add floating point error CSRHEADmaster

1 files changed, 6 insertions, 2 deletions

diff --git a/src/core.rs b/src/core.rs
index 2746d1b..24c6a8f 100644
--- a/src/core.rs
+++ b/src/core.rs
@@ -388,8 +388,12 @@ pub fn fdiv_s(state: &mut CpuState, rd: usize, rs1: usize, rs2: usize) {
     let b = state.f_registers[rs2];
 
     state.f_registers[rd] = if b == 0.0 {
-        f32::NAN
-        // todo: raise division by zero in csr
+        state.csr[0x001 /*fflags*/] |= 0b100;
+        if a.is_sign_positive() {
+            f32::INFINITY
+        } else {
+            f32::NEG_INFINITY
+        }
     } else {
         a / b
     }