From 4c46806b3940e7545204deb3144e92328cb4e1f1 Mon Sep 17 00:00:00 2001
From: Jean Privat <jean@pryen.org>
Date: Mon, 10 Aug 2009 13:14:54 -0400
Subject: [PATCH] icode: iroutine knows its local registers

iroutine inlining is also adapted to only duplicate local registers.

Signed-off-by: Jean Privat <jean@pryen.org>
---
 src/icode/icode_base.nit    |    3 +++
 src/icode/icode_builder.nit |    4 +++-
 src/icode/icode_tools.nit   |   35 +++++++++++++++++++++++------------
 3 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/src/icode/icode_base.nit b/src/icode/icode_base.nit
index 5c265e6..f15b4a0 100644
--- a/src/icode/icode_base.nit
+++ b/src/icode/icode_base.nit
@@ -51,6 +51,9 @@ class IRoutine
 	# The closure declared
 	readable writable var _closure_decls: nullable Sequence[IClosureDecl] = null
 
+	# The local variables (excluding params and result)
+	readable var _registers: Set[IRegister] = new ArraySet[IRegister]
+
 	# The result of the routine
 	readable var _result: nullable IRegister
 
diff --git a/src/icode/icode_builder.nit b/src/icode/icode_builder.nit
index c7cfe59..d1dd617 100644
--- a/src/icode/icode_builder.nit
+++ b/src/icode/icode_builder.nit
@@ -184,7 +184,9 @@ class ICodeBuilder
 	# Get a new register
 	fun new_register(s: MMType): IRegister
 	do
-		return new IRegister(s)
+		var r = new IRegister(s)
+		iroutine.registers.add(r)
+		return r
 	end
 
 	# The module where classes and types are extracted
diff --git a/src/icode/icode_tools.nit b/src/icode/icode_tools.nit
index 349ed1a..0b48de9 100644
--- a/src/icode/icode_tools.nit
+++ b/src/icode/icode_tools.nit
@@ -97,37 +97,48 @@ redef class ICodeBuilder
 	do
 		var d = new ICodeDupContext
 		assert args.length == routine.params.length
+
+		# Fill register duplicate association
+		var dico = d._registers
+		var res = routine.result
+		if res != null then
+			var res2 = new_register(res.stype)
+			dico[res] = res2
+			res = res2
+		end
+		for reg in routine.registers do
+			assert not dico.has_key(reg)
+			dico[reg] = new_register(reg.stype)
+		end
 		for i in [0..args.length[ do
 			# FIXME The following assumes that params are readonly.
 			# The alternative is safe but add one move :/
-			d._registers[routine.params[i]] = args[i]
-			#seq.icodes.add(new IMove(d.dup_ireg(routine.params[i]), args[i]))
+			dico[routine.params[i]] = args[i]
+			#seq.icodes.add(new IMove(dico[routine.params[i]]), args[i]))
 		end
+
+		# Process inlining
 		seq.icodes.add(routine.body.dup_with(d))
-		var r = routine.result
-		if r != null then r = d.dup_ireg(r)
-		return r
+		return res
 	end
 end
 
 # This class stores reference to allow correct duplication of icodes
 private class ICodeDupContext
-	# Duplicate one register
-	# Subsequent invocation will return the same register
+	# Return the correct register
+	# * a duplicate of the local register 'r' of the inlined iroutine
+	# * 'r' else (it is a register of the caller iroutine)
 	fun dup_ireg(r: IRegister): IRegister
 	do
 		var rs = _registers
 		if rs.has_key(r) then
 			return rs[r]
 		else
-			var r2 = new IRegister(r.stype)
-			rs[r] = r2
-			return r2
+			return r
 		end
 	end
 
-	# Duplicate a bunch of registers
-	# Subsequent invocation will return the same registers
+	# Return a correct bunch of registers
 	fun dup_iregs(regs: Sequence[IRegister]): Sequence[IRegister]
 	do
 		var a = new Array[IRegister].with_capacity(regs.length)
-- 
1.7.9.5