[PATCH] D37834: [WebAssembly] Use a seperate wasm data segment for each global symbol

[Derek Schuff via Phabricator via llvm-commits]

dschuff added inline comments.


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Comment at: lib/MC/WasmObjectWriter.cpp:99
 
+struct WasmDataSegment {
+  MCSectionWasm *Section;
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Might be worth putting a comment here (or somewhere) mentioning that because wasm binaries have only one real data section (which is allocated/mapped over the whole memory), each segment has to track its "virtual" section/subsection/whatever we want to call it.


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Comment at: lib/MC/WasmObjectWriter.cpp:102
+  uint32_t Offset;
+  SmallVector<char, 0> Data;
+};
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IIRC A SmallVector with size 0 is no better (worse actually) than a std::vector. We could just use std::vector, or I guess if we really do want one segment per LLVM global, then 4 will be the most common size, so we could just use a Smallvector<4>.


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Comment at: lib/MC/WasmObjectWriter.cpp:271
                         const SmallVector<WasmFunction, 4> &Functions);
-  uint64_t
-  writeDataSection(const SmallVector<char, 0> &DataBytes);
+  void writeDataSection(const SmallVector<WasmDataSegment, 4> &Segments);
   void writeNameSection(const SmallVector<WasmFunction, 4> &Functions,
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APIs should just take `SmallVectorImpl` parameters, and then any size SmallVector can be used as an argument.


https://reviews.llvm.org/D37834