[llvm] r239944 - [Bitcode] Replace hand-coded little endian handling with Endian.h functions.

Benjamin Kramer benny.kra at googlemail.com
Wed Jun 17 13:55:31 PDT 2015


Author: d0k
Date: Wed Jun 17 15:55:30 2015
New Revision: 239944

URL: http://llvm.org/viewvc/llvm-project?rev=239944&view=rev
Log:
[Bitcode] Replace hand-coded little endian handling with Endian.h functions.

No functional change intended.

Modified:
    llvm/trunk/include/llvm/Bitcode/BitstreamWriter.h
    llvm/trunk/include/llvm/Bitcode/ReaderWriter.h
    llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp

Modified: llvm/trunk/include/llvm/Bitcode/BitstreamWriter.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Bitcode/BitstreamWriter.h?rev=239944&r1=239943&r2=239944&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Bitcode/BitstreamWriter.h (original)
+++ llvm/trunk/include/llvm/Bitcode/BitstreamWriter.h Wed Jun 17 15:55:30 2015
@@ -63,10 +63,7 @@ class BitstreamWriter {
   // BackpatchWord - Backpatch a 32-bit word in the output with the specified
   // value.
   void BackpatchWord(unsigned ByteNo, unsigned NewWord) {
-    Out[ByteNo++] = (unsigned char)(NewWord >>  0);
-    Out[ByteNo++] = (unsigned char)(NewWord >>  8);
-    Out[ByteNo++] = (unsigned char)(NewWord >> 16);
-    Out[ByteNo  ] = (unsigned char)(NewWord >> 24);
+    support::endian::write32le(&Out[ByteNo], NewWord);
   }
 
   void WriteByte(unsigned char Value) {
@@ -74,12 +71,9 @@ class BitstreamWriter {
   }
 
   void WriteWord(unsigned Value) {
-    unsigned char Bytes[4] = {
-      (unsigned char)(Value >>  0),
-      (unsigned char)(Value >>  8),
-      (unsigned char)(Value >> 16),
-      (unsigned char)(Value >> 24) };
-    Out.append(&Bytes[0], &Bytes[4]);
+    Value = support::endian::byte_swap<uint32_t, support::little>(Value);
+    Out.append(reinterpret_cast<const char *>(&Value),
+               reinterpret_cast<const char *>(&Value + 1));
   }
 
   unsigned GetBufferOffset() const {

Modified: llvm/trunk/include/llvm/Bitcode/ReaderWriter.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Bitcode/ReaderWriter.h?rev=239944&r1=239943&r2=239944&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Bitcode/ReaderWriter.h (original)
+++ llvm/trunk/include/llvm/Bitcode/ReaderWriter.h Wed Jun 17 15:55:30 2015
@@ -15,6 +15,7 @@
 #define LLVM_BITCODE_READERWRITER_H
 
 #include "llvm/IR/DiagnosticInfo.h"
+#include "llvm/Support/Endian.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include <memory>
@@ -133,14 +134,8 @@ namespace llvm {
     // Must contain the header!
     if (BufEnd-BufPtr < KnownHeaderSize) return true;
 
-    unsigned Offset = ( BufPtr[OffsetField  ]        |
-                       (BufPtr[OffsetField+1] << 8)  |
-                       (BufPtr[OffsetField+2] << 16) |
-                       (BufPtr[OffsetField+3] << 24));
-    unsigned Size   = ( BufPtr[SizeField    ]        |
-                       (BufPtr[SizeField  +1] << 8)  |
-                       (BufPtr[SizeField  +2] << 16) |
-                       (BufPtr[SizeField  +3] << 24));
+    unsigned Offset = support::endian::read32le(&BufPtr[OffsetField]);
+    unsigned Size = support::endian::read32le(&BufPtr[SizeField]);
 
     // Verify that Offset+Size fits in the file.
     if (VerifyBufferSize && Offset+Size > unsigned(BufEnd-BufPtr))

Modified: llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp?rev=239944&r1=239943&r2=239944&view=diff
==============================================================================
--- llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp (original)
+++ llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp Wed Jun 17 15:55:30 2015
@@ -2406,10 +2406,7 @@ enum {
 
 static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
                                uint32_t &Position) {
-  Buffer[Position + 0] = (unsigned char) (Value >>  0);
-  Buffer[Position + 1] = (unsigned char) (Value >>  8);
-  Buffer[Position + 2] = (unsigned char) (Value >> 16);
-  Buffer[Position + 3] = (unsigned char) (Value >> 24);
+  support::endian::write32le(&Buffer[Position], Value);
   Position += 4;
 }
 





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