ICU-20907 Disable optimization on Windows when building for ARM64 with Visual Studio versions below 16.4.
diff --git a/icu4c/source/common/normalizer2impl.cpp b/icu4c/source/common/normalizer2impl.cpp
index b2dd7ad..cbf6b4d 100644
--- a/icu4c/source/common/normalizer2impl.cpp
+++ b/icu4c/source/common/normalizer2impl.cpp
@@ -2088,6 +2088,13 @@
// minDecompNoCP etc. and smallFCD[] are intended to help with any loss of performance,
// at least for ASCII & CJK.
+// Ticket 20907 - The optimizer in MSVC/Visual Studio versions below 16.4 has trouble with this
+// function on Windows ARM64. As a work-around, we disable optimizations for this function.
+// This work-around could/should be removed once the following versions of Visual Studio are no
+// longer supported: All versions of VS2017, and versions of VS2019 below 16.4.
+#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
+#pragma optimize( "", off )
+#endif
// Gets the FCD value from the regular normalization data.
uint16_t Normalizer2Impl::getFCD16FromNormData(UChar32 c) const {
uint16_t norm16=getNorm16(c);
@@ -2121,6 +2128,9 @@
}
return norm16;
}
+#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
+#pragma optimize( "", on )
+#endif
// Dual functionality:
// buffer!=NULL: normalize
diff --git a/icu4c/source/common/ubidiwrt.cpp b/icu4c/source/common/ubidiwrt.cpp
index aa4d6b5..a69c0a4 100644
--- a/icu4c/source/common/ubidiwrt.cpp
+++ b/icu4c/source/common/ubidiwrt.cpp
@@ -346,6 +346,13 @@
return u_terminateUChars(dest, destSize, destLength, pErrorCode);
}
+// Ticket 20907 - The optimizer in MSVC/Visual Studio versions below 16.4 has trouble with this
+// function on Windows ARM64. As a work-around, we disable optimizations for this function.
+// This work-around could/should be removed once the following versions of Visual Studio are no
+// longer supported: All versions of VS2017, and versions of VS2019 below 16.4.
+#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
+#pragma optimize( "", off )
+#endif
U_CAPI int32_t U_EXPORT2
ubidi_writeReordered(UBiDi *pBiDi,
UChar *dest, int32_t destSize,
@@ -638,3 +645,6 @@
return u_terminateUChars(saveDest, destCapacity, destCapacity-destSize, pErrorCode);
}
+#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
+#pragma optimize( "", on )
+#endif
