Subzero: Add a random number generator.

src/IceGlobalContext.cpp

Index: src/IceGlobalContext.cpp
diff --git a/src/IceGlobalContext.cpp b/src/IceGlobalContext.cpp
index 5dd8b6306ec89c6a8eaa1c62c5785b7363020556..56d025c6c2726ad82c7346b5d6d94347bd978898 100644
--- a/src/IceGlobalContext.cpp
+++ b/src/IceGlobalContext.cpp
@@ -15,6 +15,8 @@
 #include <ctype.h> // isdigit(), isupper()
 #include <locale>  // locale
 
+#include "llvm/Support/CommandLine.h"
+
 #include "IceDefs.h"
 #include "IceTypes.h"
 #include "IceCfg.h"
@@ -24,6 +26,14 @@
 
 namespace Ice {
 
+namespace {
+namespace cl = llvm::cl;
+
+cl::opt<uint64_t> RandomSeed("random-seed",
+                             cl::desc("Seed the random number generator"),
+                             cl::init(1));

[Jim Stichnoth, 2014/08/08 05:05:38]

Can you default initialize to time(0) or something like that?

[wala, 2014/08/08 16:36:13]

Done.

+} // end anonymous namespace
+
 // TypePool maps constants of type KeyType (e.g. float) to pointers to
 // type ValueType (e.g. ConstantFloat).  KeyType values are compared
 // using memcmp() because of potential NaN values in KeyType values.
@@ -119,7 +129,8 @@ GlobalContext::GlobalContext(llvm::raw_ostream *OsDump,
                              IceString TestPrefix)
     : StrDump(OsDump), StrEmit(OsEmit), VMask(Mask),
       ConstPool(new ConstantPool()), Arch(Arch), Opt(Opt),
-      TestPrefix(TestPrefix), HasEmittedFirstMethod(false) {}
+      TestPrefix(TestPrefix), HasEmittedFirstMethod(false),
+      RNG(RandomSeed) {}
 
 // Scan a string for S[0-9A-Z]*_ patterns and replace them with
 // S<num>_ where <num> is the next base-36 value.  If a type name