From fb418bf2e6270d215ba465105beb70caf6943bf4 Mon Sep 17 00:00:00 2001
From: Moritz Warning <moritzwarning@web.de>
Date: Wed, 23 Feb 2011 23:50:53 +0100
Subject: [PATCH] Added -disable-red-zone flag.

This will disable the usage of the 'red-zone' in ABIs that make use of it (like x86). This mimics the exact flag used by clang. It is comparable to the -mno-red-zone flag in gcc. - thanks to wilkie
---
 gen/cl_options.cpp | 4 ++++
 gen/cl_options.h   | 1 +
 gen/functions.cpp  | 4 ++++
 3 files changed, 9 insertions(+)

diff --git a/gen/cl_options.cpp b/gen/cl_options.cpp
index cbb8c5c1..7d500aa3 100644
--- a/gen/cl_options.cpp
+++ b/gen/cl_options.cpp
@@ -100,6 +100,10 @@ cl::opt<bool> output_s("output-s",
 cl::opt<cl::boolOrDefault> output_o("output-o",
     cl::desc("Write native object"));
 
+// Disabling Red Zone
+cl::opt<bool> disableRedZone("disable-red-zone",
+  cl::desc("Do not emit code that uses the red zone."),
+  cl::init(false));
 
 // DDoc options
 static cl::opt<bool, true> doDdoc("D",
diff --git a/gen/cl_options.h b/gen/cl_options.h
index f7bf623a..8965a20e 100644
--- a/gen/cl_options.h
+++ b/gen/cl_options.h
@@ -26,6 +26,7 @@ namespace opts {
     extern cl::opt<bool> output_ll;
     extern cl::opt<bool> output_s;
     extern cl::opt<cl::boolOrDefault> output_o;
+    extern cl::opt<bool> disableRedZone;
     extern cl::opt<std::string> ddocDir;
     extern cl::opt<std::string> ddocFile;
     extern cl::opt<std::string> jsonFile;
diff --git a/gen/functions.cpp b/gen/functions.cpp
index 8065dc0e..32c25bd8 100644
--- a/gen/functions.cpp
+++ b/gen/functions.cpp
@@ -22,6 +22,7 @@
 #include "gen/dvalue.h"
 #include "gen/abi.h"
 #include "gen/nested.h"
+#include "gen/cl_options.h"
 
 using namespace llvm::Attribute;
 
@@ -501,6 +502,9 @@ void DtoDeclareFunction(FuncDeclaration* fdecl)
     // parameter attributes
     if (!fdecl->isIntrinsic()) {
         set_param_attrs(f, func, fdecl);
+        if (opts::disableRedZone) {
+            func->addFnAttr(NoRedZone);
+        }
     }
 
     // main