浮動小数点数の比較を行うRP2350コードを出力

以下の、浮動小数点数の比較を実装した。

code:sample/float_if.ml

let a = 1.23 in

let b = 2.45 in

let rec test1 x y =

(* IfFEq で真の場合 *)

if x = y then

print_int 1

else

print_int 0 in

let rec test2 x y =

(* IfFEq で偽の場合 *)

if x = y then

print_int 0

else

print_int 1 in

let rec test3 x y =

(* IfFLE で真の場合 *)

if x <= y then

print_int 1

else

print_int 0 in

let rec test4 x y =

(* IfFLE で偽の場合 *)

if x <= y then

print_int 0

else

print_int 1 in

let rec test5 x y =

if x = y then 1 else 0

in

test1 a a;

print_newline ();

test2 a b;

print_newline ();

(* QEMUのバグ(?)回避のためのコード *)

if a < b then print_int 1 else print_int 0;

print_newline ();

test3 a b;

print_newline ();

test4 b a;

print_newline ();

print_int (test5 a a);

print_newline ()

以下実装。

code:diff

diff --git a/Makefile b/Makefile

index 727e705..3ad2bdb 100644

--- a/Makefile

+++ b/Makefile

@@ -82,6 +82,8 @@ sample/%.res: sample/%.elf

-m 16M \

-nographic \

-monitor none \

+ -d in_asm \

+ -D logfile.txt \

-kernel $<

.PRECIOUS: test/%.s test/% test/%.res test/%.ans test/%.cmp

diff --git a/RP2350/emit.ml b/RP2350/emit.ml

index 58e9f8f..6ff2c67 100644

--- a/RP2350/emit.ml

+++ b/RP2350/emit.ml

@@ -99,14 +99,14 @@ and g' oc = function (* 各命令のアセンブリ生成 (caml2html: emit_gprim

| NonTail(_), Save(x, y) when List.mem x allfregs && not (S.mem y !stackset) ->

savef y;

- Printf.fprintf oc "\tstfd\t%s, %d(%s)\n" (reg x) (offset y) (reg reg_sp)

| NonTail(_), Save(x, y) -> assert (S.mem y !stackset); ()

(* 復帰の仮想命令の実装 (caml2html: emit_restore) *)

| NonTail(x), Restore(y) when List.mem x allregs ->

| NonTail(x), Restore(y) ->

assert (List.mem x allfregs);

- Printf.fprintf oc "\tlfd\t%s, %d(%s)\n" (reg x) (offset y) (reg reg_sp)

(* 末尾だったら計算結果を第一レジスタにセットしてリターン (caml2html: emit_tailret) *)

| Tail, (Nop | Stw _ | Stfd _ | Comment _ | Save _ as exp) ->

g' oc (NonTail(Id.gentmp Type.Unit), exp);

@@ -142,10 +142,12 @@ and g' oc = function (* 各命令のアセンブリ生成 (caml2html: emit_gprim

Printf.fprintf oc "\tcmp %s, %d\n" (reg x) y;

g'_tail_if oc e1 e2 "bge" "blt"

| Tail, IfFEq(x, y, e1, e2) ->

- Printf.fprintf oc "\tfcmpu\tcr7, %s, %s\n" (reg x) (reg y);

+ Printf.fprintf oc "\tvcmp.f32 %s, %s\n" (reg x) (reg y);

+ Printf.fprintf oc "\tvmrs APSR_nzcv, FPSCR\n";

g'_tail_if oc e1 e2 "beq" "bne"

| Tail, IfFLE(x, y, e1, e2) ->

- Printf.fprintf oc "\tfcmpu\tcr7, %s, %s\n" (reg x) (reg y);

+ Printf.fprintf oc "\tvcmp.f32 %s, %s\n" (reg x) (reg y);

+ Printf.fprintf oc "\tvmrs APSR_nzcv, FPSCR\n";

g'_tail_if oc e1 e2 "ble" "bgt"

| NonTail(z), IfEq(x, V(y), e1, e2) ->

Printf.fprintf oc "\tcmpw\tcr7, %s, %s\n" (reg x) (reg y);

@@ -246,7 +248,7 @@ and g'_args oc x_reg_cl ys zs =

(0, [])

zs in

List.iter

- (fun (z, fr) -> Printf.fprintf oc "\tfmr\t%s, %s\n" (reg fr) (reg z))

+ (fun (z, fr) -> Printf.fprintf oc "\tvmov %s, %s\n" (reg fr) (reg z))

(shuffle reg_fsw zfrs)

let h oc { name = Id.L(x); args = _; fargs = _; body = e; ret = _ } =

@@ -269,7 +271,7 @@ let f oc (Prog(data, fundefs, e)) =

Printf.fprintf oc "\t.syntax unified\n";

Printf.fprintf oc "\t.thumb\n";

Printf.fprintf oc "\t.fpu fpv5-sp-d16\n";

- Printf.fprintf oc "\t.align 2\n";

+ Printf.fprintf oc "\t.align 1\n";

Printf.fprintf oc "\t.globl min_caml_start\n";

List.iter (fun fundef -> h oc fundef) fundefs;

Printf.fprintf oc "min_caml_start: # main entry point\n";

diff --git a/sample/float_if.ml b/sample/float_if.ml

new file mode 100644

index 0000000..0bda31b

--- /dev/null

+++ b/sample/float_if.ml

@@ -0,0 +1,45 @@

+ let a = 1.23 in

+ let b = 2.45 in

+ let rec test1 x y =

+ (* IfFEq で真の場合 *)

+ if x = y then

+ print_int 1

+ else

+ print_int 0 in

+ let rec test2 x y =

+ (* IfFEq で偽の場合 *)

+ if x = y then

+ print_int 0

+ else

+ print_int 1 in

+ let rec test3 x y =

+ (* IfFLE で真の場合 *)

+ if x <= y then

+ print_int 1

+ else

+ print_int 0 in

+ let rec test4 x y =

+ (* IfFLE で偽の場合 *)

+ if x <= y then

+ print_int 0

+ else

+ print_int 1 in

+ let rec test5 x y =

+ if x = y then 1 else 0

+ in

+

+test1 a a;

+print_newline ();

+test2 a b;

+print_newline ();

+

+(* QEMUのバグ(?)回避のためのコード *)

+if a < b then print_int 1 else print_int 0;

+print_newline ();

+

+test3 a b;

+print_newline ();

+test4 b a;

+print_newline ();

+print_int (test5 a a);

+print_newline ()

QEMUのバグなのか、以下のコードを消すとQEMUがバグって終了してしまう。実機では動いているので、当面は様子見。

code:ml

(* QEMUのバグ(?)回避のためのコード *)

if a < b then print_int 1 else print_int 0;

print_newline ();