Fix some typos (found by codespell)

[openjpeg.git] / src / lib / openjp2 / opj_intmath.h

diff --git a/src/lib/openjp2/opj_intmath.h b/src/lib/openjp2/opj_intmath.h
index 754b5512ff2cf64640359c21d23259076fab7159..1b0c9d03328379d80ba7f87abfb9739b2edfa2ff 100644 (file)
--- a/src/lib/openjp2/opj_intmath.h
+++ b/src/lib/openjp2/opj_intmath.h
@@ -208,6 +208,16 @@ static INLINE OPJ_INT32 opj_int_floordivpow2(OPJ_INT32 a, OPJ_INT32 b)
 {
     return a >> b;
 }
+
+/**
+Divide an integer by a power of 2 and round downwards
+@return Returns a divided by 2^b
+*/
+static INLINE OPJ_UINT32 opj_uint_floordivpow2(OPJ_UINT32 a, OPJ_UINT32 b)
+{
+    return a >> b;
+}
+
 /**
 Get logarithm of an integer and round downwards
 @return Returns log2(a)
@@ -266,6 +276,44 @@ static INLINE OPJ_INT32 opj_int_fix_mul_t1(OPJ_INT32 a, OPJ_INT32 b)
     return (OPJ_INT32)(temp >> (13 + 11 - T1_NMSEDEC_FRACBITS)) ;
 }
 
+/**
+Addition two signed integers with a wrap-around behaviour.
+Assumes complement-to-two signed integers.
+@param a
+@param b
+@return Returns a + b
+*/
+static INLINE OPJ_INT32 opj_int_add_no_overflow(OPJ_INT32 a, OPJ_INT32 b)
+{
+    void* pa = &a;
+    void* pb = &b;
+    OPJ_UINT32* upa = (OPJ_UINT32*)pa;
+    OPJ_UINT32* upb = (OPJ_UINT32*)pb;
+    OPJ_UINT32 ures = *upa + *upb;
+    void* pures = &ures;
+    OPJ_INT32* ipres = (OPJ_INT32*)pures;
+    return *ipres;
+}
+
+/**
+Subtract two signed integers with a wrap-around behaviour.
+Assumes complement-to-two signed integers.
+@param a
+@param b
+@return Returns a - b
+*/
+static INLINE OPJ_INT32 opj_int_sub_no_overflow(OPJ_INT32 a, OPJ_INT32 b)
+{
+    void* pa = &a;
+    void* pb = &b;
+    OPJ_UINT32* upa = (OPJ_UINT32*)pa;
+    OPJ_UINT32* upb = (OPJ_UINT32*)pb;
+    OPJ_UINT32 ures = *upa - *upb;
+    void* pures = &ures;
+    OPJ_INT32* ipres = (OPJ_INT32*)pures;
+    return *ipres;
+}
+
 /* ----------------------------------------------------------------------- */
 /*@}*/