diff --git a/core/fpdfapi/font/cfx_cttgsubtable.cpp b/core/fpdfapi/font/cfx_cttgsubtable.cpp
index cb96bf4..bad7f71 100644
--- a/core/fpdfapi/font/cfx_cttgsubtable.cpp
+++ b/core/fpdfapi/font/cfx_cttgsubtable.cpp
@@ -8,6 +8,7 @@
 
 #include <utility>
 
+#include "core/fxcrt/fx_system.h"
 #include "core/fxcrt/stl_util.h"
 #include "core/fxge/cfx_fontmapper.h"
 
@@ -49,11 +50,12 @@
 CFX_CTTGSUBTable::~CFX_CTTGSUBTable() = default;
 
 bool CFX_CTTGSUBTable::LoadGSUBTable(FT_Bytes gsub) {
-  if ((gsub[0] << 24u | gsub[1] << 16u | gsub[2] << 8u | gsub[3]) != 0x00010000)
+  if (FXSYS_UINT32_GET_MSBFIRST(gsub) != 0x00010000)
     return false;
 
-  return Parse(&gsub[gsub[4] << 8 | gsub[5]], &gsub[gsub[6] << 8 | gsub[7]],
-               &gsub[gsub[8] << 8 | gsub[9]]);
+  return Parse(&gsub[FXSYS_UINT16_GET_MSBFIRST(gsub + 4)],
+               &gsub[FXSYS_UINT16_GET_MSBFIRST(gsub + 6)],
+               &gsub[FXSYS_UINT16_GET_MSBFIRST(gsub + 8)]);
 }
 
 uint32_t CFX_CTTGSUBTable::GetVerticalGlyph(uint32_t glyphnum) const {
diff --git a/core/fpdfapi/parser/cpdf_security_handler.cpp b/core/fpdfapi/parser/cpdf_security_handler.cpp
index 2803f15..b54b707 100644
--- a/core/fpdfapi/parser/cpdf_security_handler.cpp
+++ b/core/fpdfapi/parser/cpdf_security_handler.cpp
@@ -385,7 +385,7 @@
   if (buf[9] != 'a' || buf[10] != 'd' || buf[11] != 'b')
     return false;
 
-  if (FXSYS_DWORD_GET_LSBFIRST(buf) != m_Permissions)
+  if (FXSYS_UINT32_GET_LSBFIRST(buf) != m_Permissions)
     return false;
 
   // Relax this check as there appear to be some non-conforming documents
diff --git a/core/fxcodec/bmp/cfx_bmpdecompressor.cpp b/core/fxcodec/bmp/cfx_bmpdecompressor.cpp
index e2f2fc6..eaa8f67 100644
--- a/core/fxcodec/bmp/cfx_bmpdecompressor.cpp
+++ b/core/fxcodec/bmp/cfx_bmpdecompressor.cpp
@@ -93,11 +93,11 @@
   }
 
   bmp_header.bfType =
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&bmp_header.bfType));
-  bmp_header.bfOffBits = FXSYS_DWORD_GET_LSBFIRST(
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&bmp_header.bfType));
+  bmp_header.bfOffBits = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_header.bfOffBits));
   data_size_ =
-      FXSYS_DWORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&bmp_header.bfSize));
+      FXSYS_UINT32_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&bmp_header.bfSize));
   if (bmp_header.bfType != kBmpSignature)
     return BmpDecoder::Status::kFail;
 
@@ -110,7 +110,7 @@
     return BmpDecoder::Status::kFail;
 
   img_ifh_size_ =
-      FXSYS_DWORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_ifh_size_));
+      FXSYS_UINT32_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_ifh_size_));
   pal_type_ = 0;
   BmpDecoder::Status status = ReadBmpHeaderIfh();
   if (status != BmpDecoder::Status::kSuccess)
@@ -128,11 +128,11 @@
       return BmpDecoder::Status::kContinue;
     }
 
-    width_ = FXSYS_WORD_GET_LSBFIRST(
+    width_ = FXSYS_UINT16_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_core_header.bcWidth));
-    height_ = FXSYS_WORD_GET_LSBFIRST(
+    height_ = FXSYS_UINT16_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_core_header.bcHeight));
-    bit_counts_ = FXSYS_WORD_GET_LSBFIRST(
+    bit_counts_ = FXSYS_UINT16_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_core_header.bcBitCount));
     compress_flag_ = kBmpRgb;
     img_tb_flag_ = false;
@@ -146,19 +146,19 @@
       return BmpDecoder::Status::kContinue;
     }
 
-    width_ = FXSYS_DWORD_GET_LSBFIRST(
+    width_ = FXSYS_UINT32_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biWidth));
-    int32_t signed_height = FXSYS_DWORD_GET_LSBFIRST(
+    int32_t signed_height = FXSYS_UINT32_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biHeight));
-    bit_counts_ = FXSYS_WORD_GET_LSBFIRST(
+    bit_counts_ = FXSYS_UINT16_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biBitCount));
-    compress_flag_ = FXSYS_DWORD_GET_LSBFIRST(
+    compress_flag_ = FXSYS_UINT32_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biCompression));
-    color_used_ = FXSYS_DWORD_GET_LSBFIRST(
+    color_used_ = FXSYS_UINT32_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biClrUsed));
-    dpi_x_ = static_cast<int32_t>(FXSYS_DWORD_GET_LSBFIRST(
+    dpi_x_ = static_cast<int32_t>(FXSYS_UINT32_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biXPelsPerMeter)));
-    dpi_y_ = static_cast<int32_t>(FXSYS_DWORD_GET_LSBFIRST(
+    dpi_y_ = static_cast<int32_t>(FXSYS_UINT32_GET_LSBFIRST(
         reinterpret_cast<uint8_t*>(&bmp_info_header.biYPelsPerMeter)));
     if (!SetHeight(signed_height))
       return BmpDecoder::Status::kFail;
@@ -183,21 +183,21 @@
     return BmpDecoder::Status::kContinue;
 
   uint16_t bi_planes;
-  width_ = FXSYS_DWORD_GET_LSBFIRST(
+  width_ = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biWidth));
-  int32_t signed_height = FXSYS_DWORD_GET_LSBFIRST(
+  int32_t signed_height = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biHeight));
-  bit_counts_ = FXSYS_WORD_GET_LSBFIRST(
+  bit_counts_ = FXSYS_UINT16_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biBitCount));
-  compress_flag_ = FXSYS_DWORD_GET_LSBFIRST(
+  compress_flag_ = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biCompression));
-  color_used_ = FXSYS_DWORD_GET_LSBFIRST(
+  color_used_ = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biClrUsed));
-  bi_planes = FXSYS_WORD_GET_LSBFIRST(
+  bi_planes = FXSYS_UINT16_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biPlanes));
-  dpi_x_ = FXSYS_DWORD_GET_LSBFIRST(
+  dpi_x_ = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biXPelsPerMeter));
-  dpi_y_ = FXSYS_DWORD_GET_LSBFIRST(
+  dpi_y_ = FXSYS_UINT32_GET_LSBFIRST(
       reinterpret_cast<uint8_t*>(&bmp_info_header.biYPelsPerMeter));
   if (!SetHeight(signed_height))
     return BmpDecoder::Status::kFail;
@@ -273,9 +273,10 @@
   if (!ReadData(reinterpret_cast<uint8_t*>(masks), sizeof(masks)))
     return BmpDecoder::Status::kContinue;
 
-  mask_red_ = FXSYS_DWORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&masks[0]));
-  mask_green_ = FXSYS_DWORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&masks[1]));
-  mask_blue_ = FXSYS_DWORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&masks[2]));
+  mask_red_ = FXSYS_UINT32_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&masks[0]));
+  mask_green_ =
+      FXSYS_UINT32_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&masks[1]));
+  mask_blue_ = FXSYS_UINT32_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&masks[2]));
   if (mask_red_ & mask_green_ || mask_red_ & mask_blue_ ||
       mask_green_ & mask_blue_) {
     return BmpDecoder::Status::kFail;
@@ -411,7 +412,7 @@
         green_bits -= 8;
         red_bits -= 8;
         for (uint32_t col = 0; col < width_; ++col) {
-          *buf = FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(buf));
+          *buf = FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(buf));
           out_row_buffer_[idx++] =
               static_cast<uint8_t>((*buf & mask_blue_) << blue_bits);
           out_row_buffer_[idx++] =
diff --git a/core/fxcodec/gif/cfx_gifcontext.cpp b/core/fxcodec/gif/cfx_gifcontext.cpp
index 30e4038..cde9bec 100644
--- a/core/fxcodec/gif/cfx_gifcontext.cpp
+++ b/core/fxcodec/gif/cfx_gifcontext.cpp
@@ -387,9 +387,9 @@
   }
 
   width_ = static_cast<int>(
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&lsd.width)));
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&lsd.width)));
   height_ = static_cast<int>(
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&lsd.height)));
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&lsd.height)));
 
   return GifDecoder::Status::kSuccess;
 }
@@ -431,7 +431,7 @@
             std::make_unique<CFX_GifGraphicControlExtension>();
       graphic_control_extension_->block_size = gif_gce.block_size;
       graphic_control_extension_->gce_flags = gif_gce.gce_flags;
-      graphic_control_extension_->delay_time = FXSYS_WORD_GET_LSBFIRST(
+      graphic_control_extension_->delay_time = FXSYS_UINT16_GET_LSBFIRST(
           reinterpret_cast<uint8_t*>(&gif_gce.delay_time));
       graphic_control_extension_->trans_index = gif_gce.trans_index;
       break;
@@ -461,13 +461,13 @@
 
   auto gif_image = std::make_unique<CFX_GifImage>();
   gif_image->image_info.left =
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.left));
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.left));
   gif_image->image_info.top =
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.top));
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.top));
   gif_image->image_info.width =
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.width));
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.width));
   gif_image->image_info.height =
-      FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.height));
+      FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<uint8_t*>(&img_info.height));
   gif_image->image_info.local_flags = img_info.local_flags;
   if (gif_image->image_info.left + gif_image->image_info.width > width_ ||
       gif_image->image_info.top + gif_image->image_info.height > height_)
diff --git a/core/fxcrt/byteorder_unittest.cpp b/core/fxcrt/byteorder_unittest.cpp
index 7b86acf..1133a8a 100644
--- a/core/fxcrt/byteorder_unittest.cpp
+++ b/core/fxcrt/byteorder_unittest.cpp
@@ -4,25 +4,11 @@
 
 #include "core/fxcrt/byteorder.h"
 
+#include "core/fxcrt/fx_system.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
-// Original code to use as a reference implementation.
-
-#define FXSYS_WORD_GET_LSBFIRST(p)                            \
-  (static_cast<uint16_t>((static_cast<uint16_t>(p[1]) << 8) | \
-                         (static_cast<uint16_t>(p[0]))))
-#define FXSYS_WORD_GET_MSBFIRST(p)                            \
-  (static_cast<uint16_t>((static_cast<uint16_t>(p[0]) << 8) | \
-                         (static_cast<uint16_t>(p[1]))))
-#define FXSYS_DWORD_GET_LSBFIRST(p)                                            \
-  ((static_cast<uint32_t>(p[3]) << 24) | (static_cast<uint32_t>(p[2]) << 16) | \
-   (static_cast<uint32_t>(p[1]) << 8) | (static_cast<uint32_t>(p[0])))
-#define FXSYS_DWORD_GET_MSBFIRST(p)                                            \
-  ((static_cast<uint32_t>(p[0]) << 24) | (static_cast<uint32_t>(p[1]) << 16) | \
-   (static_cast<uint32_t>(p[2]) << 8) | (static_cast<uint32_t>(p[3])))
-
 constexpr uint32_t kTestValues32[] = {
     0x0,      0x1,        0x2,        0x3,        0x4,       0xfe,
     0xff,     0x100,      0x101,      0xffff,     0x10000,   0x123456,
@@ -37,7 +23,7 @@
   for (uint32_t v = 0; v < 0x10000; ++v) {
     const uint16_t v16 = v;
     uint16_t expected =
-        FXSYS_WORD_GET_LSBFIRST(reinterpret_cast<const uint8_t*>(&v16));
+        FXSYS_UINT16_GET_LSBFIRST(reinterpret_cast<const uint8_t*>(&v16));
     EXPECT_EQ(expected, ByteSwapToLE16(v16)) << v;
   }
 }
@@ -45,7 +31,7 @@
 TEST(ByteOrder, ByteSwapToLE32) {
   for (uint32_t v : kTestValues32) {
     uint32_t expected =
-        FXSYS_DWORD_GET_LSBFIRST(reinterpret_cast<const uint8_t*>(&v));
+        FXSYS_UINT32_GET_LSBFIRST(reinterpret_cast<const uint8_t*>(&v));
     EXPECT_EQ(expected, ByteSwapToLE32(v)) << v;
   }
 }
@@ -55,7 +41,7 @@
   for (uint32_t v = 0; v < 0x10000; ++v) {
     const uint16_t v16 = v;
     uint16_t expected =
-        FXSYS_WORD_GET_MSBFIRST(reinterpret_cast<const uint8_t*>(&v16));
+        FXSYS_UINT16_GET_MSBFIRST(reinterpret_cast<const uint8_t*>(&v16));
     EXPECT_EQ(expected, ByteSwapToBE16(v16)) << v;
   }
 }
@@ -63,7 +49,7 @@
 TEST(ByteOrder, ByteSwapToBE32) {
   for (uint32_t v : kTestValues32) {
     uint32_t expected =
-        FXSYS_DWORD_GET_MSBFIRST(reinterpret_cast<const uint8_t*>(&v));
+        FXSYS_UINT32_GET_MSBFIRST(reinterpret_cast<const uint8_t*>(&v));
     EXPECT_EQ(expected, ByteSwapToBE32(v)) << v;
   }
 }
diff --git a/core/fxcrt/fx_system.h b/core/fxcrt/fx_system.h
index c17df4d..29b3c56 100644
--- a/core/fxcrt/fx_system.h
+++ b/core/fxcrt/fx_system.h
@@ -127,18 +127,21 @@
 uint32_t FXSYS_GetLastError();
 #endif  // defined(OS_WIN)
 
-#define FXSYS_WORD_GET_LSBFIRST(p)                            \
-  (static_cast<uint16_t>((static_cast<uint16_t>(p[1]) << 8) | \
-                         (static_cast<uint16_t>(p[0]))))
-#define FXSYS_WORD_GET_MSBFIRST(p)                            \
-  (static_cast<uint16_t>((static_cast<uint16_t>(p[0]) << 8) | \
-                         (static_cast<uint16_t>(p[1]))))
-#define FXSYS_DWORD_GET_LSBFIRST(p)                                            \
-  ((static_cast<uint32_t>(p[3]) << 24) | (static_cast<uint32_t>(p[2]) << 16) | \
-   (static_cast<uint32_t>(p[1]) << 8) | (static_cast<uint32_t>(p[0])))
-#define FXSYS_DWORD_GET_MSBFIRST(p)                                            \
-  ((static_cast<uint32_t>(p[0]) << 24) | (static_cast<uint32_t>(p[1]) << 16) | \
-   (static_cast<uint32_t>(p[2]) << 8) | (static_cast<uint32_t>(p[3])))
+#define FXSYS_UINT16_GET_LSBFIRST(p)                            \
+  (static_cast<uint16_t>((static_cast<uint32_t>((p)[1]) << 8) | \
+                         (static_cast<uint32_t>((p)[0]))))
+#define FXSYS_UINT16_GET_MSBFIRST(p)                            \
+  (static_cast<uint16_t>((static_cast<uint32_t>((p)[0]) << 8) | \
+                         (static_cast<uint32_t>((p)[1]))))
+#define FXSYS_UINT32_GET_LSBFIRST(p)       \
+  ((static_cast<uint32_t>((p)[3]) << 24) | \
+   (static_cast<uint32_t>((p)[2]) << 16) | \
+   (static_cast<uint32_t>((p)[1]) << 8) | (static_cast<uint32_t>((p)[0])))
+#define FXSYS_UINT32_GET_MSBFIRST(p)       \
+  ((static_cast<uint32_t>((p)[0]) << 24) | \
+   (static_cast<uint32_t>((p)[1]) << 16) | \
+   (static_cast<uint32_t>((p)[2]) << 8) | (static_cast<uint32_t>((p)[3])))
+
 int32_t FXSYS_atoi(const char* str);
 uint32_t FXSYS_atoui(const char* str);
 int32_t FXSYS_wtoi(const wchar_t* str);
@@ -147,6 +150,7 @@
 int FXSYS_roundf(float f);
 int FXSYS_round(double d);
 float FXSYS_sqrt2(float a, float b);
+
 #ifdef __cplusplus
 }  // extern C
 #endif  // __cplusplus
diff --git a/core/fxge/win32/cwin32_platform.cpp b/core/fxge/win32/cwin32_platform.cpp
index b609f1f..743133c 100644
--- a/core/fxge/win32/cwin32_platform.cpp
+++ b/core/fxge/win32/cwin32_platform.cpp
@@ -394,7 +394,7 @@
                                         uint32_t table,
                                         pdfium::span<uint8_t> buffer) {
   HFONT hOldFont = (HFONT)::SelectObject(m_hDC, (HFONT)hFont);
-  table = FXSYS_DWORD_GET_MSBFIRST(reinterpret_cast<uint8_t*>(&table));
+  table = FXSYS_UINT32_GET_MSBFIRST(reinterpret_cast<uint8_t*>(&table));
   uint32_t size = ::GetFontData(m_hDC, table, 0, buffer.data(), buffer.size());
   ::SelectObject(m_hDC, hOldFont);
   if (size == GDI_ERROR) {