Encode function instructions

renderdoc/common/common.cpp

@@ -236,18 +236,36 @@ void FreeAlignedBuffer(byte *buf)
 
 uint32_t Log2Floor(uint32_t value)
 {
-  RDCASSERT(value > 0);
+  if(!value)
+    return ~0U;
   return 31 - Bits::CountLeadingZeroes(value);
 }
 
 #if ENABLED(RDOC_X64)
 uint64_t Log2Floor(uint64_t value)
 {
-  RDCASSERT(value > 0);
+  if(!value)
+    return ~0ULL;
   return 63 - Bits::CountLeadingZeroes(value);
 }
 #endif
 
+uint32_t Log2Ceil(uint32_t value)
+{
+  if(!value)
+    return ~0U;
+  return 32 - Bits::CountLeadingZeroes(value - 1);
+}
+
+#if ENABLED(RDOC_X64)
+uint64_t Log2Ceil(uint64_t value)
+{
+  if(!value)
+    return ~0ULL;
+  return 64 - Bits::CountLeadingZeroes(value - 1);
+}
+#endif
+
 // deliberately leak so it doesn't get destroyed before our static RenderDoc destructor needs it
 static rdcstr *logfile = new rdcstr;
 static FileIO::LogFileHandle *logfileHandle = NULL;

renderdoc/common/common.h

@@ -293,8 +293,10 @@ byte *AllocAlignedBuffer(uint64_t size, uint64_t alignment = 64);
 void FreeAlignedBuffer(byte *buf);
 
 uint32_t Log2Floor(uint32_t value);
+uint32_t Log2Ceil(uint32_t value);
 #if ENABLED(RDOC_X64)
 uint64_t Log2Floor(uint64_t value);
+uint64_t Log2Ceil(uint64_t value);
 #endif
 
 // super ugly - on apple size_t is a separate type, so we need a new overload
@@ -307,6 +309,24 @@ inline size_t Log2Floor(size_t value)
   return (size_t)Log2Floor((uint32_t)value);
 #endif
 }
+
+inline size_t Log2Ceil(size_t value)
+{
+#if ENABLED(RDOC_X64)
+  return (size_t)Log2Ceil((uint64_t)value);
+#else
+  return (size_t)Log2Ceil((uint32_t)value);
+#endif
+}
+
+inline size_t Log2(size_t value)
+{
+#if ENABLED(RDOC_X64)
+  return (size_t)Log2((uint64_t)value);
+#else
+  return (size_t)Log2((uint32_t)value);
+#endif
+}
 #endif
 
 /////////////////////////////////////////////////