seminaries/qtmips/call-syscall: examples from lecture call and syscall.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>

seminaries/qtmips/call-syscall/lec10-01-call4-clobber.S

+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE,   0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+	la   $sp, STACK_INIT
+	li   $s0, 0x12345678
+	addi $a0, $0, 2
+	addi $a1, $0, 3
+	addi $a2, $0, 4
+	addi $a3, $0, 5
+	jal  fun
+	nop
+	add  $t0, $v0, $0
+	sw   $t0, SPILED_REG_LED_LINE($0)
+final:
+	break
+	beq  $0, $0, final
+
+// int fun(int g, h, i, j)
+// g→$a0, h→$a1, i→$a2, j→$a3, $v0 – ret. val, $sX – save, $tX – temp, $ra – ret. addr
+// return (g + h) – (i + j)
+fun:
+	add  $t0, $a0, $a1
+	add  $t1, $a2, $a3
+	sub  $s0, $t0, $t1
+	add  $v0, $s0, $0
+	jr   $ra
+	nop
+
+#pragma qtmips focus memory STACK_INIT-4*8

seminaries/qtmips/call-syscall/lec10-02-call4-save.S

+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE,   0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+	la   $sp, STACK_INIT
+	li   $s0, 0x12345678
+	addi $a0, $0, 2
+	addi $a1, $0, 3
+	addi $a2, $0, 4
+	addi $a3, $0, 5
+	jal  fun
+	nop
+	add  $t0, $v0, $0
+	sw   $t0, SPILED_REG_LED_LINE($0)
+final:
+	break
+	beq  $0, $0, final
+
+// int fun(int g, h, i, j)
+// g→$a0, h→$a1, i→$a2, j→$a3, $v0 – ret. val, $sX – save, $tX – temp, $ra – ret. addr
+// return (g + h) – (i + j)
+fun:
+	addi $sp, $sp, -4
+	sw   $s0, 0($sp)	 // Save $s0 on stack
+	add  $t0, $a0, $a1
+	add  $t1, $a2, $a3	 // Procedure body
+	sub  $s0, $t0, $t1
+	add  $v0, $s0, $zero // Result
+	lw   $s0, 0($sp)	 // Restore $s0
+	addi $sp, $sp, 4
+	jr   $ra		 // Return
+	nop
+
+#pragma qtmips focus memory STACK_INIT-4*8

seminaries/qtmips/call-syscall/lec10-03-fact-buggy.S

+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE,   0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+	la   $sp, STACK_INIT
+	addi $a0, $0, 4	// 4! -> 24
+	jal  fact
+	nop
+	add  $s0, $v0, $0
+	sw   $s0, SPILED_REG_LED_LINE($0)
+final:
+	break
+	beq  $0, $0, final
+	nop
+
+fact:
+	addi  $sp, $sp, -4   // adjust stack for 2 items
+	sw    $a0, 0($sp)    // save argument
+	slti  $t0, $a0, 1    // test for n < 1
+	beq   $t0, $zero, L1
+	addi  $v0, $zero, 1  // if so, result is 1
+	addi  $sp, $sp, 4    // pop 2 items from stack
+	jr    $ra            // and return
+	nop
+L1:	addi $a0, $a0, -1    // else decrement n
+	jal   fact           // recursive call
+	nop
+	lw    $a0, 0($sp)    // restore original n
+	addi  $sp, $sp, 4    // pop 2 items from stack
+	mul   $v0, $a0, $v0  // multiply to get result
+	jr    $ra            // and return
+	nop
+
+#pragma qtmips focus memory STACK_INIT-4*8

seminaries/qtmips/call-syscall/lec10-04-fact-ok.S

+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE,   0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+	la   $sp, STACK_INIT
+	addi $a0, $0, 4	// 4! -> 24
+	jal  fact
+	nop
+	add  $s0, $v0, $0
+	sw   $s0, SPILED_REG_LED_LINE($0)
+final:
+	break
+	beq  $0, $0, final
+	nop
+
+fact:
+	addi  $sp, $sp, -8   // adjust stack for 2 items
+	sw    $ra, 4($sp)    // save return address
+	sw    $a0, 0($sp)    // save argument
+	slti  $t0, $a0, 1    // test for n < 1
+	beq   $t0, $zero, L1
+	addi  $v0, $zero, 1  // if so, result is 1
+	addi  $sp, $sp, 8    // pop 2 items from stack
+	jr    $ra            // and return
+	nop
+L1:	addi $a0, $a0, -1    // else decrement n
+	jal   fact           // recursive call
+	nop
+	lw    $a0, 0($sp)    // restore original n
+	lw    $ra, 4($sp)    // and return address
+	addi  $sp, $sp, 8    // pop 2 items from stack
+	mul   $v0, $a0, $v0  // multiply to get result
+	jr    $ra            // and return
+	nop
+
+#pragma qtmips focus memory STACK_INIT-4*8

seminaries/qtmips/call-syscall/lec10-05-call-6args.S

+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show peripherals
+
+.equ SPILED_REG_LED_LINE,   0xffffc104 // 32 bit word mapped as output
+.equ STACK_INIT, 0x01230000 // The bottom of the stack, the stack grows down
+
+.set noreorder
+.text
+
+main:
+	la   $sp, STACK_INIT
+	addi $a0, $0, 4	// 4! -> 24
+	jal  fact
+	nop
+	add  $s0, $v0, $0
+	sw   $s0, SPILED_REG_LED_LINE($0)
+final:
+	break
+	beq  $0, $0, final
+	nop
+
+fact:
+	addi  $sp, $sp, -8   // adjust stack for 2 items
+	sw    $ra, 4($sp)    // save return address
+	sw    $a0, 0($sp)    // save argument
+	slti  $t0, $a0, 1    // test for n < 1
+	beq   $t0, $zero, L1
+	addi  $v0, $zero, 1  // if so, result is 1
+	addi  $sp, $sp, 8    // pop 2 items from stack
+	jr    $ra            // and return
+	nop
+L1:	addi $a0, $a0, -1    // else decrement n
+	jal   fact           // recursive call
+	nop
+	lw    $a0, 0($sp)    // restore original n
+	lw    $ra, 4($sp)    // and return address
+	addi  $sp, $sp, 8    // pop 2 items from stack
+	mul   $v0, $a0, $v0  // multiply to get result
+	jr    $ra            // and return
+	nop
+
+#pragma qtmips focus memory STACK_INIT-4*8

seminaries/qtmips/call-syscall/lec10-06-linus-hello.S

+// The first program run by Linus on MIPS Linux kernel port
+
+
+// select core without pipeline but with delay slot
+
+#pragma qtmips show registers
+#pragma qtmips show memory
+#pragma qtmips show terminal
+
+// #include <asm/unistd.h>
+// #include <asm/asm.h>
+// #include <sys/syscall.h>
+
+.equ O_RDWR,       02
+
+// Linux kernel compatible system calls subset
+
+.equ SYS_exit,     4001	// void exit(int status)
+.equ SYS_read,     4003	// ssize_t read(int fd, void *buf, size_t count)
+.equ SYS_write,    4004	// ssize_t write(int fd, const void *buf, size_t count)
+.equ SYS_close,    4006	// int close(int fd)
+.equ SYS_open,     4005	// int open(const char *pathname, int flags, mode_t mode)
+.equ SYS_brk,      4045	// void * brk(void *addr)
+.equ SYS_truncate, 4092	// int ftruncate(int fd, off_t length)
+.equ SYS_readv,    4145	// ssize_t readv(int fd, const struct iovec *iov, int iovcnt)
+.equ SYS_writev,   4146	// ssize_t writev(int fd, const struct iovec *iov, int iovcnt)
+
+.set    noreorder
+.text
+
+//      LEAF(main)
+//      fd = open("/dev/tty1", O_RDWR, 0);
+        la      $a0, tty
+        li      $a1, O_RDWR
+        li      $a2, 0
+        li      $v0, SYS_open
+        syscall
+        bne     $a3, $0, quit
+        addi    $s0, $v0, 0         // delay slot
+//      write(fd, "hello, world.\n", 14);
+        addi    $a0, $s0, 0
+        la      $a1, hello
+        li      $a2, 14
+        li      $v0, SYS_write
+        syscall
+//      close(fd);
+        addi    $a0, $s0, 0
+        li      $v0, SYS_close
+        syscall
+
+quit:
+        li      $a0, 0
+        li      $v0, SYS_exit
+        syscall
+
+        j       quit
+        nop
+
+//      END(main)
+
+        .data
+tty:    .asciz  "/dev/tty1"
+hello:  .ascii  "Hello, world.\n"