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-rw-r--r--contrib/compiler-rt/lib/builtins/arm/bswapsi2.S39
1 files changed, 39 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/builtins/arm/bswapsi2.S b/contrib/compiler-rt/lib/builtins/arm/bswapsi2.S
new file mode 100644
index 000000000000..59ba8158fd57
--- /dev/null
+++ b/contrib/compiler-rt/lib/builtins/arm/bswapsi2.S
@@ -0,0 +1,39 @@
+//===------- bswapsi2 - Implement bswapsi2 --------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "../assembly.h"
+
+ .syntax unified
+ .text
+#if __ARM_ARCH_ISA_THUMB == 2
+ .thumb
+#endif
+
+//
+// extern uint32_t __bswapsi2(uint32_t);
+//
+// Reverse all the bytes in a 32-bit integer.
+//
+ .p2align 2
+#if __ARM_ARCH_ISA_THUMB == 2
+DEFINE_COMPILERRT_THUMB_FUNCTION(__bswapsi2)
+#else
+DEFINE_COMPILERRT_FUNCTION(__bswapsi2)
+#endif
+#if __ARM_ARCH < 6
+ // before armv6 does not have "rev" instruction
+ eor r1, r0, r0, ror #16
+ bic r1, r1, #0xff0000
+ mov r1, r1, lsr #8
+ eor r0, r1, r0, ror #8
+#else
+ rev r0, r0
+#endif
+ JMP(lr)
+END_COMPILERRT_FUNCTION(__bswapsi2)