4 files changed, 21 insertions, 5 deletions
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index c2b4c95ae9e..8857ffdde49 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -1784,6 +1784,9 @@ void CodeGenModule::ConstructDefaultFnAttrList(StringRef Name, bool HasOptnone,
       FuncAttrs.addAttribute("stackrealign");
     if (CodeGenOpts.Backchain)
       FuncAttrs.addAttribute("backchain");
+
+    if (CodeGenOpts.SpeculativeLoadHardening)
+      FuncAttrs.addAttribute(llvm::Attribute::SpeculativeLoadHardening);
   }
 
   if (getLangOpts().assumeFunctionsAreConvergent()) {
diff --git a/clang/lib/Driver/ToolChains/Arch/X86.cpp b/clang/lib/Driver/ToolChains/Arch/X86.cpp
index ff2023c2cbe..bc707857d8f 100644
--- a/clang/lib/Driver/ToolChains/Arch/X86.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/X86.cpp
@@ -146,15 +146,23 @@ void x86::getX86TargetFeatures(const Driver &D, const llvm::Triple &Triple,
 
   // Translate the high level `-mretpoline` flag to the specific target feature
   // flags. We also detect if the user asked for retpoline external thunks but
-  // failed to ask for retpolines themselves. This is a bit hacky but keeps
-  // existing usages working. We should consider deprecated this and instead
-  // warning if the user requests external retpoline thunks and *doesn't*
-  // request some form of retpolines.
-  if (Args.hasArgNoClaim(options::OPT_mretpoline, options::OPT_mno_retpoline)) {
+  // failed to ask for retpolines themselves (through any of the different
+  // flags). This is a bit hacky but keeps existing usages working. We should
+  // consider deprecating this and instead warn if the user requests external
+  // retpoline thunks and *doesn't* request some form of retpolines.
+  if (Args.hasArgNoClaim(options::OPT_mretpoline, options::OPT_mno_retpoline,
+                         options::OPT_mspeculative_load_hardening,
+                         options::OPT_mno_speculative_load_hardening)) {
     if (Args.hasFlag(options::OPT_mretpoline, options::OPT_mno_retpoline,
                      false)) {
       Features.push_back("+retpoline-indirect-calls");
       Features.push_back("+retpoline-indirect-branches");
+    } else if (Args.hasFlag(options::OPT_mspeculative_load_hardening,
+                            options::OPT_mno_speculative_load_hardening,
+                            false)) {
+      // On x86, speculative load hardening relies on at least using retpolines
+      // for indirect calls.
+      Features.push_back("+retpoline-indirect-calls");
     }
   } else if (Args.hasFlag(options::OPT_mretpoline_external_thunk,
                           options::OPT_mno_retpoline_external_thunk, false)) {
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index ff083c79f10..79129a7a7c6 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -4132,6 +4132,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   Args.AddLastArg(CmdArgs, options::OPT_pthread);
 
+  Args.AddLastArg(CmdArgs, options::OPT_mspeculative_load_hardening,
+                  options::OPT_mno_speculative_load_hardening);
+
   RenderSSPOptions(getToolChain(), Args, CmdArgs, KernelOrKext);
 
   // Translate -mstackrealign
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 4ac79293282..5210314493d 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1147,6 +1147,8 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
 
   Opts.KeepStaticConsts = Args.hasArg(OPT_fkeep_static_consts);
 
+  Opts.SpeculativeLoadHardening = Args.hasArg(OPT_mspeculative_load_hardening);
+
   return Success;
 }