From fee4290fa17758f37b9bb7d3906f21e4406a3326 Mon Sep 17 00:00:00 2001
From: James Roseborough <james.roseborough@luaj.org>
Date: Mon, 3 Sep 2012 05:41:38 +0000
Subject: [PATCH] Compiler for lua 5.2 fixes.

---
 src/core/org/luaj/vm2/compiler/FuncState.java | 27 ++++++++++---------
 src/core/org/luaj/vm2/compiler/LexState.java  | 21 +++++++++------
 2 files changed, 28 insertions(+), 20 deletions(-)

diff --git a/src/core/org/luaj/vm2/compiler/FuncState.java b/src/core/org/luaj/vm2/compiler/FuncState.java
index b48deb91..f8bddcb9 100644
--- a/src/core/org/luaj/vm2/compiler/FuncState.java
+++ b/src/core/org/luaj/vm2/compiler/FuncState.java
@@ -28,6 +28,7 @@ import org.luaj.vm2.LocVars;
 import org.luaj.vm2.Lua;
 import org.luaj.vm2.LuaNil;
 import org.luaj.vm2.LuaTable;
+import org.luaj.vm2.LuaUserdata;
 import org.luaj.vm2.Prototype;
 import org.luaj.vm2.Upvaldesc;
 import org.luaj.vm2.LuaString;
@@ -511,8 +512,11 @@ public class FuncState extends LuaC {
 		return this.addk((b ? LuaValue.TRUE : LuaValue.FALSE));
 	}
 
+	static final LuaUserdata NIL_PROXY = new LuaUserdata(LuaValue.NIL);
+
 	int nilK() {
-		return this.addk(LuaValue.NIL);
+		/* cannot use nil as key; instead use table itself to represent nil */
+		return this.addk(NIL_PROXY);
 	}
 
 	void setreturns(expdesc e, int nresults) {
@@ -674,19 +678,22 @@ public class FuncState extends LuaC {
 	int exp2RK(expdesc e) {
 		this.exp2val(e);
 		switch (e.k) {
-		case LexState.VKNUM:
 		case LexState.VTRUE:
 		case LexState.VFALSE:
 		case LexState.VNIL: {
 			if (this.nk <= MAXINDEXRK) { /* constant fit in RK operand? */
 				e.u.info = (e.k == LexState.VNIL) ? this.nilK()
-						: (e.k == LexState.VKNUM) ? this.numberK(e.u.nval())
 								: this.boolK((e.k == LexState.VTRUE));
 				e.k = LexState.VK;
 				return RKASK(e.u.info);
 			} else
 				break;
 		}
+		case LexState.VKNUM: {
+		      e.u.info = this.numberK(e.u.nval());
+		      e.k = LexState.VK;
+		      /* go through */			
+		}
 		case LexState.VK: {
 			if (e.u.info <= MAXINDEXRK) /* constant fit in argC? */
 				return RKASK(e.u.info);
@@ -767,21 +774,17 @@ public class FuncState extends LuaC {
 		int pc; /* pc of last jump */
 		this.dischargevars(e);
 		switch (e.k) {
+		case LexState.VJMP: {
+			this.invertjump(e);
+			pc = e.u.info;
+			break;
+		}
 		case LexState.VK:
 		case LexState.VKNUM:
 		case LexState.VTRUE: {
 			pc = LexState.NO_JUMP; /* always true; do nothing */
 			break;
 		}
-		case LexState.VFALSE: {
-			pc = this.jump(); /* always jump */
-			break;
-		}
-		case LexState.VJMP: {
-			this.invertjump(e);
-			pc = e.u.info;
-			break;
-		}
 		default: {
 			pc = this.jumponcond(e, 0);
 			break;
diff --git a/src/core/org/luaj/vm2/compiler/LexState.java b/src/core/org/luaj/vm2/compiler/LexState.java
index fd3ec7fb..9ec1381f 100644
--- a/src/core/org/luaj/vm2/compiler/LexState.java
+++ b/src/core/org/luaj/vm2/compiler/LexState.java
@@ -402,7 +402,7 @@ public class LexState {
 		while (true) {
 			if (check_next(expo))
 				check_next("+-");
-			if(isxdigit(current))
+			if(isxdigit(current) || current == '.')
 				save_and_next();
 			else
 				break;
@@ -699,7 +699,6 @@ public class LexState {
 			lookahead.token = TK_EOS; /* and discharge it */
 		} else
 			t.token = llex(t.seminfo); /* read next token */
-		System.out.println("----- next t.token " + t.token + " (" + (t.token!=0? txtToken(t.token): "-")+") "+ linenumber );
 	}
 
 	void lookahead() {
@@ -1034,7 +1033,7 @@ public class LexState {
 	*/
 	void breaklabel () {
 		LuaString n = LuaString.valueOf("break");
-		int l = newlabelentry(LuaC.grow(dyd.label, dyd.n_label+1), dyd.n_label++, n, 0, fs.pc);
+		int l = newlabelentry(dyd.label=LuaC.grow(dyd.label, dyd.n_label+1), dyd.n_label++, n, 0, fs.pc);
 		findgotos(dyd.label[l]);
 	}
 
@@ -1787,10 +1786,15 @@ public class LexState {
 		this.block();
 		fs.leaveblock(); /* end of scope for declared variables */
 		fs.patchtohere(prep);
-		endfor = (isnum) ? fs.codeAsBx(Lua.OP_FORLOOP, base, NO_JUMP) : fs
-				.codeABC(Lua.OP_TFORLOOP, base, 0, nvars);
-		fs.fixline(line); /* pretend that `Lua.OP_FOR' starts the loop */
-		fs.patchlist((isnum ? endfor : fs.jump()), prep + 1);
+		if (isnum)  /* numeric for? */
+			endfor = fs.codeAsBx(Lua.OP_FORLOOP, base, NO_JUMP);
+		else {  /* generic for */
+			fs.codeABC(Lua.OP_TFORCALL, base, 0, nvars);
+			fs.fixline(line);
+			endfor = fs.codeAsBx(Lua.OP_TFORLOOP, base + 2, NO_JUMP);
+		}
+		fs.patchlist(endfor, prep + 1);
+		fs.fixline(line);
 	}
 
 
@@ -1990,7 +1994,6 @@ public class LexState {
 		FuncState fs = this.fs;
 		expdesc e = new expdesc();
 		int first, nret; /* registers with returned values */
-		this.next(); /* skip RETURN */
 		if (block_follow(true) || this.t.token == ';')
 			first = nret = 0; /* return no values */
 		else {
@@ -2014,10 +2017,12 @@ public class LexState {
 			}
 		}
 		fs.ret(first, nret);
+		testnext(';');  /* skip optional semicolon */
 	}
 
 	void statement() {
 		int line = this.linenumber; /* may be needed for error messages */
+		enterlevel();
 		switch (this.t.token) {
 		case ';': { /* stat -> ';' (empty statement) */
 			next(); /* skip ';' */