[SPIR-V] vfetch: 32_* and 32_*_FLOAT formats

src/xenia/gpu/dxbc_shader_translator_fetch.cc

@@ -99,8 +99,8 @@ void DxbcShaderTranslator::ProcessVertexFetchInstruction(
     DxbcOpAnd(address_dest, fetch_constant_src.SelectFromSwizzled(0),
               DxbcSrc::LU(~uint32_t(3)));
   }
-  // Add the word offset from the instruction, plus the offset of the first
-  // needed word within the element.
+  // Add the word offset from the instruction (signed), plus the offset of the
+  // first needed word within the element.
   uint32_t first_word_index;
   xe::bit_scan_forward(needed_words, &first_word_index);
   int32_t first_word_buffer_offset =