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Diffstat (limited to 'js/src/jit/arm64/vixl/Instructions-vixl.cpp')
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1 files changed, 670 insertions, 0 deletions
diff --git a/js/src/jit/arm64/vixl/Instructions-vixl.cpp b/js/src/jit/arm64/vixl/Instructions-vixl.cpp new file mode 100644 index 000000000..25b8e307d --- /dev/null +++ b/js/src/jit/arm64/vixl/Instructions-vixl.cpp @@ -0,0 +1,670 @@ +// 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 "jit/arm64/vixl/Instructions-vixl.h" + +#include "jit/arm64/vixl/Assembler-vixl.h" + +namespace vixl { + + +// Floating-point infinity values. +const float16 kFP16PositiveInfinity = 0x7c00; +const float16 kFP16NegativeInfinity = 0xfc00; +const float kFP32PositiveInfinity = rawbits_to_float(0x7f800000); +const float kFP32NegativeInfinity = rawbits_to_float(0xff800000); +const double kFP64PositiveInfinity = + rawbits_to_double(UINT64_C(0x7ff0000000000000)); +const double kFP64NegativeInfinity = + rawbits_to_double(UINT64_C(0xfff0000000000000)); + + +// The default NaN values (for FPCR.DN=1). +const double kFP64DefaultNaN = rawbits_to_double(UINT64_C(0x7ff8000000000000)); +const float kFP32DefaultNaN = rawbits_to_float(0x7fc00000); +const float16 kFP16DefaultNaN = 0x7e00; + + +static uint64_t RotateRight(uint64_t value, + unsigned int rotate, + unsigned int width) { + VIXL_ASSERT(width <= 64); + rotate &= 63; + return ((value & ((UINT64_C(1) << rotate) - 1)) << + (width - rotate)) | (value >> rotate); +} + + +static uint64_t RepeatBitsAcrossReg(unsigned reg_size, + uint64_t value, + unsigned width) { + VIXL_ASSERT((width == 2) || (width == 4) || (width == 8) || (width == 16) || + (width == 32)); + VIXL_ASSERT((reg_size == kWRegSize) || (reg_size == kXRegSize)); + uint64_t result = value & ((UINT64_C(1) << width) - 1); + for (unsigned i = width; i < reg_size; i *= 2) { + result |= (result << i); + } + return result; +} + + +bool Instruction::IsLoad() const { + if (Mask(LoadStoreAnyFMask) != LoadStoreAnyFixed) { + return false; + } + + if (Mask(LoadStorePairAnyFMask) == LoadStorePairAnyFixed) { + return Mask(LoadStorePairLBit) != 0; + } else { + LoadStoreOp op = static_cast<LoadStoreOp>(Mask(LoadStoreMask)); + switch (op) { + case LDRB_w: + case LDRH_w: + case LDR_w: + case LDR_x: + case LDRSB_w: + case LDRSB_x: + case LDRSH_w: + case LDRSH_x: + case LDRSW_x: + case LDR_b: + case LDR_h: + case LDR_s: + case LDR_d: + case LDR_q: return true; + default: return false; + } + } +} + + +bool Instruction::IsStore() const { + if (Mask(LoadStoreAnyFMask) != LoadStoreAnyFixed) { + return false; + } + + if (Mask(LoadStorePairAnyFMask) == LoadStorePairAnyFixed) { + return Mask(LoadStorePairLBit) == 0; + } else { + LoadStoreOp op = static_cast<LoadStoreOp>(Mask(LoadStoreMask)); + switch (op) { + case STRB_w: + case STRH_w: + case STR_w: + case STR_x: + case STR_b: + case STR_h: + case STR_s: + case STR_d: + case STR_q: return true; + default: return false; + } + } +} + + +// Logical immediates can't encode zero, so a return value of zero is used to +// indicate a failure case. Specifically, where the constraints on imm_s are +// not met. +uint64_t Instruction::ImmLogical() const { + unsigned reg_size = SixtyFourBits() ? kXRegSize : kWRegSize; + int32_t n = BitN(); + int32_t imm_s = ImmSetBits(); + int32_t imm_r = ImmRotate(); + + // An integer is constructed from the n, imm_s and imm_r bits according to + // the following table: + // + // N imms immr size S R + // 1 ssssss rrrrrr 64 UInt(ssssss) UInt(rrrrrr) + // 0 0sssss xrrrrr 32 UInt(sssss) UInt(rrrrr) + // 0 10ssss xxrrrr 16 UInt(ssss) UInt(rrrr) + // 0 110sss xxxrrr 8 UInt(sss) UInt(rrr) + // 0 1110ss xxxxrr 4 UInt(ss) UInt(rr) + // 0 11110s xxxxxr 2 UInt(s) UInt(r) + // (s bits must not be all set) + // + // A pattern is constructed of size bits, where the least significant S+1 + // bits are set. The pattern is rotated right by R, and repeated across a + // 32 or 64-bit value, depending on destination register width. + // + + if (n == 1) { + if (imm_s == 0x3f) { + return 0; + } + uint64_t bits = (UINT64_C(1) << (imm_s + 1)) - 1; + return RotateRight(bits, imm_r, 64); + } else { + if ((imm_s >> 1) == 0x1f) { + return 0; + } + for (int width = 0x20; width >= 0x2; width >>= 1) { + if ((imm_s & width) == 0) { + int mask = width - 1; + if ((imm_s & mask) == mask) { + return 0; + } + uint64_t bits = (UINT64_C(1) << ((imm_s & mask) + 1)) - 1; + return RepeatBitsAcrossReg(reg_size, + RotateRight(bits, imm_r & mask, width), + width); + } + } + } + VIXL_UNREACHABLE(); + return 0; +} + + +uint32_t Instruction::ImmNEONabcdefgh() const { + return ImmNEONabc() << 5 | ImmNEONdefgh(); +} + + +float Instruction::Imm8ToFP32(uint32_t imm8) { + // Imm8: abcdefgh (8 bits) + // Single: aBbb.bbbc.defg.h000.0000.0000.0000.0000 (32 bits) + // where B is b ^ 1 + uint32_t bits = imm8; + uint32_t bit7 = (bits >> 7) & 0x1; + uint32_t bit6 = (bits >> 6) & 0x1; + uint32_t bit5_to_0 = bits & 0x3f; + uint32_t result = (bit7 << 31) | ((32 - bit6) << 25) | (bit5_to_0 << 19); + + return rawbits_to_float(result); +} + + +float Instruction::ImmFP32() const { + return Imm8ToFP32(ImmFP()); +} + + +double Instruction::Imm8ToFP64(uint32_t imm8) { + // Imm8: abcdefgh (8 bits) + // Double: aBbb.bbbb.bbcd.efgh.0000.0000.0000.0000 + // 0000.0000.0000.0000.0000.0000.0000.0000 (64 bits) + // where B is b ^ 1 + uint32_t bits = imm8; + uint64_t bit7 = (bits >> 7) & 0x1; + uint64_t bit6 = (bits >> 6) & 0x1; + uint64_t bit5_to_0 = bits & 0x3f; + uint64_t result = (bit7 << 63) | ((256 - bit6) << 54) | (bit5_to_0 << 48); + + return rawbits_to_double(result); +} + + +double Instruction::ImmFP64() const { + return Imm8ToFP64(ImmFP()); +} + + +float Instruction::ImmNEONFP32() const { + return Imm8ToFP32(ImmNEONabcdefgh()); +} + + +double Instruction::ImmNEONFP64() const { + return Imm8ToFP64(ImmNEONabcdefgh()); +} + + +unsigned CalcLSDataSize(LoadStoreOp op) { + VIXL_ASSERT((LSSize_offset + LSSize_width) == (kInstructionSize * 8)); + unsigned size = static_cast<Instr>(op) >> LSSize_offset; + if ((op & LSVector_mask) != 0) { + // Vector register memory operations encode the access size in the "size" + // and "opc" fields. + if ((size == 0) && ((op & LSOpc_mask) >> LSOpc_offset) >= 2) { + size = kQRegSizeInBytesLog2; + } + } + return size; +} + + +unsigned CalcLSPairDataSize(LoadStorePairOp op) { + VIXL_STATIC_ASSERT(kXRegSizeInBytes == kDRegSizeInBytes); + VIXL_STATIC_ASSERT(kWRegSizeInBytes == kSRegSizeInBytes); + switch (op) { + case STP_q: + case LDP_q: return kQRegSizeInBytesLog2; + case STP_x: + case LDP_x: + case STP_d: + case LDP_d: return kXRegSizeInBytesLog2; + default: return kWRegSizeInBytesLog2; + } +} + + +int Instruction::ImmBranchRangeBitwidth(ImmBranchType branch_type) { + switch (branch_type) { + case UncondBranchType: + return ImmUncondBranch_width; + case CondBranchType: + return ImmCondBranch_width; + case CompareBranchType: + return ImmCmpBranch_width; + case TestBranchType: + return ImmTestBranch_width; + default: + VIXL_UNREACHABLE(); + return 0; + } +} + + +int32_t Instruction::ImmBranchForwardRange(ImmBranchType branch_type) { + int32_t encoded_max = 1 << (ImmBranchRangeBitwidth(branch_type) - 1); + return encoded_max * kInstructionSize; +} + + +bool Instruction::IsValidImmPCOffset(ImmBranchType branch_type, + int64_t offset) { + return is_intn(ImmBranchRangeBitwidth(branch_type), offset); +} + +ImmBranchRangeType Instruction::ImmBranchTypeToRange(ImmBranchType branch_type) +{ + switch (branch_type) { + case UncondBranchType: + return UncondBranchRangeType; + case CondBranchType: + case CompareBranchType: + return CondBranchRangeType; + case TestBranchType: + return TestBranchRangeType; + default: + return UnknownBranchRangeType; + } +} + +int32_t Instruction::ImmBranchMaxForwardOffset(ImmBranchRangeType range_type) +{ + // Branches encode a pc-relative two's complement number of 32-bit + // instructions. Compute the number of bytes corresponding to the largest + // positive number of instructions that can be encoded. + switch(range_type) { + case TestBranchRangeType: + return ((1 << ImmTestBranch_width) - 1) / 2 * kInstructionSize; + case CondBranchRangeType: + return ((1 << ImmCondBranch_width) - 1) / 2 * kInstructionSize; + case UncondBranchRangeType: + return ((1 << ImmUncondBranch_width) - 1) / 2 * kInstructionSize; + default: + VIXL_UNREACHABLE(); + return 0; + } +} + +int32_t Instruction::ImmBranchMinBackwardOffset(ImmBranchRangeType range_type) +{ + switch(range_type) { + case TestBranchRangeType: + return -int32_t(1 << ImmTestBranch_width) / 2 * kInstructionSize; + case CondBranchRangeType: + return -int32_t(1 << ImmCondBranch_width) / 2 * kInstructionSize; + case UncondBranchRangeType: + return -int32_t(1 << ImmUncondBranch_width) / 2 * kInstructionSize; + default: + VIXL_UNREACHABLE(); + return 0; + } +} + +const Instruction* Instruction::ImmPCOffsetTarget() const { + const Instruction * base = this; + ptrdiff_t offset; + if (IsPCRelAddressing()) { + // ADR and ADRP. + offset = ImmPCRel(); + if (Mask(PCRelAddressingMask) == ADRP) { + base = AlignDown(base, kPageSize); + offset *= kPageSize; + } else { + VIXL_ASSERT(Mask(PCRelAddressingMask) == ADR); + } + } else { + // All PC-relative branches. + VIXL_ASSERT(BranchType() != UnknownBranchType); + // Relative branch offsets are instruction-size-aligned. + offset = ImmBranch() << kInstructionSizeLog2; + } + return base + offset; +} + + +int Instruction::ImmBranch() const { + switch (BranchType()) { + case CondBranchType: return ImmCondBranch(); + case UncondBranchType: return ImmUncondBranch(); + case CompareBranchType: return ImmCmpBranch(); + case TestBranchType: return ImmTestBranch(); + default: VIXL_UNREACHABLE(); + } + return 0; +} + + +void Instruction::SetImmPCOffsetTarget(const Instruction* target) { + if (IsPCRelAddressing()) { + SetPCRelImmTarget(target); + } else { + SetBranchImmTarget(target); + } +} + + +void Instruction::SetPCRelImmTarget(const Instruction* target) { + ptrdiff_t imm21; + if ((Mask(PCRelAddressingMask) == ADR)) { + imm21 = target - this; + } else { + VIXL_ASSERT(Mask(PCRelAddressingMask) == ADRP); + uintptr_t this_page = reinterpret_cast<uintptr_t>(this) / kPageSize; + uintptr_t target_page = reinterpret_cast<uintptr_t>(target) / kPageSize; + imm21 = target_page - this_page; + } + Instr imm = Assembler::ImmPCRelAddress(static_cast<int32_t>(imm21)); + + SetInstructionBits(Mask(~ImmPCRel_mask) | imm); +} + + +void Instruction::SetBranchImmTarget(const Instruction* target) { + VIXL_ASSERT(((target - this) & 3) == 0); + Instr branch_imm = 0; + uint32_t imm_mask = 0; + int offset = static_cast<int>((target - this) >> kInstructionSizeLog2); + switch (BranchType()) { + case CondBranchType: { + branch_imm = Assembler::ImmCondBranch(offset); + imm_mask = ImmCondBranch_mask; + break; + } + case UncondBranchType: { + branch_imm = Assembler::ImmUncondBranch(offset); + imm_mask = ImmUncondBranch_mask; + break; + } + case CompareBranchType: { + branch_imm = Assembler::ImmCmpBranch(offset); + imm_mask = ImmCmpBranch_mask; + break; + } + case TestBranchType: { + branch_imm = Assembler::ImmTestBranch(offset); + imm_mask = ImmTestBranch_mask; + break; + } + default: VIXL_UNREACHABLE(); + } + SetInstructionBits(Mask(~imm_mask) | branch_imm); +} + + +void Instruction::SetImmLLiteral(const Instruction* source) { + VIXL_ASSERT(IsWordAligned(source)); + ptrdiff_t offset = (source - this) >> kLiteralEntrySizeLog2; + Instr imm = Assembler::ImmLLiteral(static_cast<int>(offset)); + Instr mask = ImmLLiteral_mask; + + SetInstructionBits(Mask(~mask) | imm); +} + + +VectorFormat VectorFormatHalfWidth(const VectorFormat vform) { + VIXL_ASSERT(vform == kFormat8H || vform == kFormat4S || vform == kFormat2D || + vform == kFormatH || vform == kFormatS || vform == kFormatD); + switch (vform) { + case kFormat8H: return kFormat8B; + case kFormat4S: return kFormat4H; + case kFormat2D: return kFormat2S; + case kFormatH: return kFormatB; + case kFormatS: return kFormatH; + case kFormatD: return kFormatS; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + + +VectorFormat VectorFormatDoubleWidth(const VectorFormat vform) { + VIXL_ASSERT(vform == kFormat8B || vform == kFormat4H || vform == kFormat2S || + vform == kFormatB || vform == kFormatH || vform == kFormatS); + switch (vform) { + case kFormat8B: return kFormat8H; + case kFormat4H: return kFormat4S; + case kFormat2S: return kFormat2D; + case kFormatB: return kFormatH; + case kFormatH: return kFormatS; + case kFormatS: return kFormatD; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + + +VectorFormat VectorFormatFillQ(const VectorFormat vform) { + switch (vform) { + case kFormatB: + case kFormat8B: + case kFormat16B: return kFormat16B; + case kFormatH: + case kFormat4H: + case kFormat8H: return kFormat8H; + case kFormatS: + case kFormat2S: + case kFormat4S: return kFormat4S; + case kFormatD: + case kFormat1D: + case kFormat2D: return kFormat2D; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + +VectorFormat VectorFormatHalfWidthDoubleLanes(const VectorFormat vform) { + switch (vform) { + case kFormat4H: return kFormat8B; + case kFormat8H: return kFormat16B; + case kFormat2S: return kFormat4H; + case kFormat4S: return kFormat8H; + case kFormat1D: return kFormat2S; + case kFormat2D: return kFormat4S; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + +VectorFormat VectorFormatDoubleLanes(const VectorFormat vform) { + VIXL_ASSERT(vform == kFormat8B || vform == kFormat4H || vform == kFormat2S); + switch (vform) { + case kFormat8B: return kFormat16B; + case kFormat4H: return kFormat8H; + case kFormat2S: return kFormat4S; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + + +VectorFormat VectorFormatHalfLanes(const VectorFormat vform) { + VIXL_ASSERT(vform == kFormat16B || vform == kFormat8H || vform == kFormat4S); + switch (vform) { + case kFormat16B: return kFormat8B; + case kFormat8H: return kFormat4H; + case kFormat4S: return kFormat2S; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + + +VectorFormat ScalarFormatFromLaneSize(int laneSize) { + switch (laneSize) { + case 8: return kFormatB; + case 16: return kFormatH; + case 32: return kFormatS; + case 64: return kFormatD; + default: VIXL_UNREACHABLE(); return kFormatUndefined; + } +} + + +unsigned RegisterSizeInBitsFromFormat(VectorFormat vform) { + VIXL_ASSERT(vform != kFormatUndefined); + switch (vform) { + case kFormatB: return kBRegSize; + case kFormatH: return kHRegSize; + case kFormatS: return kSRegSize; + case kFormatD: return kDRegSize; + case kFormat8B: + case kFormat4H: + case kFormat2S: + case kFormat1D: return kDRegSize; + default: return kQRegSize; + } +} + + +unsigned RegisterSizeInBytesFromFormat(VectorFormat vform) { + return RegisterSizeInBitsFromFormat(vform) / 8; +} + + +unsigned LaneSizeInBitsFromFormat(VectorFormat vform) { + VIXL_ASSERT(vform != kFormatUndefined); + switch (vform) { + case kFormatB: + case kFormat8B: + case kFormat16B: return 8; + case kFormatH: + case kFormat4H: + case kFormat8H: return 16; + case kFormatS: + case kFormat2S: + case kFormat4S: return 32; + case kFormatD: + case kFormat1D: + case kFormat2D: return 64; + default: VIXL_UNREACHABLE(); return 0; + } +} + + +int LaneSizeInBytesFromFormat(VectorFormat vform) { + return LaneSizeInBitsFromFormat(vform) / 8; +} + + +int LaneSizeInBytesLog2FromFormat(VectorFormat vform) { + VIXL_ASSERT(vform != kFormatUndefined); + switch (vform) { + case kFormatB: + case kFormat8B: + case kFormat16B: return 0; + case kFormatH: + case kFormat4H: + case kFormat8H: return 1; + case kFormatS: + case kFormat2S: + case kFormat4S: return 2; + case kFormatD: + case kFormat1D: + case kFormat2D: return 3; + default: VIXL_UNREACHABLE(); return 0; + } +} + + +int LaneCountFromFormat(VectorFormat vform) { + VIXL_ASSERT(vform != kFormatUndefined); + switch (vform) { + case kFormat16B: return 16; + case kFormat8B: + case kFormat8H: return 8; + case kFormat4H: + case kFormat4S: return 4; + case kFormat2S: + case kFormat2D: return 2; + case kFormat1D: + case kFormatB: + case kFormatH: + case kFormatS: + case kFormatD: return 1; + default: VIXL_UNREACHABLE(); return 0; + } +} + + +int MaxLaneCountFromFormat(VectorFormat vform) { + VIXL_ASSERT(vform != kFormatUndefined); + switch (vform) { + case kFormatB: + case kFormat8B: + case kFormat16B: return 16; + case kFormatH: + case kFormat4H: + case kFormat8H: return 8; + case kFormatS: + case kFormat2S: + case kFormat4S: return 4; + case kFormatD: + case kFormat1D: + case kFormat2D: return 2; + default: VIXL_UNREACHABLE(); return 0; + } +} + + +// Does 'vform' indicate a vector format or a scalar format? +bool IsVectorFormat(VectorFormat vform) { + VIXL_ASSERT(vform != kFormatUndefined); + switch (vform) { + case kFormatB: + case kFormatH: + case kFormatS: + case kFormatD: return false; + default: return true; + } +} + + +int64_t MaxIntFromFormat(VectorFormat vform) { + return INT64_MAX >> (64 - LaneSizeInBitsFromFormat(vform)); +} + + +int64_t MinIntFromFormat(VectorFormat vform) { + return INT64_MIN >> (64 - LaneSizeInBitsFromFormat(vform)); +} + + +uint64_t MaxUintFromFormat(VectorFormat vform) { + return UINT64_MAX >> (64 - LaneSizeInBitsFromFormat(vform)); +} +} // namespace vixl + |