Adds a general conditional jump instruction (#44)

* Adds pseudo instructions for all comparisons
* Updates example programs
* Updates bf compiler
* Updates README

README.md

@@ -36,7 +36,7 @@ A couple of examples illustrating the language can be found in the `asm/` folder
 ### Instruction set
 
 #### Real instructions
-
+``
 |Instruction|Arguments|16 bit representation |Description|
 |-----------|---------|-------------------------|-------------|
 |`MVR`| `D, S, V`       | `VVVVVVVVSSDD0000` | Add a sign-extended byte to value at source register and move it to destination register|
@@ -48,7 +48,7 @@ A couple of examples illustrating the language can be found in the `asm/` folder
 |`ATH`| `D, S, O, M, B` | `BBBMOOOOSSDD0100` | Perform an arithmetic operation on the source and destination registers. O specifies the operation (listed below) and M is the mode, where 0 = place result in destination register and 1 = place result in source register. If the instruction is right or left shift then B specifies the shifting value|
 |`CAL`| `D`             | `XXXXXXXXXXDD0101` | Call a function in memory pointed at by the destination register|
 |`RET`|                 | `XXXXXXXXXXXX0110` | Return from function|
-|`JLT`| `D, S`          | `XXXXXXXXSSDD0111` | Jump to memory address pointed at by the source register, if value in the A register is less than value in destination register|
+|`JCP`| `D, S, A, O`    | `XXXOOOAASSDD0111` | Jump to memory address pointed at by the address register, depending on the comparison specified by the O operation of the destination register and the source register. Operation table specified below.|
 |`PSH`| `S`             | `XXXXXXXXSSXX1000` | Push the value in source register onto the stack|
 |`POP`| `D`             | `XXXXXXXXXXDD1001` | Pop the stack into the destination register|
 |`SYS`|                 | `XXXXXXXXXXXX1010` | Perform a system call. This is described below in more detail.|
@@ -89,9 +89,14 @@ Pseudo instructions are prepocessed by the assembler and expanded into combinati
 |`NOT`      | `D`       |1                | Binary not (invert) the destination|
 |`LDV16`    | `D, V`    |2                | Load a 16 bit value into destination|
 |`SWP`      | `D, S`    |3                | Swap the values in the source and destination registers|
-|`JGE`      | `D, A`    |4                | Jump to address A if value in destination register is greater than or equal to the A register. Can potentially mutate all registers except A and destination|
-|`JEQ`      | `D, A`    |11               | Jump to address A if value in destination register is equal to the A register. Can potentially mutate all registers except A and destination|
-|`JNE`      | `D, A`    |14               | Jump to address A if value in destination register is not equal to the A register. Can potentially mutate all registers except A and destination|
+|`JEQ`      | `D, S, A` |1                | Jump to address A if value in destination register is equal to the source register.|
+|`JNE`      | `D, S, A` |1                | Jump to address A if value in destination register is not equal to the source register.|
+|`JLT`      | `D, S, A` |1                | Jump to address A if value in destination register is less than the source register.|
+|`JGT`      | `D, S, A` |1                | Jump to address A if value in destination register is greater than the source register.|
+|`JLE`      | `D, S, A` |1                | Jump to address A if value in destination register is less than or equal to the source register.|
+|`JGE`      | `D, S, A` |1                | Jump to address A if value in destination register is greater than or equal to the source register.|
+|`JZE`      | `D, S, A` |1                | Jump to address A if value in destination register is zero.|
+|`JNZ`      | `D, S, A` |1                | Jump to address A if value in destination register is not zero.|
 
 
 #### Arithmetic Operation table

asm/factorial.asm

@@ -20,7 +20,7 @@ factorial:
     pop A
     ldv B, 3
     ldv D, done:
-    jlt B, D
+    JLT A, B, D
 
     psh a
     psh b

asm/get-name.asm

@@ -18,7 +18,7 @@ get_name:
   ldv d, get_name:
   mov a, b
   ldv b, 1
-  jlt b, d              ; if a < 1, loop
+  jlt a, b, d              ; if a < 1, loop
 
   ;;;;; Place character into memory ;;;;
   ldv b, .name          ; get the start address of name
@@ -39,7 +39,7 @@ get_name:
 
   ;;;;; Got all the characters? ;;;;;;;;
   ldv c, final_zero:
-  jlt b, c              ; if (a < b) = (name_max < name_pointer), we are done
+  jlt a, b, c              ; if (a < b) = (name_max < name_pointer), we are done
   ldv c, get_name:      ; otherwise jump back to the beginning to get the next character
   jmr c
 

asm/loop-until-a-is-pressed.asm

@@ -27,6 +27,6 @@ main:
 
   loop:
     cal D
-    jne B, C
+    jne A, B, C
 
   hlt

src/assembler/assembler/instruction-encoder.js

@@ -6,7 +6,8 @@ const {
   SOURCE_SHIFT,
   LONG_ADDRESS_SHIFT,
   OFFSET_SHIFT,
-  ADDRESS_SHIFT,
+
+  JUMP,
 
   ARITHMETIC_MODE_SHIFT,
   OPERATION_SHIFT,
@@ -34,7 +35,7 @@ module.exports = {
   STR: (args) => opcodes.STR | (reg[args[0]] << DESTINATION_SHIFT) | (reg[args[1]] << SOURCE_SHIFT) | (args.length > 2 ? (args[2] << OFFSET_SHIFT) : 0),
   ATH: (args) => opcodes.ATH | (reg[args[0]] << DESTINATION_SHIFT) | (reg[args[1]] << SOURCE_SHIFT) | (args[2] << OPERATION_SHIFT) | (args[3] << ARITHMETIC_MODE_SHIFT) | (args[4] << BITWISE_SHIFT_SHIFT),
   CAL: (args) => opcodes.CAL | (reg[args[0]] << DESTINATION_SHIFT),
-  JLT: (args) => opcodes.JLT | (reg[args[0]] << DESTINATION_SHIFT) | (reg[args[1]] << SOURCE_SHIFT),
+  JCP: (args) => opcodes.JCP | (reg[args[0]] << JUMP.R1) | (reg[args[1]] << JUMP.R2) | (reg[args[2]] << JUMP.AR) | (args[3] << JUMP.OP),
   PSH: (args) => opcodes.PSH | (reg[args[0]] << SOURCE_SHIFT),
   POP: (args) => opcodes.POP | (reg[args[0]] << DESTINATION_SHIFT),
   JMP: (args) => opcodes.JMP | (reg[args[0]] << DESTINATION_SHIFT) | (args[1] << LONG_ADDRESS_SHIFT),

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JEQ.js

@@ -1,43 +1,7 @@
-const {
-  getInstructionArguments,
-  uniqueLabel,
-  getUsableRegister
-} = require('../../../../utils');
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
 
 module.exports = (instruction) => {
-  const [source, addressRegister] = getInstructionArguments(instruction);
-  const mutableRegister = getUsableRegister(source, addressRegister);
-
-  const firstCheck = uniqueLabel();
-  const equal = uniqueLabel();
-  const notEqual = uniqueLabel();
-
-  return [
-    `PSH ${mutableRegister}`,                   // Push mr [mr]
-
-    `PSH ${addressRegister}`,                   // Push ar [ar, mr]
-    `LDV16 ${addressRegister}, ${firstCheck}`,
-    `LDV16 ${mutableRegister}, ${notEqual}`,
-
-    `JGE ${source}, ${addressRegister}`,
-    `JMR ${mutableRegister}`,
-
-    `${firstCheck}`,
-    `LDV16 ${addressRegister}, ${equal}`,
-    `SWP A, ${source}`,
-    `JGE ${source}, ${addressRegister}`,
-
-    `SWP A, ${source}`,
-    `JMR ${mutableRegister}`,
-
-    `${equal}`,
-    `SWP A, ${source}`,
-    `POP ${addressRegister}`,                 // Pop ar [mr]
-    `POP ${mutableRegister}`,                 // Pop mr []
-    `JMR ${addressRegister}`,
-
-    `${notEqual}`,
-    `POP ${addressRegister}`,                 // Pop ar [mr]
-    `POP ${mutableRegister}`                  // Pop mr []
-  ];
-}
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.EQ}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JGE.js

@@ -1,24 +1,7 @@
-const {
-  getInstructionArguments,
-  uniqueLabel,
-  getUsableRegister
-} = require('../../../../utils');
-
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
 
 module.exports = (instruction) => {
-  const [source, addressRegister] = getInstructionArguments(instruction);
-  const lessThan = uniqueLabel();
-  const mutableRegister = getUsableRegister(source, addressRegister);
-
-  return [
-    `PSH ${mutableRegister}`,
-    `LDV16 ${mutableRegister}, ${lessThan}`,
-
-    `JLT ${source}, ${mutableRegister}`,
-    `POP ${mutableRegister}`,
-    `JMR ${addressRegister}`,
-
-    `${lessThan}`,
-    `POP ${mutableRegister}`
-  ];
-}
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.GTE}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JGT.js

@@ -0,0 +1,7 @@
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
+
+module.exports = (instruction) => {
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.GT}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JLE.js

@@ -0,0 +1,7 @@
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
+
+module.exports = (instruction) => {
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.JLE}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JLT.js

@@ -0,0 +1,7 @@
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
+
+module.exports = (instruction) => {
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.LT}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JNE.js

@@ -1,23 +1,7 @@
-const {
-  getInstructionArguments,
-  uniqueLabel,
-  getUsableRegister
-} = require('../../../../utils');
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
 
 module.exports = (instruction) => {
-  const [source, addressRegister] = getInstructionArguments(instruction);
-  const equal = uniqueLabel();
-  const mutableRegister = getUsableRegister(source, addressRegister);
-
-  return [
-    `PSH ${mutableRegister}`,
-    `LDV16 ${mutableRegister}, ${equal}`,
-
-    `JEQ ${source}, ${mutableRegister}`,
-    `POP ${mutableRegister}`,
-    `JMR ${addressRegister}`,
-
-    `${equal}`,
-    `POP ${mutableRegister}`
-  ];
-}
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.NEQ}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JNZ.js

@@ -0,0 +1,7 @@
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
+
+module.exports = (instruction) => {
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.NZE}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/JZE.js

@@ -0,0 +1,7 @@
+const { getInstructionArguments } = require('../../../../utils');
+const { JUMP } = require('../../../../../../constants');
+
+module.exports = (instruction) => {
+  const [r1, r2, addressRegister] = getInstructionArguments(instruction);
+  return [`JCP ${r1}, ${r2}, ${addressRegister}, ${JUMP.ZER}`];
+};

src/assembler/preprocessor/stages/pseudo-instructions/expanders/conditional/index.js

@@ -1,9 +1,19 @@
 const JEQ = require('./JEQ');
-const JGE = require('./JGE');
 const JNE = require('./JNE');
+const JLT = require('./JLT');
+const JGT = require('./JGT');
+const JLE = require('./JLE');
+const JGE = require('./JGE');
+const JZE = require('./JZE');
+const JNZ = require('./JNZ');
 
 module.exports = {
   JEQ,
+  JNE,
+  JLT,
+  JGT,
+  JLE,
   JGE,
-  JNE
+  JZE,
+  JNZ
 };

src/compilers/bf/asm/header.js

@@ -46,7 +46,7 @@ input:
   mov A, B            ; swap A and B
   ldv B, 1            ; load 1 into B for comparison
   ldv C, input:       ; load the input address into C
-  jlt B, C            ; if A < 1(B), loop back to input
+  jlt A, B, C            ; if A < 1(B), loop back to input
   psh A               ; push the character into stack
   ldv16 A, .offset    ; Same procedure as inc_mem_ptr, except just set the value directly
   ldr B, A

src/compilers/bf/asm/loop-end.js

@@ -8,6 +8,6 @@ ldr B, A            ; B = value at [memory + offset]
 mov A, B            ; A = value at [memory + offset]
 ldv B, 1            ; Set B to comparison value of 1
 ldv C, ${label}
-jge B, C     ; A(Memory value) >= B(1), then jump
+jge A, B, C     ; A(Memory value) >= B(1), then jump
 
 `;

src/constants.js

@@ -10,7 +10,7 @@ module.exports = {
     'STA',
     'ATH',
     'CAL',
-    'JLT',
+    'JCP',
     'RET',
     'PSH',
     'POP',
@@ -30,6 +30,22 @@ module.exports = {
   ARITHMETIC_MODE_SHIFT: 12,
   BITWISE_SHIFT_SHIFT: 13,
 
+  JUMP: {
+    EQ: 0,
+    NEQ: 1,
+    LT: 2,
+    GT: 3,
+    LTE: 4,
+    GTE: 5,
+    ZER: 6,
+    NZE: 7,
+
+    R1: 4,
+    R2: 6,
+    AR: 8,
+    OP: 10
+  },
+
   ARITHMETIC: {
     ADD: 0,
     SUB: 1,