Introduce model of global initializers in Subzero.

src/IceGlobalInits.cpp

Index: src/IceGlobalInits.cpp
diff --git a/src/IceGlobalInits.cpp b/src/IceGlobalInits.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..4d9dadb4c076de53fdf2f8d1b57ddd2701ed102e
--- /dev/null
+++ b/src/IceGlobalInits.cpp
@@ -0,0 +1,139 @@
+//===- subzero/src/IceGlobalInits.cpp - Global initializers ---------------===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the notion of global addresses and
+// initializers in Subzero.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Value.h"
+
+#include "IceDefs.h"
+#include "IceGlobalInits.h"
+#include "IceTypes.h"
+
+namespace {
+char hexdigit(unsigned X) { return X < 10 ? '0' + X : 'A' + X - 10; }
+}
+
+namespace Ice {
+
+GlobalAddress::~GlobalAddress() { llvm::DeleteContainerPointers(Initializers); }
+
+void GlobalAddress::dumpType(Ostream &Stream) const {
+  if (Initializers.size() == 1) {
+    Initializers.front()->dumpType(Stream);
+  } else {
+    Stream << "<{ ";
+    bool IsFirst = true;
+    for (Initializer *Init : Initializers) {
+      if (IsFirst) {
+        IsFirst = false;
+      } else {
+        Stream << ", ";
+      }
+      Init->dumpType(Stream);
+    }
+    Stream << " }>";
+  }
+}
+
+void GlobalAddress::dump(Ostream &Stream) const {
+  Stream << "@" << getName() << " = internal "
+         << (IsConstant ? "constant" : "global") << " ";
+
+  // Add initializer.
+  if (Initializers.size() == 1) {
+    Initializers.front()->dump(Stream);
+  } else {
+    dumpType(Stream);
+    Stream << " <{ ";
+    bool IsFirst = true;
+    for (Initializer *Init : Initializers) {
+      if (IsFirst) {
+        IsFirst = false;
+      } else {
+        Stream << ", ";
+      }
+      Init->dump(Stream);
+    }
+    Stream << " }>";
+  }
+
+  // Add alignment.
+  if (Alignment > 0)
+    Stream << ", align " << Alignment;
+  Stream << "\n";
+}
+
+void GlobalAddress::Initializer::dumpType(Ostream &Stream) const {
+  Stream << "[" << getNumBytes() << " x " << Ice::IceType_i8 << "]";
+}
+
+void GlobalAddress::DataInitializer::dump(Ostream &Stream) const {
+  dumpType(Stream);
+  Stream << " c\"";
+  // Code taken from PrintEscapedString() in AsmWriter.cpp.  Keep
+  // the strings in the same format as the .ll file for practical
+  // diffing.
+  for (uint8_t C : Contents) {
+    if (isprint(C) && C != '\\' && C != '"')
+      Stream << C;
+    else
+      Stream << '\\' << hexdigit(C >> 4) << hexdigit(C & 0x0F);
+  }
+  Stream << "\"";
+}
+
+void GlobalAddress::ZeroInitializer::dump(Ostream &Stream) const {
+  dumpType(Stream);
+  Stream << " zeroinitializer";
+}
+
+IceString GlobalAddress::RelocInitializer::getName() const {
+  switch (Address.getKind()) {
+  case FunctionRelocation:
+    return Address.getFunction()->getName();
+  case GlobalAddressRelocation:
+    return Address.getGlobalAddr()->getName();
+  default:
+    llvm::report_fatal_error("Malformed relocation address!");
+  }
+}
+
+void GlobalAddress::RelocInitializer::dumpType(Ostream &Stream) const {
+  Stream << Ice::IceType_i32;
+}
+
+void GlobalAddress::RelocInitializer::dump(Ostream &Stream) const {
+  if (Offset != 0) {
+    dumpType(Stream);
+    Stream << " add (";
+  }
+  dumpType(Stream);
+  Stream << " ptrtoint (";
+  if (Address.getKind() == FunctionRelocation) {
+    Stream << *Address.getFunction()->getType() << " @"
+           << Address.getFunction()->getName();
+  } else {
+    Address.getGlobalAddr()->dumpType(Stream);
+    Stream << "* @" << Address.getGlobalAddr()->getName();
+  }
+  Stream << " to ";
+  dumpType(Stream);
+  Stream << ")";
+  if (Offset != 0) {
+    Stream << ", ";
+    dumpType(Stream);
+    Stream << " " << Offset << ")";
+  }
+}
+}