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-rw-r--r--3rdparty/asmjit/src/asmjit/core/codewriter.cpp278
1 files changed, 278 insertions, 0 deletions
diff --git a/3rdparty/asmjit/src/asmjit/core/codewriter.cpp b/3rdparty/asmjit/src/asmjit/core/codewriter.cpp
new file mode 100644
index 00000000000..2ee5b38cda5
--- /dev/null
+++ b/3rdparty/asmjit/src/asmjit/core/codewriter.cpp
@@ -0,0 +1,278 @@
+// This file is part of AsmJit project <https://asmjit.com>
+//
+// See asmjit.h or LICENSE.md for license and copyright information
+// SPDX-License-Identifier: Zlib
+
+#include "../core/api-build_p.h"
+#include "../core/codeholder.h"
+#include "../core/codewriter_p.h"
+#include "../arm/armutils.h"
+
+ASMJIT_BEGIN_NAMESPACE
+
+bool CodeWriterUtils::encodeOffset32(uint32_t* dst, int64_t offset64, const OffsetFormat& format) noexcept {
+ uint32_t bitCount = format.immBitCount();
+ uint32_t bitShift = format.immBitShift();
+ uint32_t discardLsb = format.immDiscardLsb();
+
+ // Invalid offset (should not happen).
+ if (!bitCount || bitCount > format.valueSize() * 8u)
+ return false;
+
+ uint32_t value;
+ uint32_t u = 0;
+ bool unsignedLogic = format.type() == OffsetType::kUnsignedOffset;
+
+ // First handle all offsets that use additional field for their sign and the offset is encoded as its
+ // absolute value.
+ if (format.hasSignBit()) {
+ u = uint32_t(offset64 >= 0);
+ if (u == 0)
+ offset64 = -offset64;
+ unsignedLogic = true;
+ }
+
+ // First handle all unsigned offset types.
+ if (unsignedLogic) {
+ if (discardLsb) {
+ ASMJIT_ASSERT(discardLsb <= 32);
+ if ((offset64 & Support::lsbMask<uint32_t>(discardLsb)) != 0)
+ return false;
+ offset64 = int64_t(uint64_t(offset64) >> discardLsb);
+ }
+
+ value = uint32_t(offset64 & Support::lsbMask<uint32_t>(bitCount));
+ if (value != offset64)
+ return false;
+ }
+ else {
+ // The rest of OffsetType options are all signed.
+ if (discardLsb) {
+ ASMJIT_ASSERT(discardLsb <= 32);
+ if ((offset64 & Support::lsbMask<uint32_t>(discardLsb)) != 0)
+ return false;
+ offset64 >>= discardLsb;
+ }
+
+ if (!Support::isInt32(offset64))
+ return false;
+
+ value = uint32_t(int32_t(offset64));
+ if (!Support::isEncodableOffset32(int32_t(value), bitCount))
+ return false;
+ }
+
+ switch (format.type()) {
+ case OffsetType::kSignedOffset:
+ case OffsetType::kUnsignedOffset: {
+ *dst = (value & Support::lsbMask<uint32_t>(bitCount)) << bitShift;
+ return true;
+ }
+
+ // Opcode: {.....|imm:1|..N.N|......|imm:3|....|imm:8}
+ case OffsetType::kThumb32_ADR: {
+ // Sanity checks.
+ if (format.valueSize() != 4 || bitCount != 12 || bitShift != 0)
+ return false;
+
+ uint32_t imm8 = (value & 0x00FFu);
+ uint32_t imm3 = (value & 0x0700u) << (12 - 8);
+ uint32_t imm1 = (value & 0x0800u) << (26 - 11);
+ uint32_t n = u ^ 1u;
+
+ *dst = imm8 | imm3 | imm1 | (n << 21) | (n << 23);
+ return true;
+ }
+
+ // Opcode: {....|.|imm[22]|imm[19:10]|..|ja|.|jb|imm[9:0]|.}
+ case OffsetType::kThumb32_BLX:
+ // The calculation is the same as `B`, but the first LSB bit must be zero, so account for that.
+ value <<= 1;
+ ASMJIT_FALLTHROUGH;
+
+ // Opcode: {....|.|imm[23]|imm[20:11]|..|ja|.|jb|imm[10:0]}
+ case OffsetType::kThumb32_B: {
+ // Sanity checks.
+ if (format.valueSize() != 4)
+ return false;
+
+ uint32_t ia = (value & 0x0007FFu);
+ uint32_t ib = (value & 0x1FF800u) << (16 - 11);
+ uint32_t ic = (value & 0x800000u) << (26 - 23);
+ uint32_t ja = ((~value >> 23) ^ (value >> 22)) & 1u;
+ uint32_t jb = ((~value >> 23) ^ (value >> 21)) & 1u;
+
+ *dst = ia | ib | ic | (ja << 14) | (jb << 11);
+ return true;
+ }
+
+ // Opcode: {....|.|imm[19]|....|imm[16:11]|..|ja|.|jb|imm[10:0]}
+ case OffsetType::kThumb32_BCond: {
+ // Sanity checks.
+ if (format.valueSize() != 4 || bitCount != 20 || bitShift != 0)
+ return false;
+
+ uint32_t ia = (value & 0x0007FFu);
+ uint32_t ib = (value & 0x01F800u) << (16 - 11);
+ uint32_t ic = (value & 0x080000u) << (26 - 19);
+ uint32_t ja = ((~value >> 19) ^ (value >> 22)) & 1u;
+ uint32_t jb = ((~value >> 19) ^ (value >> 21)) & 1u;
+
+ *dst = ia | ib | ic | (ja << 14) | (jb << 11);
+ return true;
+ }
+
+ case OffsetType::kAArch32_ADR: {
+ uint32_t encodedImm;
+ if (!arm::Utils::encodeAArch32Imm(value, &encodedImm))
+ return false;
+
+ *dst = (Support::bitMask(22) << u) | (encodedImm << bitShift);
+ return true;
+ }
+
+ case OffsetType::kAArch32_U23_SignedOffset: {
+ *dst = (value << bitShift) | (u << 23);
+ return true;
+ }
+
+ case OffsetType::kAArch32_U23_0To3At0_4To7At8: {
+ // Sanity checks.
+ if (format.valueSize() != 4 || bitCount != 8 || bitShift != 0)
+ return false;
+
+ uint32_t immLo = (value & 0x0Fu);
+ uint32_t immHi = (value & 0xF0u) << (8 - 4);
+
+ *dst = immLo | immHi | (u << 23);
+ return true;
+ }
+
+ case OffsetType::kAArch32_1To24At0_0At24: {
+ // Sanity checks.
+ if (format.valueSize() != 4 || bitCount != 25 || bitShift != 0)
+ return false;
+
+ uint32_t immLo = (value & 0x0000001u) << 24;
+ uint32_t immHi = (value & 0x1FFFFFEu) >> 1;
+
+ *dst = immLo | immHi;
+ return true;
+ }
+
+ case OffsetType::kAArch64_ADR:
+ case OffsetType::kAArch64_ADRP: {
+ // Sanity checks.
+ if (format.valueSize() != 4 || bitCount != 21 || bitShift != 5)
+ return false;
+
+ uint32_t immLo = value & 0x3u;
+ uint32_t immHi = (value >> 2) & Support::lsbMask<uint32_t>(19);
+
+ *dst = (immLo << 29) | (immHi << 5);
+ return true;
+ }
+
+ default:
+ return false;
+ }
+}
+
+bool CodeWriterUtils::encodeOffset64(uint64_t* dst, int64_t offset64, const OffsetFormat& format) noexcept {
+ uint32_t bitCount = format.immBitCount();
+ uint32_t discardLsb = format.immDiscardLsb();
+
+ if (!bitCount || bitCount > format.valueSize() * 8u)
+ return false;
+
+ uint64_t value;
+
+ // First handle all unsigned offset types.
+ if (format.type() == OffsetType::kUnsignedOffset) {
+ if (discardLsb) {
+ ASMJIT_ASSERT(discardLsb <= 32);
+ if ((offset64 & Support::lsbMask<uint32_t>(discardLsb)) != 0)
+ return false;
+ offset64 = int64_t(uint64_t(offset64) >> discardLsb);
+ }
+
+ value = uint64_t(offset64) & Support::lsbMask<uint64_t>(bitCount);
+ if (value != uint64_t(offset64))
+ return false;
+ }
+ else {
+ // The rest of OffsetType options are all signed.
+ if (discardLsb) {
+ ASMJIT_ASSERT(discardLsb <= 32);
+ if ((offset64 & Support::lsbMask<uint32_t>(discardLsb)) != 0)
+ return false;
+ offset64 >>= discardLsb;
+ }
+
+ if (!Support::isEncodableOffset64(offset64, bitCount))
+ return false;
+
+ value = uint64_t(offset64);
+ }
+
+ switch (format.type()) {
+ case OffsetType::kSignedOffset:
+ case OffsetType::kUnsignedOffset: {
+ *dst = (value & Support::lsbMask<uint64_t>(bitCount)) << format.immBitShift();
+ return true;
+ }
+
+ default:
+ return false;
+ }
+}
+
+bool CodeWriterUtils::writeOffset(void* dst, int64_t offset64, const OffsetFormat& format) noexcept {
+ // Offset the destination by ValueOffset so the `dst` points to the
+ // patched word instead of the beginning of the patched region.
+ dst = static_cast<char*>(dst) + format.valueOffset();
+
+ switch (format.valueSize()) {
+ case 1: {
+ uint32_t mask;
+ if (!encodeOffset32(&mask, offset64, format))
+ return false;
+
+ Support::writeU8(dst, uint8_t(Support::readU8(dst) | mask));
+ return true;
+ }
+
+ case 2: {
+ uint32_t mask;
+ if (!encodeOffset32(&mask, offset64, format))
+ return false;
+
+ Support::writeU16uLE(dst, uint16_t(Support::readU16uLE(dst) | mask));
+ return true;
+ }
+
+ case 4: {
+ uint32_t mask;
+ if (!encodeOffset32(&mask, offset64, format)) {
+ return false;
+ }
+
+ Support::writeU32uLE(dst, Support::readU32uLE(dst) | mask);
+ return true;
+ }
+
+ case 8: {
+ uint64_t mask;
+ if (!encodeOffset64(&mask, offset64, format))
+ return false;
+
+ Support::writeU64uLE(dst, Support::readU64uLE(dst) | mask);
+ return true;
+ }
+
+ default:
+ return false;
+ }
+}
+
+ASMJIT_END_NAMESPACE