Inline Imf::sampleCount; this is an ABI-breaking change.

gcc generates calls to sampleCount via PLT indirection even within libIlmImf.
As such, they are not inlined and must be treated as having arbitrary side
effects (because of ELF symbol interposition.)  Making addressing computations
visible at call sites allows a much wider range of optimizations by the
compiler beyond simply eliminating the function call overhead.

OpenEXR/IlmImf/ImfMisc.cpp

@@ -132,26 +132,6 @@ bytesPerLineTable (const Header &header,
     return maxBytesPerLine;
 }
 
-
-const int&
-sampleCount(const char* base, int xStride, int yStride, int x, int y)
-{
-    const char* ptr = base + y * yStride + x * xStride;
-    int* intPtr = (int*) ptr;
-
-    return *intPtr;
-}
-
-int&
-sampleCount(char* base, int xStride, int yStride, int x, int y)
-{
-    char* ptr = base + y * yStride + x * xStride;
-    int* intPtr = (int*) ptr;
-
-    return *intPtr;
-}
-
-
 size_t
 bytesPerDeepLineTable (const Header &header,
                        int minY, int maxY,

OpenEXR/IlmImf/ImfMisc.h

@@ -95,14 +95,26 @@ size_t	bytesPerLineTable (const Header &header,
 // pointer, xStride and yStride.
 //
 
-IMF_EXPORT
+inline
 int&
-sampleCount(char* base, int xStride, int yStride, int x, int y);
+sampleCount(char* base, int xStride, int yStride, int x, int y)
+{
+    char* ptr = base + y * yStride + x * xStride;
+    int* intPtr = (int*) ptr;
 
+    return *intPtr;
+}
 
-IMF_EXPORT
+
+inline
 const int&
-sampleCount(const char* base, int xStride, int yStride, int x, int y);
+sampleCount(const char* base, int xStride, int yStride, int x, int y)
+{
+    const char* ptr = base + y * yStride + x * xStride;
+    int* intPtr = (int*) ptr;
+
+    return *intPtr;
+}
 
 //
 // Build a table that lists, for each scanline in a DEEP file's