diff --git a/Makefile b/Makefile
index 6c1eb51..0e7d818 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@ ASFLAGS=-g -mabi=ilp32e -march=rv32ec
CFLAGS=$(ASFLAGS)
LD=riscv64-unknown-elf-ld
export JQ?=jaq
-export RV32EMU?=$(HOME)/Source/github.com/sysprog21/rv32emu/build/rv32emu
+export QEMU?=qemu-riscv32
all: calc.elf
@@ -14,12 +14,12 @@ check: tests
hello.elf: hello.o
$(LD) -m elf32lriscv $^ -o $@
-calc.elf: hex.o calc.o
+calc.elf: mem.o hex.o debug.o calc.o
$(LD) -m elf32lriscv -T link.ld $^ -o $@
tests: tests/btohex.elf tests/tohex.elf
-tests/btohex.elf: hex.o tests/btohex.o
+tests/btohex.elf: mem.o hex.o debug.o tests/btohex.o
$(LD) -m elf32lriscv -T link.ld $^ -o $@
tests/tohex.elf: hex.o tests/tohex.o
diff --git a/calc.s b/calc.s
index 22b58df..cff8a62 100644
--- a/calc.s
+++ b/calc.s
@@ -4,59 +4,24 @@
# Provide program starting address to linker
.global _start
-.extern tohex
+.extern regdump
/* newlib system calls */
.set SYSEXIT, 93
.set SYSWRITE, 64
-.section .rodata
-str: .ascii "Hello World!\n"
- .set str_size, .-str
-
-str2: .ascii "regdump\n"
- .set str2_size, .-str2
-
-regnames:
- .ascii "x0", "ra", "sp", "gp", "tp", "t0", "t1", "t2", "s0", "s1", "a0", "a1", "a2", "a3", "a4", "a5"
-
-.section .bss
-buf: .skip 20 # room for 20 byte string
- # x10: ABCDEFGH\n is 14 chars
-
-.section .data
-buflen: .byte 0 # length of buf string
+# .section .rodata
+# .section .bss
.text
_start:
- li t1, 0
- li t2, 5
-
- # dummy test for jal instruction
-.L1:
- jal x0, .L2
-.L2:
- nop
-
-loop:
- beq t1, t2, end
-
- li t0, SYSWRITE # "write" syscall
- li a0, 1 # 1 = standard output (stdout)
- la a1, str # load address of hello string
- li a2, str_size # length of hello string
- ecall # invoke syscall to print the string
- addi t1, t1, 1
- j loop
-
-end:
# do some adding
li a0, 0x80000000 # 0.5
li a1, 1 # 1
li a2, 0x80000000 # 0.5
li a3, 1 # 1
- # jal add64
+ jal add64
#add t1, a0, 0 # copy a0 to t0 as end with overwrite it
jal regdump
@@ -82,110 +47,3 @@ add64:
ret
-# Print values of all registers (in hex)
-# write syscall uses t0, a0, a1, a2
-regdump:
- # save all registers to preserve their state when entering the function
- # except sp, which will be offset by -64
- addi sp, sp, -64 # allocate stack space to stash all registers
- sw x0, 0(sp)
- sw x1, 4(sp)
- sw x2, 8(sp)
- sw x3, 12(sp)
- sw x4, 16(sp)
- sw x5, 20(sp)
- sw x6, 24(sp)
- sw x7, 28(sp)
- sw x8, 32(sp)
- sw x9, 36(sp)
- sw x10, 40(sp)
- sw x11, 44(sp)
- sw x12, 48(sp)
- sw x13, 52(sp)
- sw x14, 56(sp)
- sw x15, 60(sp)
-
- li t0, SYSWRITE # "write" syscall
- li a0, 1 # 1 = standard output (stdout)
- la a1, str2 # load address of hello string
- li a2, str2_size # length of other string
- ecall # invoke syscall to print the string
-
- li s0, 0
- li s1, 16
-
-regdump_loop:
- beq s0, s1, regdump_done
- la a1, regnames # load address of regnames
- slli a2, s0, 1 # a2 = s0 * 2
- add a1, a1, a2 # a1 = a1 + a2
-
- # copy regname to buf
- la a0, buf # load address of buf into a0 as dest
- li a2, 2 # copy 2 bytes
- addi sp, sp, -4 # allocate stack space
- sw ra, 0(sp) # save contents of ra
- jal memcpy
- lw ra, 0(sp) # restore contents of ra
- addi sp, sp, 4 # deallocate stack space
- # append ': '
- li t0, ':
- sb t0, 0(a0)
- li t0, 0x20
- sb t0, 1(a0)
- addi a0, a0, 2 # bump a0 address over ': ' text
- mv a1, a0 # load address of output buffer to a1
- slli a2, s0, 2 # calculate the offset of the register value relative to sp
- add a2, a2, sp # a2 = sp + (s0 * 4)
- lw a0, 0(a2) # load register value to format into a0
- addi sp, sp, -8 # allocate stack space
- sw a1, 4(sp) # save contents of a1
- sw ra, 0(sp) # save contents of ra
- jal tohex
- lw ra, 0(sp) # restore contents of ra
- lw a1, 4(sp) # restore contents of a1 (buffer)
- addi sp, sp, 8 # deallocate stack space
- li t0, '\n # append newline
- sb t0, 8(a1)
-
- # print the register name and value
- li t0, SYSWRITE # "write" syscall
- li a0, 1 # 1 = standard output (stdout)
- la a1, buf
- li a2, 4+8+1 # length of register name string:
- # rr: 12345678\n
- ecall # invoke syscall to print the string
-
- addi s0, s0, 1
- j regdump_loop
-
-regdump_done:
- # TODO: Restore s0 & s1
- addi sp, sp, 64 # deallocate stack space
- ret
-
-
-# memcpy, copy n bytes of memory from src to dest
-# arguments:
-# a0: dest address
-# a1: source address
-# a2: number of bytes to copy
-# temporaries used:
-# t0, t1
-# return:
-# a0: address of dest + n
-# a1: address of src + n
-#
-memcpy:
- li t0, 0
-memcpy_loop:
- # TODO: copy in chunks of 4 bytes if n > 4
- beq t0, a2, memcpy_done
- lbu t1, 0(a1)
- sb t1, 0(a0)
- addi a0, a0, 1
- addi a1, a1, 1
- addi t0, t0, 1
- j memcpy_loop
-memcpy_done:
- ret
diff --git a/debug.s b/debug.s
new file mode 100644
index 0000000..90838e7
--- /dev/null
+++ b/debug.s
@@ -0,0 +1,93 @@
+# Debugging routines
+
+.extern tohex
+.extern memcpy
+
+.global regdump
+
+/* newlib system calls */
+.set SYSWRITE, 64
+
+.section .rodata
+regnames:
+ .ascii "x0", "ra", "sp", "gp", "tp", "t0", "t1", "t2", "s0", "s1", "a0", "a1", "a2", "a3", "a4", "a5"
+
+.section .bss
+buf: .skip 15 # room for 20 byte string
+ # x10: ABCDEFGH\n is 14 chars
+.text
+# Print values of all registers (in hex)
+# write syscall uses t0, a0, a1, a2
+regdump:
+ # save all registers to preserve their state when entering the function
+ # except sp, which will be offset by -64
+ addi sp, sp, -64 # allocate stack space to stash all registers
+ sw x0, 0(sp)
+ sw x1, 4(sp)
+ sw x2, 8(sp)
+ sw x3, 12(sp)
+ sw x4, 16(sp)
+ sw x5, 20(sp)
+ sw x6, 24(sp)
+ sw x7, 28(sp)
+ sw x8, 32(sp)
+ sw x9, 36(sp)
+ sw x10, 40(sp)
+ sw x11, 44(sp)
+ sw x12, 48(sp)
+ sw x13, 52(sp)
+ sw x14, 56(sp)
+ sw x15, 60(sp)
+
+ li s0, 0
+ li s1, 16
+
+regdump_loop:
+ beq s0, s1, regdump_done
+ la a1, regnames # load address of regnames
+ slli a2, s0, 1 # a2 = s0 * 2
+ add a1, a1, a2 # a1 = a1 + a2
+
+ # copy regname to buf
+ la a0, buf # load address of buf into a0 as dest
+ li a2, 2 # copy 2 bytes
+ addi sp, sp, -4 # allocate stack space
+ sw ra, 0(sp) # save contents of ra
+ jal memcpy
+ lw ra, 0(sp) # restore contents of ra
+ addi sp, sp, 4 # deallocate stack space
+ # append ': '
+ li t0, ':
+ sb t0, 0(a0)
+ li t0, 0x20
+ sb t0, 1(a0)
+ addi a0, a0, 2 # bump a0 address over ': ' text
+ mv a1, a0 # load address of output buffer to a1
+ slli a2, s0, 2 # calculate the offset of the register value relative to sp
+ add a2, a2, sp # a2 = sp + (s0 * 4)
+ lw a0, 0(a2) # load register value to format into a0
+ addi sp, sp, -8 # allocate stack space
+ sw a1, 4(sp) # save contents of a1
+ sw ra, 0(sp) # save contents of ra
+ jal tohex
+ lw ra, 0(sp) # restore contents of ra
+ lw a1, 4(sp) # restore contents of a1 (buffer)
+ addi sp, sp, 8 # deallocate stack space
+ li t0, '\n # append newline
+ sb t0, 8(a1)
+
+ # print the register name and value
+ li t0, SYSWRITE # "write" syscall
+ li a0, 1 # 1 = standard output (stdout)
+ la a1, buf
+ li a2, 4+8+1 # length of register name string:
+ # rr: 12345678\n
+ ecall # invoke syscall to print the string
+
+ addi s0, s0, 1
+ j regdump_loop
+
+regdump_done:
+ # TODO: Restore s0 & s1
+ addi sp, sp, 64 # deallocate stack space
+ ret
diff --git a/mem.s b/mem.s
new file mode 100644
index 0000000..445a6b1
--- /dev/null
+++ b/mem.s
@@ -0,0 +1,27 @@
+.global memcpy
+
+.text
+# memcpy, copy n bytes of memory from src to dest
+# arguments:
+# a0: dest address
+# a1: source address
+# a2: number of bytes to copy
+# temporaries used:
+# t0, t1
+# return:
+# a0: address of dest + n
+# a1: address of src + n
+#
+memcpy:
+ li t0, 0
+memcpy_loop:
+ # TODO: copy in chunks of 4 bytes if n > 4
+ beq t0, a2, memcpy_done
+ lbu t1, 0(a1)
+ sb t1, 0(a0)
+ addi a0, a0, 1
+ addi a1, a1, 1
+ addi t0, t0, 1
+ j memcpy_loop
+memcpy_done:
+ ret
diff --git a/tests/btohex.s b/tests/btohex.s
index 22a9adf..8ab320b 100644
--- a/tests/btohex.s
+++ b/tests/btohex.s
@@ -5,6 +5,7 @@
.global _start
.extern btohex
+.extern regdump
/* newlib system calls */
.set SYSEXIT, 93
@@ -13,7 +14,7 @@
_start:
li a0, 0xA5
jal btohex
- mv a1, a0
+ jal regdump
li t0, SYSEXIT # "exit" syscall
la a0, 0 # Use 0 return code
diff --git a/tests/test_hex.sh b/tests/test_hex.sh
index 3340d10..ce47338 100644
--- a/tests/test_hex.sh
+++ b/tests/test_hex.sh
@@ -3,16 +3,14 @@
test_btohex() {
# FIXME: Remove grep when this bug is fixed:
# https://github.com/sysprog21/rv32emu/issues/561
- result=$("${RV32EMU}" -d - -q tests/btohex.elf | grep -v '^[0-9]' | "${JQ}" .x11)
+ result=$("${QEMU}" -B 0x80000000 -s 2k tests/btohex.elf | grep '^a0:')
- # 16693 is 5A in ASCII (reversed from input due to little endian)
- test $? -eq 0 && test "${result}" -eq 13633
+ # 3541 is 5A in ASCII (reversed from input due to little endian)
+ test $? -eq 0 && test "${result}" = "a0: 00003541"
}
test_tohex() {
- # FIXME: Remove grep when this bug is fixed:
- # https://github.com/sysprog21/rv32emu/issues/561
- result=$("${RV32EMU}" -q tests/tohex.elf | grep -v '^[0-9]')
+ result=$("${QEMU}" -B 0x80000000 -s 2k tests/tohex.elf)
test $? -eq 0 && test "${result}" = "CAFEFEED"
}