implement libc/i48div

src/crt/i48rems.src

@@ -29,12 +29,13 @@ __i48rems:
 	lea	de, iy
 	push	bc
 	pop	hl
-	; negate remainder if dividend was negative
-	call	m, __i48neg
 
 	pop	bc
 	pop	iy
-	ret
+
+	ret	p
+	; negate remainder if dividend was negative
+	jp	__i48neg
 
 	extern	__i48dvrmu
 	extern	__i48neg

src/crt/lldivs.src

@@ -65,11 +65,10 @@ __lldivs:
 	bit	7, (iy + 23)
 .div_quotient_skip:
 
-	call	nz, __llneg
-
 	pop	iy
 
-	ret
+	ret	z
+	jp	__llneg
 
 	extern	__lldvrmu.hijack
 	extern	__llneg

src/libc/i48div.src

@@ -2,7 +2,41 @@
 
 	section	.text
 
-;	public	_i48div
+	public	_i48div
 
 ; i48div_t i48div(int48_t numer, int48_t denom);
-; _i48div:
+_i48div:
+	push	ix
+	ld	ix, 0
+	add	ix, sp
+	ld	c, (ix + 14)
+	ld	b, (ix + 20)
+	ld	a, c
+	xor	a, b
+	ld	a, c
+	push	af
+	rla
+	ld	hl, (ix + 9)
+	ld	de, (ix + 12)
+	call	c, __i48neg
+	ld	a, b
+	rla
+	ld	bc, (ix + 15)
+	ld	iy, (ix + 18)
+	call	c, __uiyubcNeg
+	call	__i48dvrmu
+	ld	ix, (ix + 6)
+	pop	af
+	call	m, __i48neg
+	ld	(ix + 0), hl
+	ld	(ix + 3), de
+	rla
+	call	c, __uiyubcNeg
+	ld	(ix + 6), bc
+	ld	(ix + 9), iy
+	pop	ix
+	ret
+
+	extern	__i48dvrmu
+	extern	__i48neg
+	extern	__uiyubcNeg

test/standalone/i48div/autotest.json

@@ -0,0 +1,40 @@
+{
+  "transfer_files": [
+    "bin/DEMO.8xp"
+  ],
+  "target": {
+    "name": "DEMO",
+    "isASM": true
+  },
+  "sequence": [
+    "action|launch",
+    "delay|1000",
+    "hashWait|1",
+    "key|enter",
+    "delay|300",
+    "hashWait|2"
+  ],
+  "hashes": {
+    "1": {
+      "description": "All tests passed",
+	  "timeout": 5000,
+      "start": "vram_start",
+      "size": "vram_16_size",
+      "expected_CRCs": [
+        "38E2AD5A"
+      ]
+    },
+    "2": {
+      "description": "Exit",
+      "start": "vram_start",
+      "size": "vram_16_size",
+      "expected_CRCs": [
+        "FFAF89BA",
+        "101734A5",
+        "9DA19F44",
+        "A32840C8",
+        "349F4775"
+      ]
+    }
+  }
+}

test/standalone/i48div/makefile

@@ -0,0 +1,19 @@
+# ----------------------------
+# Makefile Options
+# ----------------------------
+
+NAME = DEMO
+ICON = icon.png
+DESCRIPTION = "CE C Toolchain Demo"
+COMPRESSED = NO
+ARCHIVED = NO
+
+CFLAGS = -Wall -Wextra -Wshadow -Wconversion -Wformat=2 -Wno-sign-conversion -Oz
+CXXFLAGS = -Wall -Wextra -Wshadow -Wconversion -Wformat=2 -Wno-sign-conversion -Oz
+
+PREFER_OS_LIBC = NO
+PREFER_OS_CRT = NO
+
+# ----------------------------
+
+include $(shell cedev-config --makefile)

test/standalone/i48div/src/main.c

@@ -0,0 +1,193 @@
+#include <ti/screen.h>
+#include <ti/getcsc.h>
+#include <sys/util.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <ti/sprintf.h>
+#include <ez80_builtin.h>
+
+//------------------------------------------------------------------------------
+// Config
+//------------------------------------------------------------------------------
+
+#define RANDOM_TEST_COUNT 256
+
+// define to 0 or 1
+#define DEBUG_DIAGNOSTICS 0
+
+#define AUTOTEST_SEED 0x7184CE
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+#define C(expr) if (!(expr)) { return __LINE__; }
+
+#define TEST(test) { ret = test; if (ret != 0) { return ret; }}
+
+#ifndef DEBUG_DIAGNOSTICS
+#error "DEBUG_DIAGNOSTICS needs to be defined to 0 or 1"
+#endif
+
+#if RANDOM_TEST_COUNT < 4
+#error "RANDOM_TEST_COUNT is out of range"
+#endif
+
+#if DEBUG_DIAGNOSTICS
+#define test_printf printf
+#else
+#define test_printf(...)
+#endif
+
+static_assert(RAND_MAX == INT_MAX, "RAND_MAX has changed");
+
+#define rand8() ((int8_t)rand())
+
+#define rand16() ((int16_t)rand())
+
+__attribute__((__unused__)) static int24_t rand24(void) {
+    union {
+        int24_t u24;
+        struct {
+            uint16_t lo16;
+            uint8_t hi8;
+        } part;
+    } split;
+    split.part.lo16 = (uint16_t)rand();
+    split.part.hi8 = (uint8_t)rand();
+    return split.u24;
+}
+
+__attribute__((__unused__)) static int32_t rand32(void) {
+    union {
+        int32_t u32;
+        uint16_t u16[2];
+    } split;
+    split.u16[0] = (uint16_t)rand();
+    split.u16[1] = (uint16_t)rand();
+    return split.u32;
+}
+
+__attribute__((__unused__)) static int48_t rand48(void) {
+    union {
+        int48_t u48;
+        uint16_t u16[3];
+    } split;
+    split.u16[0] = (uint16_t)rand();
+    split.u16[1] = (uint16_t)rand();
+    split.u16[2] = (uint16_t)rand();
+    return split.u48;
+}
+
+__attribute__((__unused__)) static int64_t rand64(void) {
+    union {
+        int64_t u64;
+        uint16_t u16[4];
+    } split;
+    split.u16[0] = (uint16_t)rand();
+    split.u16[1] = (uint16_t)rand();
+    split.u16[2] = (uint16_t)rand();
+    split.u16[3] = (uint16_t)rand();
+    return split.u64;
+}
+
+static bool test_i48div(int48_t x, int48_t y) {
+    if (y == 0) {
+        // division by zero
+        return true;
+    }
+    lldiv_t truth = lldiv((int64_t)x, (int64_t)y);
+    i48div_t guess = i48div(x, y);
+    if (
+        ((uint48_t)truth.quot != (uint48_t)guess.quot) ||
+        ((uint48_t)truth.rem != (uint48_t)guess.rem)
+    ) {
+        test_printf(
+            "XN: %012llX\nYD: %012llX\n"\
+            "GQ: %012llX\nGR: %012llX\n"\
+            "TQ: %012llX\nTR: %012llX\n",
+            (uint64_t)(uint48_t)x         , (uint64_t)(uint48_t)y,
+            (uint64_t)(uint48_t)guess.quot, (uint64_t)(uint48_t)guess.rem,
+            (uint64_t)(uint48_t)truth.quot, (uint64_t)(uint48_t)truth.rem
+        );
+        return false;
+    }
+    return true;
+}
+
+int run_tests(void) {
+    srand(AUTOTEST_SEED);
+
+    C(test_i48div(         0,          1));
+    C(test_i48div(         1,          1));
+    C(test_i48div(        -1,          1));
+    C(test_i48div( INT48_MAX,          1));
+    C(test_i48div(-INT48_MAX,          1));
+    C(test_i48div( INT48_MIN,          1));
+    C(test_i48div(         0,         -1));
+    C(test_i48div(         1,         -1));
+    C(test_i48div(        -1,         -1));
+    C(test_i48div( INT48_MAX,         -1));
+    C(test_i48div(-INT48_MAX,         -1));
+    C(test_i48div( INT48_MIN,         -1));
+    C(test_i48div(         0,  INT48_MAX));
+    C(test_i48div(         1,  INT48_MAX));
+    C(test_i48div(        -1,  INT48_MAX));
+    C(test_i48div(         0, -INT48_MAX));
+    C(test_i48div(         1, -INT48_MAX));
+    C(test_i48div(        -1, -INT48_MAX));
+    C(test_i48div(         0,  INT48_MIN));
+    C(test_i48div(         1,  INT48_MIN));
+    C(test_i48div(        -1,  INT48_MIN));
+    C(test_i48div( INT48_MAX,  INT48_MAX));
+    C(test_i48div( INT48_MAX, -INT48_MAX));
+    C(test_i48div( INT48_MAX,  INT48_MIN));
+    C(test_i48div(-INT48_MAX,  INT48_MAX));
+    C(test_i48div(-INT48_MAX, -INT48_MAX));
+    C(test_i48div(-INT48_MAX,  INT48_MIN));
+    C(test_i48div( INT48_MIN,  INT48_MAX));
+    C(test_i48div( INT48_MIN, -INT48_MAX));
+    C(test_i48div( INT48_MIN,  INT48_MIN));
+
+    for (int i = 0; i < RANDOM_TEST_COUNT; i++) {
+        if (!test_i48div(rand48(), rand48())) {
+            return __LINE__;
+        }
+    }
+
+    for (int i = 0; i < RANDOM_TEST_COUNT; i++) {
+        if (!test_i48div(rand48(), rand24())) {
+            return __LINE__;
+        }
+    }
+
+    for (int i = 0; i < RANDOM_TEST_COUNT; i++) {
+        if (!test_i48div(rand48(), rand8())) {
+            return __LINE__;
+        }
+    }
+
+    return 0;
+}
+
+int main(void) {
+    os_ClrHome();
+    int failed_test = run_tests();
+    if (failed_test != 0) {
+        char buf[sizeof("Failed test L-8388608\n")];
+        boot_sprintf(buf, "Failed test L%d\n", failed_test);
+        fputs(buf, stdout);
+    } else {
+        fputs("All tests passed", stdout);
+    }
+
+    while (!os_GetCSC());
+
+    return 0;
+}