From 27a0dd4865fb24815c8b8c8e64d7e590a9ff2da4 Mon Sep 17 00:00:00 2001
From: Danny Willems <be.danny.willems@gmail.com>
Date: Mon, 23 Dec 2024 16:23:57 +0100
Subject: [PATCH] o1vm/riscv32im: test dividing by zero

---
 .../programs/riscv32im/bin/div_by_zero        | Bin 0 -> 456 bytes
 .../programs/riscv32im/bin/divu_by_zero       | Bin 0 -> 456 bytes
 .../programs/riscv32im/src/div_by_zero.S      |  19 +++++++++++
 .../programs/riscv32im/src/divu_by_zero.S     |  19 +++++++++++
 o1vm/tests/test_riscv_elf.rs                  |  30 ++++++++++++++++++
 5 files changed, 68 insertions(+)
 create mode 100755 o1vm/resources/programs/riscv32im/bin/div_by_zero
 create mode 100755 o1vm/resources/programs/riscv32im/bin/divu_by_zero
 create mode 100644 o1vm/resources/programs/riscv32im/src/div_by_zero.S
 create mode 100644 o1vm/resources/programs/riscv32im/src/divu_by_zero.S

diff --git a/o1vm/resources/programs/riscv32im/bin/div_by_zero b/o1vm/resources/programs/riscv32im/bin/div_by_zero
new file mode 100755
index 0000000000000000000000000000000000000000..57cd40f70db51171753060c0f6f10029cba63f67
GIT binary patch
literal 456
zcma)2F;2rk5L{mfM4|!R2asq|S>(tED4?RG#yT5EoD_p~w~0_19+3~E;0HW`C-DJh
zY;0P_nw{Cz?wxPnZ}0E2ERz97zJ-}0E}?TIN6@8Qh><z`1fR4Y!vM7S_3Yy;*`v?c
zOHNrl6WN=Cu{h-Ot27qHJ!p@ipgn<tb_SgtOv1>`BSH+R+Di5SJB{0G7hJn28rNPG
zo^It@S3EK7LX{%xyRfQXsv3>(O|w}qXuNM;d$W$If)mNpbJD23lw9jKmAtzv_o^|J
w8?E^d|HUa9`D#3++o3{n#R%?*I0w1ME<xaahCQ-2?2wAS5fc<H$Lz1~2VYM+7XSbN

literal 0
HcmV?d00001

diff --git a/o1vm/resources/programs/riscv32im/bin/divu_by_zero b/o1vm/resources/programs/riscv32im/bin/divu_by_zero
new file mode 100755
index 0000000000000000000000000000000000000000..494eedac4bf4a3d25b3ae260d87eaff3468b92d8
GIT binary patch
literal 456
zcma)2F;2rk5L{mfM4|!R2asq|S>(tED4?RG#yT5EoD_p~w~0_19+3~E;0HW~r|<!0
zY;0P_nw{Cz?wxPnZ}0E2ERz97zJ-}0E}?TIN6@8Qh><z`1fR4Y!vM7S_3Yy;*`v?c
zOHNrl6WN=Cu{h-Ot27qHJ!p@ipgn<tb_SgtOv1>`BSH+R+Di5SJB{0G7hJn28rNPG
zo^It@S3EK7LX{%xyRfQXsv3>(O|w}qXuNM;d$W$If)mNpbJD23lw9jKmAtzv_o^|J
w8?E^d|HUa9`D#3++o3{n#R%?*I0w1ME<xaahCQ-2?2wAS5fc<H$Lz1~2Xp^BCjbBd

literal 0
HcmV?d00001

diff --git a/o1vm/resources/programs/riscv32im/src/div_by_zero.S b/o1vm/resources/programs/riscv32im/src/div_by_zero.S
new file mode 100644
index 0000000000..5f8c490924
--- /dev/null
+++ b/o1vm/resources/programs/riscv32im/src/div_by_zero.S
@@ -0,0 +1,19 @@
+.section .text
+.globl _start
+
+_start:
+    # Signed division by zero (div)
+    li t0, 42             # t0 = 42
+    li t1, 0              # t1 = 0
+    div t2, t0, t1        # t2 = t0 / t1 (Expected: division by zero)
+
+    # Custom exit syscall
+    li a0, 0
+    li a1, 0
+    li a2, 0
+    li a3, 0
+    li a4, 0
+    li a5, 0
+    li a6, 0
+    li a7, 42
+    ecall
diff --git a/o1vm/resources/programs/riscv32im/src/divu_by_zero.S b/o1vm/resources/programs/riscv32im/src/divu_by_zero.S
new file mode 100644
index 0000000000..b44ff50479
--- /dev/null
+++ b/o1vm/resources/programs/riscv32im/src/divu_by_zero.S
@@ -0,0 +1,19 @@
+.section .text
+.globl _start
+
+_start:
+    # Unsigned division by zero (div)
+    li t0, 42             # t0 = 42
+    li t1, 0              # t1 = 0
+    divu t2, t0, t1       # t2 = t0 / t1 (Expected: division by zero)
+
+    # Custom exit syscall
+    li a0, 0
+    li a1, 0
+    li a2, 0
+    li a3, 0
+    li a4, 0
+    li a5, 0
+    li a6, 0
+    li a7, 42
+    ecall
diff --git a/o1vm/tests/test_riscv_elf.rs b/o1vm/tests/test_riscv_elf.rs
index be690f54b2..1034ff17b9 100644
--- a/o1vm/tests/test_riscv_elf.rs
+++ b/o1vm/tests/test_riscv_elf.rs
@@ -354,3 +354,33 @@ fn test_slt() {
     assert_eq!(witness.registers[T5], 0);
     assert_eq!(witness.registers[T6], 0);
 }
+
+#[test]
+#[should_panic]
+fn test_div_by_zero() {
+    let curr_dir = std::env::current_dir().unwrap();
+    let path = curr_dir.join(std::path::PathBuf::from(
+        "resources/programs/riscv32im/bin/div_by_zero",
+    ));
+    let state = o1vm::elf_loader::parse_riscv32(&path).unwrap();
+    let mut witness = Env::<Fp>::create(PAGE_SIZE.try_into().unwrap(), state);
+
+    while !witness.halt {
+        witness.step();
+    }
+}
+
+#[test]
+#[should_panic]
+fn test_divu_by_zero() {
+    let curr_dir = std::env::current_dir().unwrap();
+    let path = curr_dir.join(std::path::PathBuf::from(
+        "resources/programs/riscv32im/bin/divu_by_zero",
+    ));
+    let state = o1vm::elf_loader::parse_riscv32(&path).unwrap();
+    let mut witness = Env::<Fp>::create(PAGE_SIZE.try_into().unwrap(), state);
+
+    while !witness.halt {
+        witness.step();
+    }
+}