diff options
author | Steven Le Rouzic <steven.lerouzic@gmail.com> | 2024-05-12 17:02:54 +0200 |
---|---|---|
committer | Steven Le Rouzic <steven.lerouzic@gmail.com> | 2024-05-12 17:02:54 +0200 |
commit | f9541157b62ec44deff0b906757c223ca0220102 (patch) | |
tree | 4a1792e3623247eb5bd0487b836dc9fa76091f6f | |
parent | 8ebaea458322a2df925cf351bf6b4f300567150d (diff) |
Division
-rw-r--r-- | emulator/hart.c | 65 | ||||
-rw-r--r-- | emulator/hart_test.c | 30 |
2 files changed, 93 insertions, 2 deletions
diff --git a/emulator/hart.c b/emulator/hart.c index 101d77f..297148b 100644 --- a/emulator/hart.c +++ b/emulator/hart.c @@ -220,7 +220,7 @@ static void execute_op(Hart* hart, uint32_t instruction) }
else if (bank == 1)
{
- if ((inst.funct3 & 0x8) == 0)
+ if ((inst.funct3 & 0x4) == 0)
{
uint64_t a = hart->regs[inst.rs1];
uint64_t b = hart->regs[inst.rs2];
@@ -241,7 +241,68 @@ static void execute_op(Hart* hart, uint32_t instruction) }
else
{
- assert(!"Unhandled M OP");
+ uint32_t a = hart->regs[inst.rs1];
+ uint32_t b = hart->regs[inst.rs2];
+
+ switch (inst.funct3 & 0x3)
+ {
+ case 0: // DIV
+ {
+ if (b == 0)
+ {
+ hart->regs[inst.rd] = 0xFFFFFFFF;
+ }
+ else if (a == 0x80000000 && b == 0xFFFFFFFF)
+ {
+ hart->regs[inst.rd] = 0x80000000;
+ }
+ else
+ {
+ hart->regs[inst.rd] = (uint32_t)((int32_t)a / (int32_t)b);
+ }
+ break;
+ }
+ case 1: // DIVU
+ {
+ if (b == 0)
+ {
+ hart->regs[inst.rd] = 0xFFFFFFFF;
+ }
+ else
+ {
+ hart->regs[inst.rd] = a / b;
+ }
+ break;
+ }
+ case 2: // REM
+ {
+ if (b == 0)
+ {
+ hart->regs[inst.rd] = a;
+ }
+ else if (a == 0x80000000 && b == 0xFFFFFFFF)
+ {
+ hart->regs[inst.rd] = 0;
+ }
+ else
+ {
+ hart->regs[inst.rd] = (uint32_t)((int32_t)a % (int32_t)b);
+ }
+ break;
+ }
+ case 3: // REMU
+ {
+ if (b == 0)
+ {
+ hart->regs[inst.rd] = a;
+ }
+ else
+ {
+ hart->regs[inst.rd] = a % b;
+ }
+ break;
+ }
+ }
}
}
else
diff --git a/emulator/hart_test.c b/emulator/hart_test.c index 1611804..0dea92a 100644 --- a/emulator/hart_test.c +++ b/emulator/hart_test.c @@ -263,6 +263,36 @@ static void test_m() execute(&hart, 0x022091b3); // mulh x3, x1, x2
assert(hart.regs[3] == 0x00000000);
+
+ hart.regs[1] = (uint32_t)-63;
+ hart.regs[2] = 4;
+
+ execute(&hart, 0x0220c1b3); // div x3, x1, x2
+ assert(hart.regs[3] == (uint32_t)-15);
+
+ execute(&hart, 0x0220d1b3); // divu x3, x1, x2
+ assert(hart.regs[3] == 0x3FFFFFF0);
+
+ execute(&hart, 0x0220e1b3); // rem x3, x1, x2
+ assert(hart.regs[3] == (uint32_t)-3);
+
+ execute(&hart, 0x0220f1b3); // remu x3, x1, x2
+ assert(hart.regs[3] == 1);
+
+ hart.regs[1] = 30;
+ hart.regs[2] = 0;
+
+ execute(&hart, 0x0220c1b3); // div x3, x1, x2
+ assert(hart.regs[3] == 0xFFFFFFFF);
+
+ execute(&hart, 0x0220d1b3); // divu x3, x1, x2
+ assert(hart.regs[3] == 0xFFFFFFFF);
+
+ execute(&hart, 0x0220e1b3); // rem x3, x1, x2
+ assert(hart.regs[3] == 30);
+
+ execute(&hart, 0x0220f1b3); // remu x3, x1, x2
+ assert(hart.regs[3] == 30);
}
int main(int argc, char* argv[])
|