abs_float関数

code:diff

diff --git a/Makefile b/Makefile

index 4a293ff..f793a5b 100644

--- a/Makefile

+++ b/Makefile

@@ -64,7 +64,7 @@ firmware/firmware.hex:

# riscv64-unknown-elf-objcopy -O verilog --verilog-data-width 4 firmware/firmware.elf firmware/firmware.hex

# MinCaml のプログラムをビルド

-FIRMWARE_TARGET = test/mandelbrot

+FIRMWARE_TARGET = test/abs_float

firmware/firmware.hex: Makefile firmware/$(FIRMWARE_TARGET).ml firmware/libmincaml.S firmware/stub.S

firmware/bin/min-caml firmware/${FIRMWARE_TARGET}

riscv64-unknown-elf-gcc -nostdlib -march=rv32if -mabi=ilp32f -Wl,-Tfirmware/custom.ld firmware/stub.S firmware/${FIRMWARE_TARGET}.s firmware/libmincaml.S -o firmware/firmware.elf

diff --git a/firmware/libmincaml.S b/firmware/libmincaml.S

index fb979a9..5ce1086 100644

--- a/firmware/libmincaml.S

+++ b/firmware/libmincaml.S

@@ -450,12 +450,19 @@ min_caml_print_newline:

ret

//---------------------------------------------------------

-// min_caml_abs_float (float -> float)

+// min_caml_abs_float: 絶対値を返す

+// (float -> float)

//---------------------------------------------------------

.text

.globl min_caml_abs_float

min_caml_abs_float:

- // TODO: あとで実装する

+ // t1 = fa0

+ fmv.x.w t1, fa0

+ // 符号ビットに0（正）をセット

+ li t2, 0x7fffffff

+ and t1, t1, t2

+ // fa0 = t1

+ fmv.w.x fa0, t1

ret

//---------------------------------------------------------

diff --git a/firmware/test/abs_float.ml b/firmware/test/abs_float.ml

new file mode 100644

index 0000000..c36606a

--- /dev/null

+++ b/firmware/test/abs_float.ml

@@ -0,0 +1,27 @@

+(* abs_float 0.0 => 0.0 *)

+print_int (int_of_float (abs_float 0.0 *. 1000.0));

+print_newline ();

+(* abs_float 1.0 => 1.0 *)

+print_int (int_of_float (abs_float 1.0 *. 1000.0));

+print_newline ();

+(* abs_float (-1.0) => 1.0 *)

+print_int (int_of_float (abs_float (-1.0) *. 1000.0));

+print_newline ();

+(* abs_float 1.1 => 1.1 *)

+print_int (int_of_float (abs_float 1.1 *. 1000.0));

+print_newline ();

+(* abs_float (-1.1) => 1.1 *)

+print_int (int_of_float (abs_float (-1.1) *. 1000.0));

+print_newline ();

+(* abs_float 1.9 => 1.9 *)

+print_int (int_of_float (abs_float 1.9 *. 1000.0));

+print_newline ();

+(* abs_float (-1.9) => 1.9 *)

+print_int (int_of_float (abs_float (-1.9) *. 1000.0));

+print_newline ();

+(* abs_float 2.1 => 2.1 *)

+print_int (int_of_float (abs_float 2.1 *. 1000.0));

+print_newline ();

+(* abs_float (-2.1) => 2.1 *)

+print_int (int_of_float (abs_float (-2.1) *. 1000.0));

+print_newline ()