From e6e760ca9f021703551d2093697908644ab76829 Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Wed, 9 Oct 2013 20:34:40 +0200
Subject: [PATCH] Compile getfenv(0).

---
 src/lib_base.c    |  2 +-
 src/lj_asm.c      | 13 ++++++++++++-
 src/lj_ffrecord.c | 13 +++++++++++++
 src/lj_ir.h       |  2 ++
 src/lj_opt_fold.c |  3 +++
 5 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/src/lib_base.c b/src/lib_base.c
index 1665faee..a19926a7 100644
--- a/src/lib_base.c
+++ b/src/lib_base.c
@@ -136,7 +136,7 @@ LJLIB_ASM(setmetatable)		LJLIB_REC(.)
   return FFH_RES(1);
 }
 
-LJLIB_CF(getfenv)
+LJLIB_CF(getfenv)		LJLIB_REC(.)
 {
   GCfunc *fn;
   cTValue *o = L->base;
diff --git a/src/lj_asm.c b/src/lj_asm.c
index 0d6875a6..fb364c74 100644
--- a/src/lj_asm.c
+++ b/src/lj_asm.c
@@ -699,7 +699,7 @@ static void ra_left(ASMState *as, Reg dest, IRRef lref)
 	emit_loadu64(as, dest, ir_kint64(ir)->u64);
 	return;
 #endif
-      } else {
+      } else if (ir->o != IR_KPRI) {
 	lua_assert(ir->o == IR_KINT || ir->o == IR_KGC ||
 		   ir->o == IR_KPTR || ir->o == IR_KKPTR || ir->o == IR_KNULL);
 	emit_loadi(as, dest, ir->i);
@@ -1191,6 +1191,16 @@ static void asm_newref(ASMState *as, IRIns *ir)
   asm_tvptr(as, ra_releasetmp(as, ASMREF_TMP1), ir->op2);
 }
 
+static void asm_lref(ASMState *as, IRIns *ir)
+{
+  Reg r = ra_dest(as, ir, RSET_GPR);
+#if LJ_TARGET_X86ORX64
+  ra_left(as, r, ASMREF_L);
+#else
+  ra_leftov(as, r, ASMREF_L);
+#endif
+}
+
 /* -- Calls --------------------------------------------------------------- */
 
 /* Collect arguments from CALL* and CARG instructions. */
@@ -1624,6 +1634,7 @@ static void asm_ir(ASMState *as, IRIns *ir)
   case IR_UREFO: case IR_UREFC: asm_uref(as, ir); break;
   case IR_FREF: asm_fref(as, ir); break;
   case IR_STRREF: asm_strref(as, ir); break;
+  case IR_LREF: asm_lref(as, ir); break;
 
   /* Loads and stores. */
   case IR_ALOAD: case IR_HLOAD: case IR_ULOAD: case IR_VLOAD:
diff --git a/src/lj_ffrecord.c b/src/lj_ffrecord.c
index 29916e71..de74a3ec 100644
--- a/src/lj_ffrecord.c
+++ b/src/lj_ffrecord.c
@@ -422,6 +422,19 @@ static void LJ_FASTCALL recff_xpcall(jit_State *J, RecordFFData *rd)
   }  /* else: Interpreter will throw. */
 }
 
+static void LJ_FASTCALL recff_getfenv(jit_State *J, RecordFFData *rd)
+{
+  TRef tr = J->base[0];
+  /* Only support getfenv(0) for now. */
+  if (tref_isint(tr) && tref_isk(tr) && IR(tref_ref(tr))->i == 0) {
+    TRef trl = emitir(IRT(IR_LREF, IRT_THREAD), 0, 0);
+    J->base[0] = emitir(IRT(IR_FLOAD, IRT_TAB), trl, IRFL_THREAD_ENV);
+    return;
+  }
+  recff_nyiu(J);
+  UNUSED(rd);
+}
+
 /* -- Math library fast functions ----------------------------------------- */
 
 static void LJ_FASTCALL recff_math_abs(jit_State *J, RecordFFData *rd)
diff --git a/src/lj_ir.h b/src/lj_ir.h
index f50132ea..bd2723cd 100644
--- a/src/lj_ir.h
+++ b/src/lj_ir.h
@@ -97,6 +97,7 @@
   _(UREFC,	LW, ref, lit) \
   _(FREF,	R , ref, lit) \
   _(STRREF,	N , ref, ref) \
+  _(LREF,	L , ___, ___) \
   \
   /* Loads and Stores. These must be in the same order. */ \
   _(ALOAD,	L , ref, ___) \
@@ -193,6 +194,7 @@ IRFPMDEF(FPMENUM)
   _(STR_LEN,	offsetof(GCstr, len)) \
   _(FUNC_ENV,	offsetof(GCfunc, l.env)) \
   _(FUNC_PC,	offsetof(GCfunc, l.pc)) \
+  _(THREAD_ENV,	offsetof(lua_State, env)) \
   _(TAB_META,	offsetof(GCtab, metatable)) \
   _(TAB_ARRAY,	offsetof(GCtab, array)) \
   _(TAB_NODE,	offsetof(GCtab, node)) \
diff --git a/src/lj_opt_fold.c b/src/lj_opt_fold.c
index 2ca04a69..a3c8723b 100644
--- a/src/lj_opt_fold.c
+++ b/src/lj_opt_fold.c
@@ -2104,6 +2104,7 @@ LJFOLDF(fwd_href_tdup)
 ** an aliased table, as it may invalidate all of the pointers and fields.
 ** Only HREF needs the NEWREF check -- AREF and HREFK already depend on
 ** FLOADs. And NEWREF itself is treated like a store (see below).
+** LREF is constant (per trace) since coroutine switches are not inlined.
 */
 LJFOLD(FLOAD TNEW IRFL_TAB_ASIZE)
 LJFOLDF(fload_tab_tnew_asize)
@@ -2221,6 +2222,8 @@ LJFOLDF(fload_cdata_ptr_int64_cnew)
 }
 
 LJFOLD(FLOAD any IRFL_STR_LEN)
+LJFOLD(FLOAD any IRFL_FUNC_ENV)
+LJFOLD(FLOAD any IRFL_THREAD_ENV)
 LJFOLD(FLOAD any IRFL_CDATA_CTYPEID)
 LJFOLD(FLOAD any IRFL_CDATA_PTR)
 LJFOLD(FLOAD any IRFL_CDATA_INT)