From f26679c7195e99b32f95ea9f25b47b9981e15d3d Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Mon, 23 May 2016 00:34:05 +0200
Subject: [PATCH] LJ_GC64: Add support for 64 bit GCobj constants in the IR.

Contributed by Peter Cawley.
---
 src/lj_asm.c | 11 ++++++++++-
 src/lj_ir.c  | 29 ++++++++++++++++++++---------
 src/lj_ir.h  |  6 +++---
 3 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/src/lj_asm.c b/src/lj_asm.c
index 0b3e770a..9f784cc8 100644
--- a/src/lj_asm.c
+++ b/src/lj_asm.c
@@ -704,6 +704,11 @@ static void ra_left(ASMState *as, Reg dest, IRRef lref)
       } else if (ir->o == IR_KINT64) {
 	emit_loadk64(as, dest, ir);
 	return;
+#if LJ_GC64
+      } else if (ir->o == IR_KGC || ir->o == IR_KPTR || ir->o == IR_KKPTR) {
+	emit_loadk64(as, dest, ir);
+	return;
+#endif
 #endif
       } else if (ir->o != IR_KPRI) {
 	lua_assert(ir->o == IR_KINT || ir->o == IR_KGC ||
@@ -1933,7 +1938,7 @@ static void asm_tail_link(ASMState *as)
   emit_addptr(as, RID_BASE, 8*(int32_t)baseslot);
 
   if (as->J->ktrace) {  /* Patch ktrace slot with the final GCtrace pointer. */
-    setgcref(IR(as->J->ktrace)->gcr, obj2gco(as->J->curfinal));
+    setgcref(IR(as->J->ktrace)[LJ_GC64].gcr, obj2gco(as->J->curfinal));
     IR(as->J->ktrace)->o = IR_KGC;
   }
 
@@ -1965,8 +1970,12 @@ static void asm_setup_regsp(ASMState *as)
   for (ir = IR(T->nk), lastir = IR(REF_BASE); ir < lastir; ir++) {
     ir->prev = REGSP_INIT;
     if (irt_is64(ir->t) && ir->o != IR_KNULL) {
+#if LJ_GC64
+      ir->i = 0;  /* Will become non-zero only for RIP-relative addresses. */
+#else
       /* Make life easier for backends by putting address of constant in i. */
       ir->i = (int32_t)(intptr_t)(ir+1);
+#endif
       ir++;
     }
   }
diff --git a/src/lj_ir.c b/src/lj_ir.c
index 9c0a2224..0a206ebb 100644
--- a/src/lj_ir.c
+++ b/src/lj_ir.c
@@ -185,6 +185,12 @@ static LJ_AINLINE IRRef ir_nextk64(jit_State *J)
   return ref;
 }
 
+#if LJ_GC64
+#define ir_nextkgc ir_nextk64
+#else
+#define ir_nextkgc ir_nextk
+#endif
+
 /* Intern int32_t constant. */
 TRef LJ_FASTCALL lj_ir_kint(jit_State *J, int32_t k)
 {
@@ -268,15 +274,14 @@ TRef lj_ir_kgc(jit_State *J, GCobj *o, IRType t)
 {
   IRIns *ir, *cir = J->cur.ir;
   IRRef ref;
-  lua_assert(!LJ_GC64);  /* TODO_GC64: major changes required. */
   lua_assert(!isdead(J2G(J), o));
   for (ref = J->chain[IR_KGC]; ref; ref = cir[ref].prev)
     if (ir_kgc(&cir[ref]) == o)
       goto found;
-  ref = ir_nextk(J);
+  ref = ir_nextkgc(J);
   ir = IR(ref);
   /* NOBARRIER: Current trace is a GC root. */
-  setgcref(ir->gcr, o);
+  setgcref(ir[LJ_GC64].gcr, o);
   ir->t.irt = (uint8_t)t;
   ir->o = IR_KGC;
   ir->prev = J->chain[IR_KGC];
@@ -288,33 +293,39 @@ found:
 /* Allocate GCtrace constant placeholder (no interning). */
 TRef lj_ir_ktrace(jit_State *J)
 {
-  IRRef ref = ir_nextk(J);
+  IRRef ref = ir_nextkgc(J);
   IRIns *ir = IR(ref);
   lua_assert(irt_toitype_(IRT_P64) == LJ_TTRACE);
   ir->t.irt = IRT_P64;
-  ir->o = IR_KNULL;  /* Not IR_KGC yet, but same size. */
+  ir->o = LJ_GC64 ? IR_KNUM : IR_KNULL;  /* Not IR_KGC yet, but same size. */
   ir->prev = 0;
   return TREF(ref, IRT_P64);
 }
 
-/* Intern 32 bit pointer constant. */
+/* Intern pointer constant. */
 TRef lj_ir_kptr_(jit_State *J, IROp op, void *ptr)
 {
   IRIns *ir, *cir = J->cur.ir;
   IRRef ref;
+#if LJ_64 && !LJ_GC64
   lua_assert((void *)(uintptr_t)u32ptr(ptr) == ptr);
+#endif
   for (ref = J->chain[op]; ref; ref = cir[ref].prev)
     if (ir_kptr(&cir[ref]) == ptr)
       goto found;
+#if LJ_GC64
+  ref = ir_nextk64(J);
+#else
   ref = ir_nextk(J);
+#endif
   ir = IR(ref);
-  setmref(ir->ptr, ptr);
-  ir->t.irt = IRT_P32;
+  setmref(ir[LJ_GC64].ptr, ptr);
+  ir->t.irt = IRT_PGC;
   ir->o = op;
   ir->prev = J->chain[op];
   J->chain[op] = (IRRef1)ref;
 found:
-  return TREF(ref, IRT_P32);
+  return TREF(ref, IRT_PGC);
 }
 
 /* Intern typed NULL constant. */
diff --git a/src/lj_ir.h b/src/lj_ir.h
index 03377ec1..8b2fe638 100644
--- a/src/lj_ir.h
+++ b/src/lj_ir.h
@@ -557,8 +557,7 @@ typedef union IRIns {
   TValue tv;		/* TValue constant (overlaps entire slot). */
 } IRIns;
 
-/* TODO_GC64: major changes required. */
-#define ir_kgc(ir)	check_exp((ir)->o == IR_KGC, gcref((ir)->gcr))
+#define ir_kgc(ir)	check_exp((ir)->o == IR_KGC, gcref((ir)[LJ_GC64].gcr))
 #define ir_kstr(ir)	(gco2str(ir_kgc((ir))))
 #define ir_ktab(ir)	(gco2tab(ir_kgc((ir))))
 #define ir_kfunc(ir)	(gco2func(ir_kgc((ir))))
@@ -568,7 +567,8 @@ typedef union IRIns {
 #define ir_k64(ir) \
   check_exp((ir)->o == IR_KNUM || (ir)->o == IR_KINT64, &(ir)[1].tv)
 #define ir_kptr(ir) \
-  check_exp((ir)->o == IR_KPTR || (ir)->o == IR_KKPTR, mref((ir)->ptr, void))
+  check_exp((ir)->o == IR_KPTR || (ir)->o == IR_KKPTR, \
+    mref((ir)[LJ_GC64].ptr, void))
 
 /* A store or any other op with a non-weak guard has a side-effect. */
 static LJ_AINLINE int ir_sideeff(IRIns *ir)