disas/libvixl: Update to upstream VIXL 1.12

Update our copy of libvixl to upstream's 1.12 release.
The major benefit from QEMU's point of view is that some instructions
previously disassembled as "unimplemented (System)" are now displayed
as something more useful. It also fixes some warnings about format
strings that newer w64-mingw32 compilers were emitting.

We didn't have any local changes to libvixl so nothing needed
to be forward-ported.

Although this is a large commit (due to upstream renaming most
of the files), only a few of the files changed in this commit
are not just straight copies of upstream libvixl files:
 disas/arm-a64.cc
 disas/libvixl/Makefile.objs
 disas/libvixl/README

Note that this commit introduces some signed-unsigned comparison
warnings on the old mingw compilers. Those compilers have broken
TLS support anyway so have only ever been much use for compile tests;
anybody still using them should add -Wno-sign-compare to their
--extra-cflags.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 142 insertions, 0 deletions

diff --git a/disas/libvixl/vixl/utils.cc b/disas/libvixl/vixl/utils.cc
new file mode 100644
index 0000000000..3b8bd75fba
--- /dev/null
+++ b/disas/libvixl/vixl/utils.cc
@@ -0,0 +1,142 @@
+// Copyright 2015, ARM Limited
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+//   * Redistributions of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//   * Redistributions in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//   * Neither the name of ARM Limited nor the names of its contributors may be
+//     used to endorse or promote products derived from this software without
+//     specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "vixl/utils.h"
+#include <stdio.h>
+
+namespace vixl {
+
+uint32_t float_to_rawbits(float value) {
+  uint32_t bits = 0;
+  memcpy(&bits, &value, 4);
+  return bits;
+}
+
+
+uint64_t double_to_rawbits(double value) {
+  uint64_t bits = 0;
+  memcpy(&bits, &value, 8);
+  return bits;
+}
+
+
+float rawbits_to_float(uint32_t bits) {
+  float value = 0.0;
+  memcpy(&value, &bits, 4);
+  return value;
+}
+
+
+double rawbits_to_double(uint64_t bits) {
+  double value = 0.0;
+  memcpy(&value, &bits, 8);
+  return value;
+}
+
+
+uint32_t float_sign(float val) {
+  uint32_t rawbits = float_to_rawbits(val);
+  return unsigned_bitextract_32(31, 31, rawbits);
+}
+
+
+uint32_t float_exp(float val) {
+  uint32_t rawbits = float_to_rawbits(val);
+  return unsigned_bitextract_32(30, 23, rawbits);
+}
+
+
+uint32_t float_mantissa(float val) {
+  uint32_t rawbits = float_to_rawbits(val);
+  return unsigned_bitextract_32(22, 0, rawbits);
+}
+
+
+uint32_t double_sign(double val) {
+  uint64_t rawbits = double_to_rawbits(val);
+  return static_cast<uint32_t>(unsigned_bitextract_64(63, 63, rawbits));
+}
+
+
+uint32_t double_exp(double val) {
+  uint64_t rawbits = double_to_rawbits(val);
+  return static_cast<uint32_t>(unsigned_bitextract_64(62, 52, rawbits));
+}
+
+
+uint64_t double_mantissa(double val) {
+  uint64_t rawbits = double_to_rawbits(val);
+  return unsigned_bitextract_64(51, 0, rawbits);
+}
+
+
+float float_pack(uint32_t sign, uint32_t exp, uint32_t mantissa) {
+  uint32_t bits = (sign << 31) | (exp << 23) | mantissa;
+  return rawbits_to_float(bits);
+}
+
+
+double double_pack(uint64_t sign, uint64_t exp, uint64_t mantissa) {
+  uint64_t bits = (sign << 63) | (exp << 52) | mantissa;
+  return rawbits_to_double(bits);
+}
+
+
+int float16classify(float16 value) {
+  uint16_t exponent_max = (1 << 5) - 1;
+  uint16_t exponent_mask = exponent_max << 10;
+  uint16_t mantissa_mask = (1 << 10) - 1;
+
+  uint16_t exponent = (value & exponent_mask) >> 10;
+  uint16_t mantissa = value & mantissa_mask;
+  if (exponent == 0) {
+    if (mantissa == 0) {
+      return FP_ZERO;
+    }
+    return FP_SUBNORMAL;
+  } else if (exponent == exponent_max) {
+    if (mantissa == 0) {
+      return FP_INFINITE;
+    }
+    return FP_NAN;
+  }
+  return FP_NORMAL;
+}
+
+
+unsigned CountClearHalfWords(uint64_t imm, unsigned reg_size) {
+  VIXL_ASSERT((reg_size % 8) == 0);
+  int count = 0;
+  for (unsigned i = 0; i < (reg_size / 16); i++) {
+    if ((imm & 0xffff) == 0) {
+      count++;
+    }
+    imm >>= 16;
+  }
+  return count;
+}
+
+}  // namespace vixl