Implement command line options for stack probe space

This code adds the -mstack-probe-size command line option and implements the /Gs
compiler switch for clang-cl.

This should fix http://llvm.org/bugs/show_bug.cgi?id=21896

Patch by Andrew H!

Differential Revision: http://reviews.llvm.org/D6685

llvm-svn: 226601

3 files changed, 49 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 6ad34951576..93dd6dbb0f8 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -1616,6 +1616,9 @@ public:
         bool d, bool p, bool w, unsigned RegParms)
     : X86_32TargetCodeGenInfo(CGT, d, p, w, RegParms) {}
 
+  void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
+                           CodeGen::CodeGenModule &CGM) const override;
+
   void getDependentLibraryOption(llvm::StringRef Lib,
                                  llvm::SmallString<24> &Opt) const override {
     Opt = "/DEFAULTLIB:";
@@ -1629,12 +1632,35 @@ public:
   }
 };
 
+static void addStackProbeSizeTargetAttribute(const Decl *D,
+                                             llvm::GlobalValue *GV,
+                                             CodeGen::CodeGenModule &CGM) {
+  if (isa<FunctionDecl>(D)) {
+    if (CGM.getCodeGenOpts().StackProbeSize != 4096) {
+      llvm::Function *Fn = cast<llvm::Function>(GV);
+
+      Fn->addFnAttr("stack-probe-size", llvm::utostr(CGM.getCodeGenOpts().StackProbeSize));
+    }
+  }
+}
+
+void WinX86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
+                                                     llvm::GlobalValue *GV,
+                                            CodeGen::CodeGenModule &CGM) const {
+  X86_32TargetCodeGenInfo::SetTargetAttributes(D, GV, CGM);
+
+  addStackProbeSizeTargetAttribute(D, GV, CGM);
+}
+
 class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
   bool HasAVX;
 public:
   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
     : TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)), HasAVX(HasAVX) {}
 
+  void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
+                           CodeGen::CodeGenModule &CGM) const override;
+
   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
     return 7;
   }
@@ -1666,6 +1692,13 @@ public:
   }
 };
 
+void WinX86_64TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
+                                                     llvm::GlobalValue *GV,
+                                            CodeGen::CodeGenModule &CGM) const {
+  TargetCodeGenInfo::SetTargetAttributes(D, GV, CGM);
+
+  addStackProbeSizeTargetAttribute(D, GV, CGM);
+}
 }
 
 void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index db43fde7634..680539bcfe2 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -3733,6 +3733,15 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back(Args.MakeArgString("-mstack-alignment=" + alignment));
   }
 
+  if (Args.hasArg(options::OPT_mstack_probe_size)) {
+    StringRef Size = Args.getLastArgValue(options::OPT_mstack_probe_size);
+
+    if (!Size.empty())
+      CmdArgs.push_back(Args.MakeArgString("-mstack-probe-size=" + Size));
+    else
+      CmdArgs.push_back("-mstack-probe-size=0");
+  }
+
   if (getToolChain().getTriple().getArch() == llvm::Triple::aarch64 ||
       getToolChain().getTriple().getArch() == llvm::Triple::aarch64_be)
     CmdArgs.push_back("-fallow-half-arguments-and-returns");
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 921a0d2d80e..dd1a60611aa 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -523,6 +523,13 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
     Opts.StackAlignment = StackAlignment;
   }
 
+  if (Arg *A = Args.getLastArg(OPT_mstack_probe_size)) {
+    StringRef Val = A->getValue();
+    unsigned StackProbeSize = Opts.StackProbeSize;
+    Val.getAsInteger(0, StackProbeSize);
+    Opts.StackProbeSize = StackProbeSize;
+  }
+
   if (Arg *A = Args.getLastArg(OPT_fobjc_dispatch_method_EQ)) {
     StringRef Name = A->getValue();
     unsigned Method = llvm::StringSwitch<unsigned>(Name)