add relational operations to stack machine

1 files changed, 69 insertions, 1 deletions

diff --git a/design/stack_machine.v b/design/stack_machine.v
index b5c56e6..687168a 100644
--- a/design/stack_machine.v
+++ b/design/stack_machine.v
@@ -54,8 +54,13 @@ module stack_machine_new
 
    reg [31:0] 	      r0;
    reg [31:0] 	      r1;
-   reg [31:0] 	      im;
 
+   wire signed [31:0] r0s;
+   wire signed [31:0] r1s;
+   assign r0s = r0;
+   assign r1s = r1;
+
+   reg [31:0] 	      im;
    reg 		      im_initialized;
 
    parameter STEP_LOADING_INSTRUCTION = 1'b0;
@@ -243,6 +248,42 @@ module stack_machine_new
    assign instr_drop = !set_im && !use_im && stack_shrinks_by_1 &&
 		       instruction[11:0] == 12'd4;
 
+   wire 	      instr_eq;
+   assign instr_eq = !set_im && !use_im && stack_shrinks_by_1 &&
+		     instruction[11:0] == 12'd7;
+
+   wire 	      instr_lt;
+   assign instr_lt = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd8;
+
+   wire 	      instr_ult;
+   assign instr_ult = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd9;
+
+   wire 	      instr_le;
+   assign instr_le = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd10;
+
+   wire 	      instr_ule;
+   assign instr_ule = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd11;
+
+   wire 	      instr_gt;
+   assign instr_gt = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd12;
+
+   wire 	      instr_ugt;
+   assign instr_ugt = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd13;
+
+   wire 	      instr_ge;
+   assign instr_ge = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd14;
+
+   wire 	      instr_uge;
+   assign instr_uge = !set_im && !use_im && stack_shrinks_by_1 &&
+		       instruction[11:0] == 12'd15;
+
    wire 	      instr_ret;
    assign instr_ret = !set_im && !use_im && stack_shrinks_by_1 &&
 		      instruction[11:0] == 12'b000010000000;
@@ -583,6 +624,33 @@ module stack_machine_new
 		   `SET_PC(im_effective);
 	      end
 
+	      if (instr_eq && arithmetic_uncompleted)
+		r1 <= r0 == r1;
+
+	      if (instr_lt && arithmetic_uncompleted)
+		r1 <= r0s < r1s;
+
+	      if (instr_ult && arithmetic_uncompleted)
+		r1 <= r0 < r1;
+
+	      if (instr_le && arithmetic_uncompleted)
+		r1 <= r0s <= r1s;
+
+	      if (instr_ule && arithmetic_uncompleted)
+		r1 <= r0 <= r1;
+
+	      if (instr_gt && arithmetic_uncompleted)
+		r1 <= r0s > r1s;
+
+	      if (instr_ugt && arithmetic_uncompleted)
+		r1 <= r0 > r1;
+
+	      if (instr_ge && arithmetic_uncompleted)
+		r1 <= r0s >= r1s;
+
+	      if (instr_uge && arithmetic_uncompleted)
+		r1 <= r0 >= r1;
+
 	      if (instr_ret && arithmetic_uncompleted) begin
 		 r1 <= r0;
 		 `SET_PC(r1);