From 17b167f1a5bc6da49846624e6fabe4f8c925c76c Mon Sep 17 00:00:00 2001
From: Jacob Lifshay <programmerjake@gmail.com>
Date: Wed, 14 Oct 2020 16:28:21 -0700
Subject: [PATCH] add subfic

---
 src/instr_models.rs | 15 +++++++++++++++
 src/lib.rs          |  5 +++++
 2 files changed, 20 insertions(+)

diff --git a/src/instr_models.rs b/src/instr_models.rs
index cdb3d18..27f6740 100644
--- a/src/instr_models.rs
+++ b/src/instr_models.rs
@@ -121,6 +121,21 @@ pub fn subfo(inputs: InstructionInput) -> InstructionResult {
     })
 }
 
+pub fn subfic(inputs: InstructionInput) -> InstructionResult {
+    let ra = inputs.try_get_ra()? as i64;
+    let immediate = inputs.try_get_immediate_s16()? as i64;
+    let immediate_plus_1 = immediate + 1;
+    let not_ra = !ra;
+    let result = not_ra.wrapping_add(immediate_plus_1) as u64;
+    let ca = (not_ra as u64).overflowing_add(immediate_plus_1 as u64).1;
+    let ca32 = (not_ra as u32).overflowing_add(immediate_plus_1 as u32).1;
+    Ok(InstructionOutput {
+        rt: Some(result),
+        carry: Some(CarryFlags { ca, ca32 }),
+        ..InstructionOutput::default()
+    })
+}
+
 create_instr_variants_ov_cr!(addc, addco, addc_, addco_, i64);
 
 pub fn addco(inputs: InstructionInput) -> InstructionResult {
diff --git a/src/lib.rs b/src/lib.rs
index 5c67b24..e49374e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -360,6 +360,11 @@ instructions! {
         "subfo."
     }
 
+    #[enumerant = SubFIC]
+    fn subfic(Ra, ImmediateS16) -> (Rt, Carry) {
+        "subfic"
+    }
+
     // addc
     #[enumerant = AddC]
     fn addc(Ra, Rb) -> (Rt, Carry) {
-- 
2.30.2