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-rw-r--r--other-licenses/7zstub/src/C/Bra86.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/C/Bra86.c b/other-licenses/7zstub/src/C/Bra86.c
new file mode 100644
index 0000000000..a6463c63ba
--- /dev/null
+++ b/other-licenses/7zstub/src/C/Bra86.c
@@ -0,0 +1,82 @@
+/* Bra86.c -- Converter for x86 code (BCJ)
+2017-04-03 : Igor Pavlov : Public domain */
+
+#include "Precomp.h"
+
+#include "Bra.h"
+
+#define Test86MSByte(b) ((((b) + 1) & 0xFE) == 0)
+
+SizeT x86_Convert(Byte *data, SizeT size, UInt32 ip, UInt32 *state, int encoding)
+{
+ SizeT pos = 0;
+ UInt32 mask = *state & 7;
+ if (size < 5)
+ return 0;
+ size -= 4;
+ ip += 5;
+
+ for (;;)
+ {
+ Byte *p = data + pos;
+ const Byte *limit = data + size;
+ for (; p < limit; p++)
+ if ((*p & 0xFE) == 0xE8)
+ break;
+
+ {
+ SizeT d = (SizeT)(p - data - pos);
+ pos = (SizeT)(p - data);
+ if (p >= limit)
+ {
+ *state = (d > 2 ? 0 : mask >> (unsigned)d);
+ return pos;
+ }
+ if (d > 2)
+ mask = 0;
+ else
+ {
+ mask >>= (unsigned)d;
+ if (mask != 0 && (mask > 4 || mask == 3 || Test86MSByte(p[(size_t)(mask >> 1) + 1])))
+ {
+ mask = (mask >> 1) | 4;
+ pos++;
+ continue;
+ }
+ }
+ }
+
+ if (Test86MSByte(p[4]))
+ {
+ UInt32 v = ((UInt32)p[4] << 24) | ((UInt32)p[3] << 16) | ((UInt32)p[2] << 8) | ((UInt32)p[1]);
+ UInt32 cur = ip + (UInt32)pos;
+ pos += 5;
+ if (encoding)
+ v += cur;
+ else
+ v -= cur;
+ if (mask != 0)
+ {
+ unsigned sh = (mask & 6) << 2;
+ if (Test86MSByte((Byte)(v >> sh)))
+ {
+ v ^= (((UInt32)0x100 << sh) - 1);
+ if (encoding)
+ v += cur;
+ else
+ v -= cur;
+ }
+ mask = 0;
+ }
+ p[1] = (Byte)v;
+ p[2] = (Byte)(v >> 8);
+ p[3] = (Byte)(v >> 16);
+ p[4] = (Byte)(0 - ((v >> 24) & 1));
+ }
+ else
+ {
+ mask = (mask >> 1) | 4;
+ pos++;
+ }
+ }
+}