Subzero: Add Non-SFI support for x86-32.

src/IceAssemblerX86BaseImpl.h

 //===- subzero/src/IceAssemblerX86BaseImpl.h - base x86 assembler -*- C++ -*-=//
 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Modified by the Subzero authors.
 //
 //===----------------------------------------------------------------------===//
 //
 //                        The Subzero Code Generator
@@ skipping 104 matching lines @@
   emitRex(RexTypeIrrelevant, address, RexRegIrrelevant);
   emitUint8(0xFF);
   emitOperand(2, address);
 }
 
 template <class Machine>
 void AssemblerX86Base<Machine>::call(const ConstantRelocatable *label) {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   intptr_t call_start = Buffer.getPosition();
   emitUint8(0xE8);
-  emitFixup(this->createFixup(Traits::PcRelFixup, label));
+  emitFixup(this->createFixup(Traits::FixupKindPcRel, label));

[John, 2015/12/22 15:44:38]

I prefer the other name. The prefix "FixupKind" just bloats the code more than
it is needed. 'PcRelFixup' conveys the idea (to me, at least) that the member is
a Pc Relative Fixup. If you care enough to distinguish between the enum and an
instance of the Fixup class, then I would strongly suggest using
'PcRelFixupKind' (but I still think 'kind' is unnecessary here)

[Jim Stichnoth, 2015/12/28 07:54:07]

Good point.

For this naming, I'm trying to distinguish between constexpr values in the
Traits namespace, and values of static members in the TargetLowering object that
depend on flags (like --nonsfi or --sandbox).

How about this approach.  For the constexpr names, I changed:
  FixupKindPcRel  --> FK_PcRel
  FixupKindGotPC  --> FK_GotPC
  FixupKindAbs    --> FK_Abs
  FixupKindGofoff --> FK_Gotoff
in the style of enum value naming.

   emitInt32(-4);
   assert((Buffer.getPosition() - call_start) == kCallExternalLabelSize);
   (void)call_start;
 }
 
 template <class Machine>
 void AssemblerX86Base<Machine>::call(const Immediate &abs_address) {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   intptr_t call_start = Buffer.getPosition();
   emitUint8(0xE8);
-  emitFixup(this->createFixup(Traits::PcRelFixup, AssemblerFixup::NullSymbol));
+  emitFixup(
+      this->createFixup(Traits::FixupKindPcRel, AssemblerFixup::NullSymbol));
   emitInt32(abs_address.value() - 4);
   assert((Buffer.getPosition() - call_start) == kCallExternalLabelSize);
   (void)call_start;
 }
 
 template <class Machine>
 void AssemblerX86Base<Machine>::pushl(typename Traits::GPRRegister reg) {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   emitRexB(RexTypeIrrelevant, reg);
   emitUint8(0x50 + gprEncoding(reg));
@@ skipping 2978 matching lines @@
     emitLabelLink(label);
   }
 }
 
 template <class Machine>
 void AssemblerX86Base<Machine>::j(typename Traits::Cond::BrCond condition,
                                   const ConstantRelocatable *label) {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   emitUint8(0x0F);
   emitUint8(0x80 + condition);
-  emitFixup(this->createFixup(Traits::PcRelFixup, label));
+  assert(0 && "Untested - please verify and then remove this assert.");
+  emitFixup(this->createFixup(Traits::FixupKindPcRel, label));
   emitInt32(-4);
 }
 
 template <class Machine>
 void AssemblerX86Base<Machine>::jmp(typename Traits::GPRRegister reg) {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   emitRexB(RexTypeIrrelevant, reg);
   emitUint8(0xFF);
   emitRegisterOperand(4, gprEncoding(reg));
 }
@@ skipping 19 matching lines @@
   } else {
     emitUint8(0xE9);
     emitLabelLink(label);
   }
 }
 
 template <class Machine>
 void AssemblerX86Base<Machine>::jmp(const ConstantRelocatable *label) {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   emitUint8(0xE9);
-  emitFixup(this->createFixup(Traits::PcRelFixup, label));
+  assert(0 && "Untested - please verify and then remove this assert.");
+  emitFixup(this->createFixup(Traits::FixupKindPcRel, label));
   emitInt32(-4);
 }
 
 template <class Machine> void AssemblerX86Base<Machine>::mfence() {
   AssemblerBuffer::EnsureCapacity ensured(&Buffer);
   emitUint8(0x0F);
   emitUint8(0xAE);
   emitUint8(0xF0);
 }
 
@@ skipping 307 matching lines @@
   (void)shifter;
   if (Ty == IceType_i16)
     emitOperandSizeOverride();
   emitRexB(Ty, operand.rm());
   emitUint8(isByteSizedArithType(Ty) ? 0xD2 : 0xD3);
   emitOperand(rm, operand);
 }
 
 } // end of namespace X86Internal
 } // end of namespace Ice