From 2f4337f027ec97dd93642ea2db70873e9192fb3b Mon Sep 17 00:00:00 2001
From: Tristan Gingold
Date: Sun, 7 Dec 2014 11:40:58 +0100
Subject: Add perf02 (performance issue).

---
 testsuite/gna/perf02/shr_141.vhd | 46 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 testsuite/gna/perf02/shr_141.vhd

(limited to 'testsuite/gna/perf02/shr_141.vhd')

diff --git a/testsuite/gna/perf02/shr_141.vhd b/testsuite/gna/perf02/shr_141.vhd
new file mode 100644
index 0000000..25ffac5
--- /dev/null
+++ b/testsuite/gna/perf02/shr_141.vhd
@@ -0,0 +1,46 @@
+library ieee;
+use ieee.std_logic_1164.all;
+
+library ieee;
+use ieee.numeric_std.all;
+
+entity shr_141 is
+	port (
+		output : out std_logic_vector(31 downto 0);
+		input : in  std_logic_vector(31 downto 0);
+		shift : in  std_logic_vector(5 downto 0);
+		padding : in  std_logic
+	);
+end shr_141;
+
+architecture augh of shr_141 is
+
+	signal tmp_padding : std_logic;
+	signal tmp_result  : std_logic_vector(32 downto 0);
+
+	-- Little utility functions to make VHDL syntactically correct
+	--   with the syntax to_integer(unsigned(vector)) when 'vector' is a std_logic.
+	--   This happens when accessing arrays with <= 2 cells, for example.
+
+	function to_integer(B: std_logic) return integer is
+		variable V: std_logic_vector(0 to 0);
+	begin
+		V(0) := B;
+		return to_integer(unsigned(V));
+	end;
+
+	function to_integer(V: std_logic_vector) return integer is
+	begin
+		return to_integer(unsigned(V));
+	end;
+
+begin
+
+	-- Temporary signals
+	tmp_padding <= padding;
+	tmp_result <= std_logic_vector(shift_right( unsigned(padding & input), to_integer(shift) ));
+
+	-- The output
+	output <= tmp_result(31 downto 0);
+
+end architecture;
-- 
cgit