4 files changed, 68 insertions, 20 deletions

diff --git a/include/core/Sk64.h b/include/core/Sk64.h
index 009744938f..c12a97c8a1 100644
--- a/include/core/Sk64.h
+++ b/include/core/Sk64.h
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2006 The Android Open Source Project
  *
@@ -6,7 +5,6 @@
  * found in the LICENSE file.
  */
 
-
 #ifndef Sk64_DEFINED
 #define Sk64_DEFINED
 
@@ -28,6 +26,11 @@ public:
     int64_t as64() const { return ((int64_t)fHi << 32) | fLo; }
     int64_t getLongLong() const { return this->as64(); }
 
+    void set64(int64_t value) {
+        fHi = (int32_t)(value >> 32);
+        fLo = (uint32_t)value;
+    }
+
     /** Returns non-zero if the Sk64 can be represented as a signed 32 bit integer
     */
     SkBool is32() const { return fHi == ((int32_t)fLo >> 31); }
diff --git a/include/core/SkBitmap.h b/include/core/SkBitmap.h
index c0e299ab94..2b900bef34 100644
--- a/include/core/SkBitmap.h
+++ b/include/core/SkBitmap.h
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2006 The Android Open Source Project
  *
@@ -6,17 +5,19 @@
  * found in the LICENSE file.
  */
 
-
 #ifndef SkBitmap_DEFINED
 #define SkBitmap_DEFINED
 
-#include "Sk64.h"
 #include "SkColor.h"
 #include "SkColorTable.h"
 #include "SkImageInfo.h"
 #include "SkPoint.h"
 #include "SkRefCnt.h"
 
+#ifdef SK_SUPPORT_LEGACY_SK64
+    #include "Sk64.h"
+#endif
+
 struct SkIRect;
 struct SkRect;
 class SkPaint;
@@ -149,19 +150,37 @@ public:
     */
     size_t getSafeSize() const ;
 
-    /** Return the byte size of the pixels, based on the height and rowBytes.
-        This routine is slightly slower than getSize(), but does not truncate
-        the answer to 32bits.
-    */
+    /**
+     *  Return the full size of the bitmap, in bytes.
+     */
+    int64_t computeSize64() const {
+        return sk_64_mul(fHeight, fRowBytes);
+    }
+
+    /**
+     *  Return the number of bytes from the pointer returned by getPixels()
+     *  to the end of the allocated space in the buffer. This may be smaller
+     *  than computeSize64() if there is any rowbytes padding beyond the width.
+     */
+    int64_t computeSafeSize64() const {
+        return ComputeSafeSize64((Config)fConfig, fWidth, fHeight, fRowBytes);
+    }
+
+#ifdef SK_SUPPORT_LEGACY_SK64
+    SK_ATTR_DEPRECATED("use getSize64()")
     Sk64 getSize64() const {
         Sk64 size;
-        size.setMul(fHeight, fRowBytes);
+        size.set64(this->computeSize64());
         return size;
     }
 
-    /** Same as getSafeSize(), but does not truncate the answer to 32bits.
-    */
-    Sk64 getSafeSize64() const ;
+    SK_ATTR_DEPRECATED("use getSafeSize64()")
+    Sk64 getSafeSize64() const {
+        Sk64 size;
+        size.set64(this->computeSafeSize64());
+        return size;
+    }
+#endif
 
     /** Returns true if this bitmap is marked as immutable, meaning that the
         contents of its pixels will not change for the lifetime of the bitmap.
@@ -217,7 +236,7 @@ public:
         return ComputeBytesPerPixel(c) >> 1;
     }
 
-    static Sk64 ComputeSize64(Config, int width, int height);
+    static int64_t ComputeSize64(Config, int width, int height);
     static size_t ComputeSize(Config, int width, int height);
 
     /**
@@ -678,10 +697,10 @@ private:
 
     /* Internal computations for safe size.
     */
-    static Sk64 ComputeSafeSize64(Config   config,
-                                  uint32_t width,
-                                  uint32_t height,
-                                  size_t   rowBytes);
+    static int64_t ComputeSafeSize64(Config   config,
+                                     uint32_t width,
+                                     uint32_t height,
+                                     size_t   rowBytes);
     static size_t ComputeSafeSize(Config   config,
                                   uint32_t width,
                                   uint32_t height,
diff --git a/include/core/SkMath.h b/include/core/SkMath.h
index affcadaf2c..ba6223ed06 100644
--- a/include/core/SkMath.h
+++ b/include/core/SkMath.h
@@ -35,6 +35,32 @@ int32_t SkSqrtBits(int32_t value, int bitBias);
  */
 #define SkSqrt32(n)         SkSqrtBits(n, 15)
 
+// 64bit -> 32bit utilities
+
+/**
+ *  Return true iff the 64bit value can exactly be represented in signed 32bits
+ */
+static inline bool sk_64_isS32(int64_t value) {
+    return (int32_t)value == value;
+}
+
+/**
+ *  Return the 64bit argument as signed 32bits, asserting in debug that the arg
+ *  exactly fits in signed 32bits. In the release build, no checks are preformed
+ *  and the return value if the arg does not fit is undefined.
+ */
+static inline int32_t sk_64_asS32(int64_t value) {
+    SkASSERT(sk_64_isS32(value));
+    return (int32_t)value;
+}
+
+// Handy util that can be passed two ints, and will automatically promote to
+// 64bits before the multiply, so the caller doesn't have to remember to cast
+// e.g. (int64_t)a * b;
+static inline int64_t sk_64_mul(int64_t a, int64_t b) {
+    return a * b;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 //! Returns the number of leading zero bits (0...32)
diff --git a/include/core/SkTypes.h b/include/core/SkTypes.h
index c30a8a2d66..06c8583a61 100644
--- a/include/core/SkTypes.h
+++ b/include/core/SkTypes.h
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2006 The Android Open Source Project
  *
@@ -6,7 +5,6 @@
  * found in the LICENSE file.
  */
 
-
 #ifndef SkTypes_DEFINED
 #define SkTypes_DEFINED
 
@@ -15,6 +13,8 @@
 #include "SkPostConfig.h"
 #include <stdint.h>
 
+//#define SK_SUPPORT_LEGACY_SK64
+
 /** \file SkTypes.h
 */