks from being output if they do not have at least this profile count. "
+    "Use 'auto' to apply the threshold from profile summary">;
 def fdiagnostics_show_option : Flag<["-"], "fdiagnostics-show-option">, Group<f_Group>,
     HelpText<"Print option name with mappable diagnostics">;
 def fdiagnostics_show_note_include_stack : Flag<["-"], "fdiagnostics-show-note-include-stack">,
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -14,6 +14,7 @@
 #include "clang/Basic/CommentOptions.h"
 #include "clang/Basic/DebugInfoOptions.h"
 #include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/DiagnosticDriver.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/FileSystemOptions.h"
 #include "clang/Basic/LLVM.h"
@@ -66,6 +67,7 @@
 #include "llvm/Option/OptTable.h"
 #include "llvm/Option/Option.h"
 #include "llvm/ProfileData/InstrProfReader.h"
+#include "llvm/Remarks/HotnessThresholdParser.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Error.h"
@@ -1501,11 +1503,24 @@
     Diags.Report(diag::warn_drv_diagnostics_hotness_requires_pgo)
         << "-fdiagnostics-show-hotness";
 
-  Opts.DiagnosticsHotnessThreshold = getLastArgUInt64Value(
-      Args, options::OPT_fdiagnostics_hotness_threshold_EQ, 0);
-  if (Opts.DiagnosticsHotnessThreshold > 0 && !UsingProfile)
-    Diags.Report(diag::warn_drv_diagnostics_hotness_requires_pgo)
-        << "-fdiagnostics-hotness-threshold=";
+  // Parse remarks hotness threshold. Valid value is either integer or 'auto'.
+  if (auto *arg =
+          Args.getLastArg(options::OPT_fdiagnostics_hotness_threshold_EQ)) {
+    auto ResultOrErr =
+        llvm::remarks::parseHotnessThresholdOption(arg->getValue());
+
+    if (!ResultOrErr) {
+      Diags.Report(diag::err_drv_invalid_diagnotics_hotness_threshold)
+          << "-fdiagnostics-hotness-threshold=";
+    } else {
+      Opts.DiagnosticsHotnessThreshold = *ResultOrErr;
+      if ((!Opts.DiagnosticsHotnessThreshold.hasValue() ||
+           Opts.DiagnosticsHotnessThreshold.getValue() > 0) &&
+          !UsingProfile)
+        Diags.Report(diag::warn_drv_diagnostics_hotness_requires_pgo)
+            << "-fdiagnostics-hotness-threshold=";
+    }
+  }
 
   // If the user requested to use a sample profile for PGO, then the
   // backend will need to track source location information so the profile
diff --git a/clang/test/Driver/opt-record.c b/clang/test/Driver/opt-record.c
--- a/clang/test/Driver/opt-record.c
+++ b/clang/test/Driver/opt-record.c
@@ -51,6 +51,7 @@
 // RUN: %clang -target x86_64-linux -### -o FOO -fuse-ld=gold -flto -fdiagnostics-hotness-threshold=100 -fsave-optimization-record -foptimization-record-passes=inline %s 2>&1 | FileCheck %s -check-prefix=CHECK-PASS
 // RUN: %clang -target x86_64-linux -### -o FOO -fuse-ld=lld -flto=thin -fdiagnostics-hotness-threshold=100 -fsave-optimization-record=some-format -foptimization-record-file=FOO.txt %s 2>&1 | FileCheck %s -check-prefix=CHECK-PASS-CUSTOM
 // RUN: %clang -target x86_64-linux -### -o FOO -fuse-ld=lld -flto=thin -fdiagnostics-hotness-threshold=100 -Rpass=inline -Rpass-missed=inline -Rpass-analysis=inline %s 2>&1 | FileCheck %s -check-prefix=CHECK-PASS-RPASS
+// RUN: %clang -target x86_64-linux -### -o FOO -fuse-ld=lld -flto=thin -fdiagnostics-hotness-threshold=auto -Rpass=inline -Rpass-missed=inline -Rpass-analysis=inline %s 2>&1 | FileCheck %s -check-prefix=CHECK-PASS-AUTO
 
 // CHECK-NOPASS-NOT: "--plugin-opt=opt-remarks-filename="
 // CHECK-NOPASS-NOT: "--plugin-opt=opt-remarks-passes=inline"
@@ -75,3 +76,5 @@
 // CHECK-PASS-RPASS-SAME: "--plugin-opt=-pass-remarks-missed=inline"
 // CHECK-PASS-RPASS-SAME: "--plugin-opt=-pass-remarks-analysis=inline"
 // CHECK-PASS-RPASS-SAME: "--plugin-opt=opt-remarks-hotness-threshold=100"
+
+// CHECK-PASS-AUTO:   "--plugin-opt=opt-remarks-hotness-threshold=auto"
diff --git a/clang/test/Frontend/Inputs/remarks-hotness.prof b/clang/test/Frontend/Inputs/remarks-hotness.prof
new file mode 100644
--- /dev/null
+++ b/clang/test/Frontend/Inputs/remarks-hotness.prof
@@ -0,0 +1,8 @@
+_Z7callee1v:600:600
+ 1: 600
+_Z7callee2v:1:1
+ 1: 1
+_Z7caller1v:400:400
+ 1: 400
+_Z7caller2v:1:1
+ 1: 1
diff --git a/clang/test/Frontend/remarks-hotness.cpp b/clang/test/Frontend/remarks-hotness.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/Frontend/remarks-hotness.cpp
@@ -0,0 +1,34 @@
+// Without hotness threshold, print both hot and cold remarks.
+// RUN: %clang_cc1 -triple x86_64-linux %s -emit-llvm-only -O3 \
+// RUN:     -fprofile-sample-use=%S/Inputs/remarks-hotness.prof \
+// RUN:     -Rpass=inline -Rpass-analysis=inline -Rpass-missed=inline \
+// RUN:     -fexperimental-new-pass-manager -fdiagnostics-show-hotness 2>&1 \
+// RUN:     | FileCheck -check-prefix=REMARKS %s
+
+// With auto hotness threshold, only print hot remarks.
+// RUN: %clang_cc1 -triple x86_64-linux %s -emit-llvm-only -O3 \
+// RUN:     -fprofile-sample-use=%S/Inputs/remarks-hotness.prof \
+// RUN:     -Rpass=inline -Rpass-analysis=inline -Rpass-missed=inline \
+// RUN:     -fexperimental-new-pass-manager -fdiagnostics-show-hotness \
+// RUN:     -fdiagnostics-hotness-threshold=auto 2>&1 \
+// RUN:     | FileCheck -check-prefix=HOT_CALL %s
+
+int callee1() {
+  return 1;
+}
+
+__attribute__((noinline)) int callee2() {
+  return 2;
+}
+
+// REMARKS: _Z7callee1v inlined into _Z7caller1v
+// HOT_CALL: _Z7callee1v inlined into _Z7caller1v
+int caller1() {
+  return callee1();
+}
+
+// REMARKS: _Z7callee2v not inlined into _Z7caller2v
+// HOT_CALL-NOT: _Z7callee2v not inlined into _Z7caller2v
+int caller2() {
+  return callee2();
+}
diff --git a/llvm/include/llvm/Analysis/ProfileSummaryInfo.h b/llvm/include/llvm/Analysis/ProfileSummaryInfo.h
--- a/llvm/include/llvm/Analysis/ProfileSummaryInfo.h
+++ b/llvm/include/llvm/Analysis/ProfileSummaryInfo.h
@@ -38,7 +38,7 @@
 // units. This would require making this depend on BFI.
 class ProfileSummaryInfo {
 private:
-  Module &M;
+  const Module &M;
   std::unique_ptr<ProfileSummary> Summary;
   void computeThresholds();
   // Count thresholds to answer isHotCount and isColdCount queries.
@@ -58,7 +58,8 @@
   mutable DenseMap<int, uint64_t> ThresholdCache;
 
 public:
-  ProfileSummaryInfo(Module &M) : M(M) { refresh(); }
+  ProfileSummaryInfo(const Module &M) : M(M) { refresh(); }
+
   ProfileSummaryInfo(ProfileSummaryInfo &&Arg) = default;
 
   /// If no summary is present, attempt to refresh.
diff --git a/llvm/include/llvm/IR/LLVMContext.h b/llvm/include/llvm/IR/LLVMContext.h
--- a/llvm/include/llvm/IR/LLVMContext.h
+++ b/llvm/include/llvm/IR/LLVMContext.h
@@ -237,6 +237,9 @@
   /// included in optimization diagnostics.
   void setDiagnosticsHotnessThreshold(Optional<uint64_t> Threshold);
 
+  /// Return if hotness threshold is requested from PSI.
+  bool isDiagnosticsHotnessThresholdSetFromPSI() const;
+
   /// The "main remark streamer" used by all the specialized remark streamers.
   /// This streamer keeps generic remark metadata in memory throughout the life
   /// of the LLVMContext. This metadata may be emitted in a section in object
diff --git a/llvm/include/llvm/IR/Module.h b/llvm/include/llvm/IR/Module.h
--- a/llvm/include/llvm/IR/Module.h
+++ b/llvm/include/llvm/IR/Module.h
@@ -850,7 +850,7 @@
 
   /// Returns profile summary metadata. When IsCS is true, use the context
   /// sensitive profile summary.
-  Metadata *getProfileSummary(bool IsCS);
+  Metadata *getProfileSummary(bool IsCS) const;
   /// @}
 
   /// Returns whether semantic interposition is to be respected.
diff --git a/llvm/lib/Analysis/OptimizationRemarkEmitter.cpp b/llvm/lib/Analysis/OptimizationRemarkEmitter.cpp
--- a/llvm/lib/Analysis/OptimizationRemarkEmitter.cpp
+++ b/llvm/lib/Analysis/OptimizationRemarkEmitter.cpp
@@ -15,6 +15,7 @@
 #include "llvm/Analysis/BranchProbabilityInfo.h"
 #include "llvm/Analysis/LazyBlockFrequencyInfo.h"
 #include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/LLVMContext.h"
@@ -96,9 +97,17 @@
 bool OptimizationRemarkEmitterWrapperPass::runOnFunction(Function &Fn) {
   BlockFrequencyInfo *BFI;
 
-  if (Fn.getContext().getDiagnosticsHotnessRequested())
+  auto &Context = Fn.getContext();
+  if (Context.getDiagnosticsHotnessRequested()) {
     BFI = &getAnalysis<LazyBlockFrequencyInfoPass>().getBFI();
-  else
+    // Get hotness threshold from PSI. This should only happen once.
+    if (Context.isDiagnosticsHotnessThresholdSetFromPSI()) {
+      if (ProfileSummaryInfo *PSI =
+              &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI())
+        Context.setDiagnosticsHotnessThreshold(
+            PSI->getOrCompHotCountThreshold());
+    }
+  } else
     BFI = nullptr;
 
   ORE = std::make_unique<OptimizationRemarkEmitter>(&Fn, BFI);
@@ -108,6 +117,7 @@
 void OptimizationRemarkEmitterWrapperPass::getAnalysisUsage(
     AnalysisUsage &AU) const {
   LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU);
+  AU.addRequired<ProfileSummaryInfoWrapperPass>();
   AU.setPreservesAll();
 }
 
@@ -117,10 +127,19 @@
 OptimizationRemarkEmitterAnalysis::run(Function &F,
                                        FunctionAnalysisManager &AM) {
   BlockFrequencyInfo *BFI;
+  auto &Context = F.getContext();
 
-  if (F.getContext().getDiagnosticsHotnessRequested())
+  if (Context.getDiagnosticsHotnessRequested()) {
     BFI = &AM.getResult<BlockFrequencyAnalysis>(F);
-  else
+    // Get hotness threshold from PSI. This should only happen once.
+    if (Context.isDiagnosticsHotnessThresholdSetFromPSI()) {
+      auto &MAMProxy = AM.getResult<ModuleAnalysisManagerFunctionProxy>(F);
+      if (ProfileSummaryInfo *PSI =
+              MAMProxy.getCachedResult<ProfileSummaryAnalysis>(*F.getParent()))
+        Context.setDiagnosticsHotnessThreshold(
+            PSI->getOrCompHotCountThreshold());
+    }
+  } else
     BFI = nullptr;
 
   return OptimizationRemarkEmitter(&F, BFI);
@@ -133,5 +152,6 @@
 INITIALIZE_PASS_BEGIN(OptimizationRemarkEmitterWrapperPass, ORE_NAME, ore_name,
                       false, true)
 INITIALIZE_PASS_DEPENDENCY(LazyBFIPass)
+INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)
 INITIALIZE_PASS_END(OptimizationRemarkEmitterWrapperPass, ORE_NAME, ore_name,
                     false, true)
diff --git a/llvm/lib/IR/LLVMContext.cpp b/llvm/lib/IR/LLVMContext.cpp
--- a/llvm/lib/IR/LLVMContext.cpp
+++ b/llvm/lib/IR/LLVMContext.cpp
@@ -149,10 +149,15 @@
 void LLVMContext::setDiagnosticsHotnessThreshold(Optional<uint64_t> Threshold) {
   pImpl->DiagnosticsHotnessThreshold = Threshold;
 }
+
 uint64_t LLVMContext::getDiagnosticsHotnessThreshold() const {
   return pImpl->DiagnosticsHotnessThreshold.getValueOr(UINT64_MAX);
 }
 
+bool LLVMContext::isDiagnosticsHotnessThresholdSetFromPSI() const {
+  return !pImpl->DiagnosticsHotnessThreshold.hasValue();
+}
+
 remarks::RemarkStreamer *LLVMContext::getMainRemarkStreamer() {
   return pImpl->MainRemarkStreamer.get();
 }
diff --git a/llvm/lib/IR/LLVMRemarkStreamer.cpp b/llvm/lib/IR/LLVMRemarkStreamer.cpp
--- a/llvm/lib/IR/LLVMRemarkStreamer.cpp
+++ b/llvm/lib/IR/LLVMRemarkStreamer.cpp
@@ -96,8 +96,7 @@
   if (RemarksWithHotness)
     Context.setDiagnosticsHotnessRequested(true);
 
-  if (RemarksHotnessThreshold)
-    Context.setDiagnosticsHotnessThreshold(RemarksHotnessThreshold);
+  Context.setDiagnosticsHotnessThreshold(RemarksHotnessThreshold);
 
   if (RemarksFilename.empty())
     return nullptr;
@@ -144,8 +143,7 @@
   if (RemarksWithHotness)
     Context.setDiagnosticsHotnessRequested(true);
 
-  if (RemarksHotnessThreshold)
-    Context.setDiagnosticsHotnessThreshold(RemarksHotnessThreshold);
+  Context.setDiagnosticsHotnessThreshold(RemarksHotnessThreshold);
 
   Expected<remarks::Format> Format = remarks::parseFormat(RemarksFormat);
   if (Error E = Format.takeError())
diff --git a/llvm/lib/IR/Module.cpp b/llvm/lib/IR/Module.cpp
--- a/llvm/lib/IR/Module.cpp
+++ b/llvm/lib/IR/Module.cpp
@@ -582,7 +582,7 @@
     setModuleFlag(ModFlagBehavior::Error, "ProfileSummary", M);
 }
 
-Metadata *Module::getProfileSummary(bool IsCS) {
+Metadata *Module::getProfileSummary(bool IsCS) const {
   return (IsCS ? getModuleFlag("CSProfileSummary")
                : getModuleFlag("ProfileSummary"));
 }
diff --git a/llvm/test/Other/optimization-remarks-auto.ll b/llvm/test/Other/optimization-remarks-auto.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Other/optimization-remarks-auto.ll
@@ -0,0 +1,85 @@
+;; This test verifies 'auto' hotness threshold when profile summary is available.
+;;
+;; new PM
+; RUN: rm -f %t.yaml %t.hot.yaml
+; RUN: opt < %s --disable-output --enable-new-pm \
+; RUN: --passes='inline' \
+; RUN: --pass-remarks-output=%t.yaml --pass-remarks-filter='inline' \
+; RUN: --pass-remarks-with-hotness
+; RUN: FileCheck %s -check-prefix=YAML-PASS < %t.yaml
+; RUN: FileCheck %s -check-prefix=YAML-MISS < %t.yaml
+
+;; test 'auto' threshold
+; RUN: opt < %s --disable-output --enable-new-pm \
+; RUN: --passes='module(print-profile-summary,cgscc(inline))' \
+; RUN: --pass-remarks-output=%t.hot.yaml --pass-remarks-filter='inline' \
+; RUN: --pass-remarks-with-hotness --pass-remarks-hotness-threshold=auto 2>&1 | FileCheck %s
+; RUN: FileCheck %s -check-prefix=YAML-PASS < %t.hot.yaml
+; RUN: not FileCheck %s -check-prefix=YAML-MISS < %t.hot.yaml
+
+; RUN: opt < %s --disable-output --enable-new-pm \
+; RUN: --passes='module(print-profile-summary,cgscc(inline))' \
+; RUN: --pass-remarks=inline --pass-remarks-missed=inline --pass-remarks-analysis=inline \
+; RUN: --pass-remarks-with-hotness --pass-remarks-hotness-threshold=auto 2>&1 | FileCheck %s -check-prefix=CHECK-RPASS
+
+; YAML-PASS:      --- !Passed
+; YAML-PASS-NEXT: Pass:            inline
+; YAML-PASS-NEXT: Name:            Inlined
+; YAML-PASS-NEXT: Function:        caller1
+; YAML-PASS-NEXT: Hotness:         400
+
+; YAML-MISS:      --- !Missed
+; YAML-MISS-NEXT: Pass:            inline
+; YAML-MISS-NEXT: Name:            NeverInline
+; YAML-MISS-NEXT: Function:        caller2
+; YAML-MISS-NEXT: Hotness:         1
+
+; CHECK-RPASS: callee1 inlined into caller1 with (cost=-30, threshold=4500) (hotness: 400)
+; CHECK-RPASS-NOT: callee2 not inlined into caller2 because it should never be inlined (cost=never): noinline function attribute (hotness: 1)
+
+define void @callee1() !prof !20 {
+; CHECK: callee1 :hot
+entry:
+  ret void
+}
+
+; Function Attrs: noinline
+define void @callee2() noinline !prof !21 {
+; CHECK: callee2 :cold
+entry:
+  ret void
+}
+
+define void @caller1() !prof !20 {
+; CHECK: caller1 :hot
+entry:
+  call void @callee1()
+  ret void
+}
+
+define void @caller2() !prof !21 {
+; CHECK: caller2 :cold
+entry:
+  call void @callee2()
+  ret void
+}
+
+!llvm.module.flags = !{!1}
+!20 = !{!"function_entry_count", i64 400}
+!21 = !{!"function_entry_count", i64 1}
+
+!1 = !{i32 1, !"ProfileSummary", !2}
+!2 = !{!3, !4, !5, !6, !7, !8, !9, !10}
+!3 = !{!"ProfileFormat", !"InstrProf"}
+!4 = !{!"TotalCount", i64 10000}
+!5 = !{!"MaxCount", i64 10}
+!6 = !{!"MaxInternalCount", i64 1}
+!7 = !{!"MaxFunctionCount", i64 1000}
+!8 = !{!"NumCounts", i64 3}
+!9 = !{!"NumFunctions", i64 3}
+!10 = !{!"DetailedSummary", !11}
+!11 = !{!12, !13, !14}
+!12 = !{i32 10000, i64 100, i32 1}
+!13 = !{i32 999000, i64 100, i32 1}
+!14 = !{i32 999999, i64 1, i32 2}
+
diff --git a/llvm/test/Transforms/SampleProfile/Inputs/remarks-hotness.prof b/llvm/test/Transforms/SampleProfile/Inputs/remarks-hotness.prof
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/SampleProfile/Inputs/remarks-hotness.prof
@@ -0,0 +1,8 @@
+_Z7callee1v:600:600
+ 1: 600
+_Z7callee2v:1:1
+ 1: 1
+_Z7caller1v:400:400
+ 1: 400
+_Z7caller2v:1:1
+ 1: 1
diff --git a/llvm/test/Transforms/SampleProfile/remarks-hotness.ll b/llvm/test/Transforms/SampleProfile/remarks-hotness.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/SampleProfile/remarks-hotness.ll
@@ -0,0 +1,96 @@
+;; This test verifies 'auto' hotness threshold when profile file is provided.
+;;
+;; new PM
+; RUN: rm -f %t.yaml %t.hot.yaml
+; RUN: opt %s --enable-new-pm --passes='sample-profile,cgscc(inline)' \
+; RUN: --sample-profile-file=%S/Inputs/remarks-hotness.prof \
+; RUN: -S --pass-remarks-filter=inline --pass-remarks-output=%t.yaml \
+; RUN: -pass-remarks-with-hotness --disable-output
+; RUN: FileCheck %s -check-prefix=YAML-PASS < %t.yaml
+; RUN: FileCheck %s -check-prefix=YAML-MISS < %t.yaml
+
+;; test 'auto' threshold
+; RUN: opt %s --enable-new-pm --passes='sample-profile,cgscc(inline)' \
+; RUN: --sample-profile-file=%S/Inputs/remarks-hotness.prof \
+; RUN: -S --pass-remarks-filter=inline --pass-remarks-output=%t.hot.yaml \
+; RUN: --pass-remarks-with-hotness --pass-remarks-hotness-threshold=auto --disable-output
+; RUN: FileCheck %s -check-prefix=YAML-PASS < %t.hot.yaml
+; RUN: not FileCheck %s -check-prefix=YAML-MISS < %t.hot.yaml
+
+; RUN: opt %s --enable-new-pm --passes='sample-profile,cgscc(inline)' \
+; RUN: --sample-profile-file=%S/Inputs/remarks-hotness.prof \
+; RUN: -S --pass-remarks=inline --pass-remarks-missed=inline --pass-remarks-analysis=inline \
+; RUN: --pass-remarks-with-hotness --pass-remarks-hotness-threshold=auto --disable-output 2>&1 | FileCheck %s -check-prefix=CHECK-RPASS
+
+; YAML-PASS:      --- !Passed
+; YAML-PASS-NEXT: Pass:            inline
+; YAML-PASS-NEXT: Name:            Inlined
+; YAML-PASS-NEXT: DebugLoc:        { File: remarks-hotness.cpp, Line: 10, Column: 10 }
+; YAML-PASS-NEXT: Function:        _Z7caller1v
+; YAML-PASS-NEXT: Hotness:         401
+
+; YAML-MISS:      --- !Missed
+; YAML-MISS-NEXT: Pass:            inline
+; YAML-MISS-NEXT: Name:            NeverInline
+; YAML-MISS-NEXT: DebugLoc:        { File: remarks-hotness.cpp, Line: 14, Column: 10 }
+; YAML-MISS-NEXT: Function:        _Z7caller2v
+; YAML-MISS-NEXT: Hotness:         2
+
+; CHECK-RPASS: _Z7callee1v inlined into _Z7caller1v with (cost=-30, threshold=4500) at callsite _Z7caller1v:1 (hotness: 401)
+; CHECK-RPASS-NOT: _Z7callee2v not inlined into _Z7caller2v because it should never be inlined (cost=never): noinline function attribute (hotness: 2)
+
+; ModuleID = 'remarks-hotness.cpp'
+source_filename = "remarks-hotness.cpp"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: use-sample-profile
+define dso_local i32 @_Z7callee1v() #0 !dbg !7 {
+  ret i32 1, !dbg !11
+}
+
+; Function Attrs: noinline nounwind uwtable use-sample-profile
+define dso_local i32 @_Z7callee2v() #1 !dbg !12 {
+  ret i32 2, !dbg !13
+}
+
+; Function Attrs: use-sample-profile
+define dso_local i32 @_Z7caller1v() #0 !dbg !14 {
+  %1 = call i32 @_Z7callee1v(), !dbg !15
+  ret i32 %1, !dbg !16
+}
+
+; Function Attrs: use-sample-profile
+define dso_local i32 @_Z7caller2v() #0 !dbg !17 {
+  %1 = call i32 @_Z7callee2v(), !dbg !18
+  ret i32 %1, !dbg !19
+}
+
+attributes #0 = { "use-sample-profile" }
+attributes #1 = { noinline nounwind uwtable "use-sample-profile" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5}
+!llvm.ident = !{!6}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, debugInfoForProfiling: true, nameTableKind: None)
+!1 = !DIFile(filename: "remarks-hotness.cpp", directory: ".")
+!2 = !{}
+!3 = !{i32 7, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{!"clang version 11.0.0"}
+!7 = distinct !DISubprogram(name: "callee1", linkageName: "_Z7callee1v", scope: !1, file: !1, line: 1, type: !8, scopeLine: 1, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!8 = !DISubroutineType(types: !9)
+!9 = !{!10}
+!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!11 = !DILocation(line: 2, column: 3, scope: !7)
+!12 = distinct !DISubprogram(name: "callee2", linkageName: "_Z7callee2v", scope: !1, file: !1, line: 5, type: !8, scopeLine: 5, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!13 = !DILocation(line: 6, column: 3, scope: !12)
+!14 = distinct !DISubprogram(name: "caller1", linkageName: "_Z7caller1v", scope: !1, file: !1, line: 9, type: !8, scopeLine: 9, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!15 = !DILocation(line: 10, column: 10, scope: !14)
+!16 = !DILocation(line: 10, column: 3, scope: !14)
+!17 = distinct !DISubprogram(name: "caller2", linkageName: "_Z7caller2v", scope: !1, file: !1, line: 13, type: !8, scopeLine: 13, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!18 = !DILocation(line: 14, column: 10, scope: !17)
+!19 = !DILocation(line: 14, column: 3, scope: !17)
+