Simplify FX_GetMirrorChar() code.

Change-Id: I43ec0d4a3b60d51c59ba5a540dfe24803e725089
Reviewed-on: https://pdfium-review.googlesource.com/9170
Reviewed-by: Nicolás Peña <npm@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

1 files changed, 19 insertions, 40 deletions

diff --git a/core/fxcrt/fx_unicode.cpp b/core/fxcrt/fx_unicode.cpp
index fce826dac8..595bb65a63 100644
--- a/core/fxcrt/fx_unicode.cpp
+++ b/core/fxcrt/fx_unicode.cpp
@@ -6,6 +6,21 @@
 
 #include "core/fxcrt/fx_ucd.h"
 
+namespace {
+
+constexpr uint32_t kMirrorBits = 23;
+constexpr uint32_t kMirrorMask = 0x1FFU << kMirrorBits;
+
+wchar_t GetMirrorChar(wchar_t wch, uint32_t dwProps) {
+  uint32_t dwTemp = (dwProps & kMirrorMask);
+  if (dwTemp == kMirrorMask)
+    return wch;
+  size_t idx = dwTemp >> kMirrorBits;
+  return idx < kFXTextLayoutBidiMirrorSize ? kFXTextLayoutBidiMirror[idx] : wch;
+}
+
+}  // namespace
+
 uint32_t FX_GetUnicodeProperties(wchar_t wch) {
   size_t idx = static_cast<size_t>(wch);
   if (idx < kTextLayoutCodePropertiesSize)
@@ -13,48 +28,12 @@ uint32_t FX_GetUnicodeProperties(wchar_t wch) {
   return 0;
 }
 
-wchar_t FX_GetMirrorChar(wchar_t wch, bool bRTL, bool bVertical) {
-  uint32_t dwProps = FX_GetUnicodeProperties(wch);
-  uint32_t dwTemp = (dwProps & 0xFF800000);
-  if (bRTL && dwTemp < 0xFF800000) {
-    size_t idx = dwTemp >> 23;
-    if (idx < kFXTextLayoutBidiMirrorSize) {
-      wch = kFXTextLayoutBidiMirror[idx];
-      dwProps = FX_GetUnicodeProperties(wch);
-    }
-  }
-  if (bVertical) {
-    dwTemp = (dwProps & 0x007E0000);
-    if (dwTemp < 0x007E0000) {
-      size_t idx = dwTemp >> 17;
-      if (idx < kFXTextLayoutVerticalMirrorSize)
-        wch = kFXTextLayoutVerticalMirror[idx];
-    }
-  }
-  return wch;
+wchar_t FX_GetMirrorChar(wchar_t wch) {
+  return GetMirrorChar(wch, FX_GetUnicodeProperties(wch));
 }
 
 #ifdef PDF_ENABLE_XFA
-wchar_t FX_GetMirrorChar(wchar_t wch,
-                         uint32_t dwProps,
-                         bool bRTL,
-                         bool bVertical) {
-  uint32_t dwTemp = (dwProps & 0xFF800000);
-  if (bRTL && dwTemp < 0xFF800000) {
-    size_t idx = dwTemp >> 23;
-    if (idx < kFXTextLayoutBidiMirrorSize) {
-      wch = kFXTextLayoutBidiMirror[idx];
-      dwProps = FX_GetUnicodeProperties(wch);
-    }
-  }
-  if (bVertical) {
-    dwTemp = (dwProps & 0x007E0000);
-    if (dwTemp < 0x007E0000) {
-      size_t idx = dwTemp >> 17;
-      if (idx < kFXTextLayoutVerticalMirrorSize)
-        wch = kFXTextLayoutVerticalMirror[idx];
-    }
-  }
-  return wch;
+wchar_t FX_GetMirrorChar(wchar_t wch, uint32_t dwProps) {
+  return GetMirrorChar(wch, dwProps);
 }
 #endif  // PDF_ENABLE_XFA