From 40dadcdacbc9a931cf56585df393ee3b25122332 Mon Sep 17 00:00:00 2001
From: Jean Privat <jean@pryen.org>
Date: Tue, 6 Oct 2015 21:50:45 -0400
Subject: [PATCH] interpreter&vm: handle multi-iterator

Signed-off-by: Jean Privat <jean@pryen.org>
---
 src/interpreter/naive_interpreter.nit |   58 +++++++++++++++++++--------------
 src/ssa.nit                           |   14 ++++----
 src/vm/variables_numbering.nit        |   25 +++++++-------
 3 files changed, 56 insertions(+), 41 deletions(-)

diff --git a/src/interpreter/naive_interpreter.nit b/src/interpreter/naive_interpreter.nit
index da7b288..f2aabe4 100644
--- a/src/interpreter/naive_interpreter.nit
+++ b/src/interpreter/naive_interpreter.nit
@@ -1757,37 +1757,47 @@ end
 redef class AForExpr
 	redef fun stmt(v)
 	do
-		var col = v.expr(self.n_expr)
-		if col == null then return
-		if col.mtype isa MNullType then fatal(v, "Receiver is null")
+		var iters = new Array[Instance]
+
+		for g in n_groups do
+			var col = v.expr(g.n_expr)
+			if col == null then return
+			if col.mtype isa MNullType then fatal(v, "Receiver is null")
+
+			var iter = v.callsite(g.method_iterator, [col]).as(not null)
+			iters.add iter
+		end
 
-		#self.debug("col {col}")
-		var iter = v.callsite(method_iterator, [col]).as(not null)
-		#self.debug("iter {iter}")
 		loop
-			var isok = v.callsite(method_is_ok, [iter]).as(not null)
-			if not isok.is_true then break
-			if self.variables.length == 1 then
-				var item = v.callsite(method_item, [iter]).as(not null)
-				#self.debug("item {item}")
-				v.write_variable(self.variables.first, item)
-			else if self.variables.length == 2 then
-				var key = v.callsite(method_key, [iter]).as(not null)
-				v.write_variable(self.variables[0], key)
-				var item = v.callsite(method_item, [iter]).as(not null)
-				v.write_variable(self.variables[1], item)
-			else
-				abort
+			for g in n_groups, iter in iters do
+				var isok = v.callsite(g.method_is_ok, [iter]).as(not null)
+				if not isok.is_true then break label
+				if g.variables.length == 1 then
+					var item = v.callsite(g.method_item, [iter]).as(not null)
+					#self.debug("item {item}")
+					v.write_variable(g.variables.first, item)
+				else if g.variables.length == 2 then
+					var key = v.callsite(g.method_key, [iter]).as(not null)
+					v.write_variable(g.variables[0], key)
+					var item = v.callsite(g.method_item, [iter]).as(not null)
+					v.write_variable(g.variables[1], item)
+				else
+					abort
+				end
 			end
 			v.stmt(self.n_block)
 			if v.is_escape(self.break_mark) then break
 			v.is_escape(self.continue_mark) # Clear the break
 			if v.is_escaping then break
-			v.callsite(method_next, [iter])
-		end
-		var method_finish = self.method_finish
-		if method_finish != null then
-			v.callsite(method_finish, [iter])
+			for g in n_groups, iter in iters do
+				v.callsite(g.method_next, [iter])
+			end
+		end label
+		for g in n_groups, iter in iters do
+			var method_finish = g.method_finish
+			if method_finish != null then
+				v.callsite(method_finish, [iter])
+			end
 		end
 	end
 end
diff --git a/src/ssa.nit b/src/ssa.nit
index 65a4de6..dbaac2e 100644
--- a/src/ssa.nit
+++ b/src/ssa.nit
@@ -1117,15 +1117,17 @@ redef class AForExpr
 
 		# The beginning of the block is the first instruction
 		var block = new BasicBlock
-		block.first = self.n_expr
+		block.first = self.n_groups.first.n_expr
 		block.last = self.n_block.as(not null)
 
-		# Visit the test of the if
-		self.n_expr.generate_basic_blocks(ssa, block)
+		for g in n_groups do
+			# Visit the test of the if
+			g.n_expr.generate_basic_blocks(ssa, block)
 
-		# Collect the variables declared in the for
-		for v in variables do
-			ssa.propdef.variables.add(v)
+			# Collect the variables declared in the for
+			for v in g.variables do
+				ssa.propdef.variables.add(v)
+			end
 		end
 
 		old_block.link(block)
diff --git a/src/vm/variables_numbering.nit b/src/vm/variables_numbering.nit
index d01b390..75bff69 100644
--- a/src/vm/variables_numbering.nit
+++ b/src/vm/variables_numbering.nit
@@ -254,18 +254,21 @@ end
 redef class AForExpr
 	redef fun numbering(v, position)
 	do
-		# Give a position to each variable declared in the header of the for
-		if self.variables.length == 1 then
-			self.variables.first.position = position
-			self.variables[0].position = position
-			position += 1
-		else if self.variables.length == 2 then
-			self.variables[0].position = position
-			position += 1
-			self.variables[1].position = position
-			position += 1
+		for g in n_groups do
+			# Give a position to each variable declared in the header of the for
+			if g.variables.length == 1 then
+				g.variables.first.position = position
+				g.variables[0].position = position
+				position += 1
+			else if g.variables.length == 2 then
+				g.variables[0].position = position
+				position += 1
+				g.variables[1].position = position
+				position += 1
+			end
+			position = v.numbering(self.n_block, position)
 		end
-		return v.numbering(self.n_block, position)
+		return position
 	end
 end
 
-- 
1.7.9.5