.. default-domain:: ir Intermediate Representation =========================== Instructions ~~~~~~~~~~~~ This document briefly describes which field of struct instruction is used by which operation. Some of those fields are used by almost all instructions, some others are specific to only one or a few instructions. The common ones are: * .src1, .src2, .src3: (pseudo_t) operands of binops or ternary ops. * .src: (pseudo_t) operand of unary ops (alias for .src1). * .target: (pseudo_t) result of unary, binary & ternary ops, is sometimes used otherwise by some others instructions. * .cond: (pseudo_t) input operands for condition (alias .src/.src1) * .type: (symbol*) usually the type of .result, sometimes of the operands Terminators ----------- .. op:: OP_RET Return from subroutine. * .src : returned value (NULL if void) * .type: type of .src .. op:: OP_BR Unconditional branch * .bb_true: destination basic block .. op:: OP_CBR Conditional branch * .cond: condition * .type: type of .cond, must be an integral type * .bb_true, .bb_false: destination basic blocks .. op:: OP_SWITCH Switch / multi-branch * .cond: condition * .type: type of .cond, must be an integral type * .multijmp_list: pairs of case-value - destination basic block .. op:: OP_UNREACH Mark code as unreachable .. op:: OP_COMPUTEDGOTO Computed goto / branch to register * .src: address to branch to (void*) * .multijmp_list: list of possible destination basic blocks Arithmetic binops ----------------- They all follow the same signature: * .src1, .src2: operands (types must be compatible with .target) * .target: result of the operation (must be an integral type) * .type: type of .target .. op:: OP_ADD Integer addition. .. op:: OP_SUB Integer subtraction. .. op:: OP_MUL Integer multiplication. .. op:: OP_DIVU Integer unsigned division. .. op:: OP_DIVS Integer signed division. .. op:: OP_MODU Integer unsigned remainder. .. op:: OP_MODS Integer signed remainder. .. op:: OP_SHL Shift left (integer only) .. op:: OP_LSR Logical Shift right (integer only) .. op:: OP_ASR Arithmetic Shift right (integer only) Floating-point binops --------------------- They all follow the same signature: * .src1, .src2: operands (types must be compatible with .target) * .target: result of the operation (must be a floating-point type) * .type: type of .target .. op:: OP_FADD Floating-point addition. .. op:: OP_FSUB Floating-point subtraction. .. op:: OP_FMUL Floating-point multiplication. .. op:: OP_FDIV Floating-point division. Logical ops ----------- They all follow the same signature: * .src1, .src2: operands (types must be compatible with .target) * .target: result of the operation * .type: type of .target, must be an integral type .. op:: OP_AND Logical AND .. op:: OP_OR Logical OR .. op:: OP_XOR Logical XOR Integer compares ---------------- They all have the following signature: * .src1, .src2: operands (types must be compatible) * .target: result of the operation (0/1 valued integer) * .type: type of .target, must be an integral type .. op:: OP_SET_EQ Compare equal. .. op:: OP_SET_NE Compare not-equal. .. op:: OP_SET_LE Compare less-than-or-equal (signed). .. op:: OP_SET_GE Compare greater-than-or-equal (signed). .. op:: OP_SET_LT Compare less-than (signed). .. op:: OP_SET_GT Compare greater-than (signed). .. op:: OP_SET_B Compare less-than (unsigned). .. op:: OP_SET_A Compare greater-than (unsigned). .. op:: OP_SET_BE Compare less-than-or-equal (unsigned). .. op:: OP_SET_AE Compare greater-than-or-equal (unsigned). Floating-point compares ----------------------- They all have the same signature as the integer compares. The usual 6 operations exist in two versions: 'ordered' and 'unordered'. These operations first check if any operand is a NaN and if it is the case the ordered compares return false and then unordered return true, otherwise the result of the comparison, now guaranteed to be done on non-NaNs, is returned. .. op:: OP_FCMP_OEQ Floating-point compare ordered equal .. op:: OP_FCMP_ONE Floating-point compare ordered not-equal .. op:: OP_FCMP_OLE Floating-point compare ordered less-than-or-equal .. op:: OP_FCMP_OGE Floating-point compare ordered greater-or-equal .. op:: OP_FCMP_OLT Floating-point compare ordered less-than .. op:: OP_FCMP_OGT Floating-point compare ordered greater-than .. op:: OP_FCMP_UEQ Floating-point compare unordered equal .. op:: OP_FCMP_UNE Floating-point compare unordered not-equal .. op:: OP_FCMP_ULE Floating-point compare unordered less-than-or-equal .. op:: OP_FCMP_UGE Floating-point compare unordered greater-or-equal .. op:: OP_FCMP_ULT Floating-point compare unordered less-than .. op:: OP_FCMP_UGT Floating-point compare unordered greater-than .. op:: OP_FCMP_ORD Floating-point compare ordered: return true if both operands are ordered (none of the operands are a NaN) and false otherwise. .. op:: OP_FCMP_UNO Floating-point compare unordered: return false if no operands is ordered and true otherwise. Unary ops --------- .. op:: OP_NOT Logical not. * .src: operand (type must be compatible with .target) * .target: result of the operation * .type: type of .target, must be an integral type .. op:: OP_NEG Integer negation. * .src: operand (type must be compatible with .target) * .target: result of the operation (must be an integral type) * .type: type of .target .. op:: OP_FNEG Floating-point negation. * .src: operand (type must be compatible with .target) * .target: result of the operation (must be a floating-point type) * .type: type of .target .. op:: OP_SYMADDR Create a pseudo corresponding to the address of a symbol. * .src: input symbol (must be a PSEUDO_SYM) * .target: symbol's address .. op:: OP_COPY Copy (only needed after out-of-SSA). * .src: operand (type must be compatible with .target) * .target: result of the operation * .type: type of .target Type conversions ---------------- They all have the following signature: * .src: source value * .orig_type: type of .src * .target: result value * .type: type of .target Currently, a cast to a void pointer is treated like a cast to an unsigned integer of the same size. .. op:: OP_TRUNC Cast from integer to an integer of a smaller size. .. op:: OP_SEXT Cast from integer to an integer of a bigger size with sign extension. .. op:: OP_ZEXT Cast from integer to an integer of a bigger size with zero extension. .. op:: OP_UTPTR Cast from pointer-sized unsigned integer to pointer type. .. op:: OP_PTRTU Cast from pointer type to pointer-sized unsigned integer. .. op:: OP_PTRCAST Cast between pointers. .. op:: OP_FCVTU Conversion from float type to unsigned integer. .. op:: OP_FCVTS Conversion from float type to signed integer. .. op:: OP_UCVTF Conversion from unsigned integer to float type. .. op:: OP_SCVTF Conversion from signed integer to float type. .. op:: OP_FCVTF Conversion between float types. Ternary ops ----------- .. op:: OP_SEL * .src1: condition, must be of integral type * .src2, .src3: operands (types must be compatible with .target) * .target: result of the operation * .type: type of .target .. op:: OP_FMADD Fused multiply-add. * .src1, .src2, .src3: operands (types must be compatible with .target) * .target: result of the operation (must be a floating-point type) * .type: type of .target .. op:: OP_RANGE Range/bounds checking (only used for an unused sparse extension). * .src1: value to be checked * .src2, src3: bound of the value (must be constants?) * .type: type of .src[123]? Memory ops ---------- .. op:: OP_LOAD Load. * .src: base address to load from * .offset: address offset * .target: loaded value * .type: type of .target .. op:: OP_STORE Store. * .src: base address to store to * .offset: address offset * .target: value to be stored * .type: type of .target Others ------ .. op:: OP_SETFVAL Create a pseudo corresponding to a floating-point literal. * .fvalue: the literal's value (long double) * .target: the corresponding pseudo * .type: type of the literal & .target .. op:: OP_SETVAL Create a pseudo corresponding to a string literal or a label-as-value. The value is given as an expression EXPR_STRING or EXPR_LABEL. * .val: (expression) input expression * .target: the resulting value * .type: type of .target, the value .. op:: OP_PHI Phi-node (for SSA form). * .phi_list: phi-operands (type must be compatible with .target) * .target: "result" * .type: type of .target .. op:: OP_PHISOURCE Phi-node source. Like OP_COPY but exclusively used to give a defining instructions (and thus also a type) to *all* OP_PHI operands. * .phi_src: operand (type must be compatible with .target, alias .src) * .target: the "result" PSEUDO_PHI * .type: type of .target * .phi_users: list of phi instructions using the target pseudo .. op:: OP_CALL Function call. * .func: (pseudo_t) the function (can be a symbol or a "register", alias .src)) * .arguments: (pseudo_list) list of the associated arguments * .target: function return value (if any) * .type: type of .target * .fntypes: (symbol_list) list of the function's types: the first entry is the full function type, the next ones are the type of each arguments .. op:: OP_INLINED_CALL Only used as an annotation to show that the instructions just above correspond to a function that have been inlined. * .func: (pseudo_t) the function (must be a symbol, alias .src)) * .arguments: list of pseudos that where the function's arguments * .target: function return value (if any) * .type: type of .target .. op:: OP_SLICE Extract a "slice" from an aggregate. * .base: (pseudo_t) aggregate (alias .src) * .from, .len: offet & size of the "slice" within the aggregate * .target: result * .type: type of .target .. op:: OP_ASM Inlined assembly code. * .string: asm template * .asm_rules: asm constraints, rules Sparse tagging (line numbers, context, whatever) ------------------------------------------------ .. op:: OP_CONTEXT Currently only used for lock/unlock tracking. * .context_expr: unused * .increment: (1 for locking, -1 for unlocking) * .check: (ignore the instruction if 0) Misc ops -------- .. op:: OP_ENTRY Function entry point (no associated semantic). .. op:: OP_BADOP Invalid operation (should never be generated). .. op:: OP_NOP No-op (should never be generated). .. op:: OP_DEATHNOTE Annotation telling the pseudo will be death after the next instruction (other than some other annotation, that is). .. # vim: tabstop=4