| /* |
| * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_ASM_ASSEMBLER_HPP |
| #define SHARE_VM_ASM_ASSEMBLER_HPP |
| |
| #include "asm/codeBuffer.hpp" |
| #include "asm/register.hpp" |
| #include "code/oopRecorder.hpp" |
| #include "code/relocInfo.hpp" |
| #include "memory/allocation.hpp" |
| #include "runtime/vm_version.hpp" |
| #include "utilities/debug.hpp" |
| #include "utilities/growableArray.hpp" |
| #include "utilities/top.hpp" |
| |
| // This file contains platform-independent assembler declarations. |
| |
| class MacroAssembler; |
| class AbstractAssembler; |
| class Label; |
| |
| /** |
| * Labels represent destinations for control transfer instructions. Such |
| * instructions can accept a Label as their target argument. A Label is |
| * bound to the current location in the code stream by calling the |
| * MacroAssembler's 'bind' method, which in turn calls the Label's 'bind' |
| * method. A Label may be referenced by an instruction before it's bound |
| * (i.e., 'forward referenced'). 'bind' stores the current code offset |
| * in the Label object. |
| * |
| * If an instruction references a bound Label, the offset field(s) within |
| * the instruction are immediately filled in based on the Label's code |
| * offset. If an instruction references an unbound label, that |
| * instruction is put on a list of instructions that must be patched |
| * (i.e., 'resolved') when the Label is bound. |
| * |
| * 'bind' will call the platform-specific 'patch_instruction' method to |
| * fill in the offset field(s) for each unresolved instruction (if there |
| * are any). 'patch_instruction' lives in one of the |
| * cpu/<arch>/vm/assembler_<arch>* files. |
| * |
| * Instead of using a linked list of unresolved instructions, a Label has |
| * an array of unresolved instruction code offsets. _patch_index |
| * contains the total number of forward references. If the Label's array |
| * overflows (i.e., _patch_index grows larger than the array size), a |
| * GrowableArray is allocated to hold the remaining offsets. (The cache |
| * size is 4 for now, which handles over 99.5% of the cases) |
| * |
| * Labels may only be used within a single CodeSection. If you need |
| * to create references between code sections, use explicit relocations. |
| */ |
| class Label VALUE_OBJ_CLASS_SPEC { |
| private: |
| enum { PatchCacheSize = 4 }; |
| |
| // _loc encodes both the binding state (via its sign) |
| // and the binding locator (via its value) of a label. |
| // |
| // _loc >= 0 bound label, loc() encodes the target (jump) position |
| // _loc == -1 unbound label |
| int _loc; |
| |
| // References to instructions that jump to this unresolved label. |
| // These instructions need to be patched when the label is bound |
| // using the platform-specific patchInstruction() method. |
| // |
| // To avoid having to allocate from the C-heap each time, we provide |
| // a local cache and use the overflow only if we exceed the local cache |
| int _patches[PatchCacheSize]; |
| int _patch_index; |
| GrowableArray<int>* _patch_overflow; |
| |
| Label(const Label&) { ShouldNotReachHere(); } |
| |
| public: |
| |
| /** |
| * After binding, be sure 'patch_instructions' is called later to link |
| */ |
| void bind_loc(int loc) { |
| assert(loc >= 0, "illegal locator"); |
| assert(_loc == -1, "already bound"); |
| _loc = loc; |
| } |
| void bind_loc(int pos, int sect) { bind_loc(CodeBuffer::locator(pos, sect)); } |
| |
| #ifndef PRODUCT |
| // Iterates over all unresolved instructions for printing |
| void print_instructions(MacroAssembler* masm) const; |
| #endif // PRODUCT |
| |
| /** |
| * Returns the position of the the Label in the code buffer |
| * The position is a 'locator', which encodes both offset and section. |
| */ |
| int loc() const { |
| assert(_loc >= 0, "unbound label"); |
| return _loc; |
| } |
| int loc_pos() const { return CodeBuffer::locator_pos(loc()); } |
| int loc_sect() const { return CodeBuffer::locator_sect(loc()); } |
| |
| bool is_bound() const { return _loc >= 0; } |
| bool is_unbound() const { return _loc == -1 && _patch_index > 0; } |
| bool is_unused() const { return _loc == -1 && _patch_index == 0; } |
| |
| /** |
| * Adds a reference to an unresolved displacement instruction to |
| * this unbound label |
| * |
| * @param cb the code buffer being patched |
| * @param branch_loc the locator of the branch instruction in the code buffer |
| */ |
| void add_patch_at(CodeBuffer* cb, int branch_loc); |
| |
| /** |
| * Iterate over the list of patches, resolving the instructions |
| * Call patch_instruction on each 'branch_loc' value |
| */ |
| void patch_instructions(MacroAssembler* masm); |
| |
| void init() { |
| _loc = -1; |
| _patch_index = 0; |
| _patch_overflow = NULL; |
| } |
| |
| Label() { |
| init(); |
| } |
| }; |
| |
| // A union type for code which has to assemble both constant and |
| // non-constant operands, when the distinction cannot be made |
| // statically. |
| class RegisterOrConstant VALUE_OBJ_CLASS_SPEC { |
| private: |
| Register _r; |
| intptr_t _c; |
| |
| public: |
| RegisterOrConstant(): _r(noreg), _c(0) {} |
| RegisterOrConstant(Register r): _r(r), _c(0) {} |
| RegisterOrConstant(intptr_t c): _r(noreg), _c(c) {} |
| |
| Register as_register() const { assert(is_register(),""); return _r; } |
| intptr_t as_constant() const { assert(is_constant(),""); return _c; } |
| |
| Register register_or_noreg() const { return _r; } |
| intptr_t constant_or_zero() const { return _c; } |
| |
| bool is_register() const { return _r != noreg; } |
| bool is_constant() const { return _r == noreg; } |
| }; |
| |
| // The Abstract Assembler: Pure assembler doing NO optimizations on the |
| // instruction level; i.e., what you write is what you get. |
| // The Assembler is generating code into a CodeBuffer. |
| class AbstractAssembler : public ResourceObj { |
| friend class Label; |
| |
| protected: |
| CodeSection* _code_section; // section within the code buffer |
| OopRecorder* _oop_recorder; // support for relocInfo::oop_type |
| |
| public: |
| // Code emission & accessing |
| address addr_at(int pos) const { return code_section()->start() + pos; } |
| |
| protected: |
| // This routine is called with a label is used for an address. |
| // Labels and displacements truck in offsets, but target must return a PC. |
| address target(Label& L) { return code_section()->target(L, pc()); } |
| |
| bool is8bit(int x) const { return -0x80 <= x && x < 0x80; } |
| bool isByte(int x) const { return 0 <= x && x < 0x100; } |
| bool isShiftCount(int x) const { return 0 <= x && x < 32; } |
| |
| // Instruction boundaries (required when emitting relocatable values). |
| class InstructionMark: public StackObj { |
| private: |
| AbstractAssembler* _assm; |
| |
| public: |
| InstructionMark(AbstractAssembler* assm) : _assm(assm) { |
| assert(assm->inst_mark() == NULL, "overlapping instructions"); |
| _assm->set_inst_mark(); |
| } |
| ~InstructionMark() { |
| _assm->clear_inst_mark(); |
| } |
| }; |
| friend class InstructionMark; |
| #ifdef ASSERT |
| // Make it return true on platforms which need to verify |
| // instruction boundaries for some operations. |
| static bool pd_check_instruction_mark(); |
| |
| // Add delta to short branch distance to verify that it still fit into imm8. |
| int _short_branch_delta; |
| |
| int short_branch_delta() const { return _short_branch_delta; } |
| void set_short_branch_delta() { _short_branch_delta = 32; } |
| void clear_short_branch_delta() { _short_branch_delta = 0; } |
| |
| class ShortBranchVerifier: public StackObj { |
| private: |
| AbstractAssembler* _assm; |
| |
| public: |
| ShortBranchVerifier(AbstractAssembler* assm) : _assm(assm) { |
| assert(assm->short_branch_delta() == 0, "overlapping instructions"); |
| _assm->set_short_branch_delta(); |
| } |
| ~ShortBranchVerifier() { |
| _assm->clear_short_branch_delta(); |
| } |
| }; |
| #else |
| // Dummy in product. |
| class ShortBranchVerifier: public StackObj { |
| public: |
| ShortBranchVerifier(AbstractAssembler* assm) {} |
| }; |
| #endif |
| |
| public: |
| |
| // Creation |
| AbstractAssembler(CodeBuffer* code); |
| |
| // ensure buf contains all code (call this before using/copying the code) |
| void flush(); |
| |
| void emit_int8( int8_t x) { code_section()->emit_int8( x); } |
| void emit_int16( int16_t x) { code_section()->emit_int16( x); } |
| void emit_int32( int32_t x) { code_section()->emit_int32( x); } |
| void emit_int64( int64_t x) { code_section()->emit_int64( x); } |
| |
| void emit_float( jfloat x) { code_section()->emit_float( x); } |
| void emit_double( jdouble x) { code_section()->emit_double( x); } |
| void emit_address(address x) { code_section()->emit_address(x); } |
| |
| // min and max values for signed immediate ranges |
| static int min_simm(int nbits) { return -(intptr_t(1) << (nbits - 1)) ; } |
| static int max_simm(int nbits) { return (intptr_t(1) << (nbits - 1)) - 1; } |
| |
| // Define some: |
| static int min_simm10() { return min_simm(10); } |
| static int min_simm13() { return min_simm(13); } |
| static int min_simm16() { return min_simm(16); } |
| |
| // Test if x is within signed immediate range for nbits |
| static bool is_simm(intptr_t x, int nbits) { return min_simm(nbits) <= x && x <= max_simm(nbits); } |
| |
| // Define some: |
| static bool is_simm5( intptr_t x) { return is_simm(x, 5 ); } |
| static bool is_simm8( intptr_t x) { return is_simm(x, 8 ); } |
| static bool is_simm10(intptr_t x) { return is_simm(x, 10); } |
| static bool is_simm11(intptr_t x) { return is_simm(x, 11); } |
| static bool is_simm12(intptr_t x) { return is_simm(x, 12); } |
| static bool is_simm13(intptr_t x) { return is_simm(x, 13); } |
| static bool is_simm16(intptr_t x) { return is_simm(x, 16); } |
| static bool is_simm26(intptr_t x) { return is_simm(x, 26); } |
| static bool is_simm32(intptr_t x) { return is_simm(x, 32); } |
| |
| // Accessors |
| CodeSection* code_section() const { return _code_section; } |
| CodeBuffer* code() const { return code_section()->outer(); } |
| int sect() const { return code_section()->index(); } |
| address pc() const { return code_section()->end(); } |
| int offset() const { return code_section()->size(); } |
| int locator() const { return CodeBuffer::locator(offset(), sect()); } |
| |
| OopRecorder* oop_recorder() const { return _oop_recorder; } |
| void set_oop_recorder(OopRecorder* r) { _oop_recorder = r; } |
| |
| address inst_mark() const { return code_section()->mark(); } |
| void set_inst_mark() { code_section()->set_mark(); } |
| void clear_inst_mark() { code_section()->clear_mark(); } |
| |
| // Constants in code |
| void relocate(RelocationHolder const& rspec, int format = 0) { |
| assert(!pd_check_instruction_mark() |
| || inst_mark() == NULL || inst_mark() == code_section()->end(), |
| "call relocate() between instructions"); |
| code_section()->relocate(code_section()->end(), rspec, format); |
| } |
| void relocate( relocInfo::relocType rtype, int format = 0) { |
| code_section()->relocate(code_section()->end(), rtype, format); |
| } |
| |
| static int code_fill_byte(); // used to pad out odd-sized code buffers |
| |
| // Associate a comment with the current offset. It will be printed |
| // along with the disassembly when printing nmethods. Currently |
| // only supported in the instruction section of the code buffer. |
| void block_comment(const char* comment); |
| // Copy str to a buffer that has the same lifetime as the CodeBuffer |
| const char* code_string(const char* str); |
| |
| // Label functions |
| void bind(Label& L); // binds an unbound label L to the current code position |
| |
| // Move to a different section in the same code buffer. |
| void set_code_section(CodeSection* cs); |
| |
| // Inform assembler when generating stub code and relocation info |
| address start_a_stub(int required_space); |
| void end_a_stub(); |
| // Ditto for constants. |
| address start_a_const(int required_space, int required_align = sizeof(double)); |
| void end_a_const(CodeSection* cs); // Pass the codesection to continue in (insts or stubs?). |
| |
| // constants support |
| // |
| // We must remember the code section (insts or stubs) in c1 |
| // so we can reset to the proper section in end_a_const(). |
| address long_constant(jlong c) { |
| CodeSection* c1 = _code_section; |
| address ptr = start_a_const(sizeof(c), sizeof(c)); |
| if (ptr != NULL) { |
| emit_int64(c); |
| end_a_const(c1); |
| } |
| return ptr; |
| } |
| address double_constant(jdouble c) { |
| CodeSection* c1 = _code_section; |
| address ptr = start_a_const(sizeof(c), sizeof(c)); |
| if (ptr != NULL) { |
| emit_double(c); |
| end_a_const(c1); |
| } |
| return ptr; |
| } |
| address float_constant(jfloat c) { |
| CodeSection* c1 = _code_section; |
| address ptr = start_a_const(sizeof(c), sizeof(c)); |
| if (ptr != NULL) { |
| emit_float(c); |
| end_a_const(c1); |
| } |
| return ptr; |
| } |
| address address_constant(address c) { |
| CodeSection* c1 = _code_section; |
| address ptr = start_a_const(sizeof(c), sizeof(c)); |
| if (ptr != NULL) { |
| emit_address(c); |
| end_a_const(c1); |
| } |
| return ptr; |
| } |
| address address_constant(address c, RelocationHolder const& rspec) { |
| CodeSection* c1 = _code_section; |
| address ptr = start_a_const(sizeof(c), sizeof(c)); |
| if (ptr != NULL) { |
| relocate(rspec); |
| emit_address(c); |
| end_a_const(c1); |
| } |
| return ptr; |
| } |
| |
| // Bootstrapping aid to cope with delayed determination of constants. |
| // Returns a static address which will eventually contain the constant. |
| // The value zero (NULL) stands instead of a constant which is still uncomputed. |
| // Thus, the eventual value of the constant must not be zero. |
| // This is fine, since this is designed for embedding object field |
| // offsets in code which must be generated before the object class is loaded. |
| // Field offsets are never zero, since an object's header (mark word) |
| // is located at offset zero. |
| RegisterOrConstant delayed_value(int(*value_fn)(), Register tmp, int offset = 0); |
| RegisterOrConstant delayed_value(address(*value_fn)(), Register tmp, int offset = 0); |
| virtual RegisterOrConstant delayed_value_impl(intptr_t* delayed_value_addr, Register tmp, int offset) = 0; |
| // Last overloading is platform-dependent; look in assembler_<arch>.cpp. |
| static intptr_t* delayed_value_addr(int(*constant_fn)()); |
| static intptr_t* delayed_value_addr(address(*constant_fn)()); |
| static void update_delayed_values(); |
| |
| // Bang stack to trigger StackOverflowError at a safe location |
| // implementation delegates to machine-specific bang_stack_with_offset |
| void generate_stack_overflow_check( int frame_size_in_bytes ); |
| virtual void bang_stack_with_offset(int offset) = 0; |
| |
| |
| /** |
| * A platform-dependent method to patch a jump instruction that refers |
| * to this label. |
| * |
| * @param branch the location of the instruction to patch |
| * @param masm the assembler which generated the branch |
| */ |
| void pd_patch_instruction(address branch, address target); |
| |
| }; |
| |
| #ifdef TARGET_ARCH_x86 |
| # include "assembler_x86.hpp" |
| #endif |
| #ifdef TARGET_ARCH_sparc |
| # include "assembler_sparc.hpp" |
| #endif |
| #ifdef TARGET_ARCH_zero |
| # include "assembler_zero.hpp" |
| #endif |
| #ifdef TARGET_ARCH_arm |
| # include "assembler_arm.hpp" |
| #endif |
| #ifdef TARGET_ARCH_ppc |
| # include "assembler_ppc.hpp" |
| #endif |
| #ifdef TARGET_ARCH_aarch64 |
| # include "assembler_aarch64.hpp" |
| #endif |
| |
| |
| #endif // SHARE_VM_ASM_ASSEMBLER_HPP |