phase12: match func_80029E88 (707 bodies / 716 regions)

config/regions.tsv

@@ -136,6 +136,7 @@
 0x800297F4	0x800298C0	src/func_800297F4.c
 0x800298C0	0x80029A48	src/func_800298C0.c
 0x80029A48	0x80029C84	src/func_80029A48.c
+0x80029E88	0x80029ED8	src/func_80029E88.c
 0x8002A9D4	0x8002AA18	src/func_8002A9D4.c
 0x8002AC84	0x8002ACBC	src/func_8002AC84.c
 0x8002C6EC	0x8002C728	src/func_8002C6EC.c

src/func_80029E88.c

@@ -0,0 +1,29 @@
+/*
+ * func_80029E88 — 80 bytes at 0x80029E88..0x80029ED8
+ *
+ * Squares the input, applies the signed 4095 bias when the square is negative,
+ * shifts by 12, and passes 4096-minus-that-value to func_800F9204. The result of
+ * that helper is then passed with the original input to func_800F2FC0, whose result
+ * is returned.
+ *
+ * The nested call dataflow is byte-required: the second helper receives the first
+ * helper's return value, not the pre-call shifted value. This removes the extra
+ * live local and produces the target's 24-byte frame with only s0 and ra saved.
+ *
+ * LIMITS: arithmetic meaning and helper behavior are not inferred. The square,
+ * signed bias, 4096 constant, shift, call order, argument values, return, frame,
+ * and epilogue are byte evidence.
+ */
+
+extern int func_800F9204(int);
+extern int func_800F2FC0(int, int);
+
+int func_80029E88(int a0)
+{
+    int x = a0 * a0;
+
+    if (x < 0)
+        x += 4095;
+    x >>= 12;
+    return func_800F2FC0(func_800F9204(4096 - x), a0);
+}