Support for 64-bit architectures: x86 in 64-bit mode

This commit enriches the IA32 port so that it supports x86 processors in 64-bit mode as well as in 32-bit mode, depending on the value of Archi.ptr64, which itself is set from the configuration model.

To activate x86-64 bit support, configure with "x86_64-linux".

Main steps:
- Enrich Op.v and Asm.v with 64-bit operations
- SelectLong: in 64-bit mode, use 64-bit operations directly; in 32-bit mode, fall back on the old implementation based on pairs of 32-bit integers
- Conventions1: support x86-64 ABI in addition to the 32-bit ABI.
- Add support for the new 64-bit operations everywhere.
- runtime/x86_64: implementation of the supporting library appropriate for x86 in 64-bit mode

To do:
- More optimizations are possible on 64-bit integer arithmetic operations.
- Could add new chunks to load, say, an unsigned byte into a 64-bit long
  (currently we load as a 32-bit int then zero-extend).
- Implements the wrong ABI for struct passing.

1 files changed, 13 insertions, 2 deletions

diff --git a/ia32/extractionMachdep.v b/ia32/extractionMachdep.v
index 3c6ee2e0..8b395579 100644
--- a/ia32/extractionMachdep.v
+++ b/ia32/extractionMachdep.v
@@ -10,11 +10,22 @@
 (*                                                                     *)
 (* *********************************************************************)
 
-(* Additional extraction directives specific to the IA32 port *)
+(* Additional extraction directives specific to the x86-64 port *)
 
-Require SelectOp.
+Require Archi SelectOp ConstpropOp.
+
+(* Archi *)
+
+Extract Constant Archi.ptr64 =>
+  "Configuration.model = ""64"" ".
 
 (* SelectOp *)
 
 Extract Constant SelectOp.symbol_is_external =>
   "fun id -> Configuration.system = ""macosx"" && C2C.atom_is_extern id".
+
+(* ConstpropOp *)
+
+Extract Constant ConstpropOp.symbol_is_external =>
+  "fun id -> Configuration.system = ""macosx"" && C2C.atom_is_extern id".
+