X-Git-Url: https://git.xonotic.org/?p=xonotic%2Fgmqcc.git;a=blobdiff_plain;f=fold.c;h=3755608885a216880fd8a4145ac1306a33ccf5a7;hp=60867e8dda031aceaecb8e5badfbf102447ea9c7;hb=ff526954b6303dcbd0c675e3bccfd18abd852624;hpb=aed893b6b8c0fbace708d95767a1ab7e9a6a520b diff --git a/fold.c b/fold.c index 60867e8..3755608 100644 --- a/fold.c +++ b/fold.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2012, 2013, 2014 + * Copyright (C) 2012, 2013, 2014, 2015 * Dale Weiler * * Permission is hereby granted, free of charge, to any person obtaining a copy of @@ -34,15 +34,16 @@ #define FOLD_TINYNESS SFLOAT_TBEFORE /* - * The constant folder is also responsible for validating if the constant - * expressions produce valid results. We cannot trust the FPU control - * unit for these exceptions because setting FPU control words might not - * work. Systems can set and enforce FPU modes of operation. It's also valid - * for libc's to simply ignore FPU exceptions. For instance ARM CPUs in - * glibc. We implement some trivial and IEE 754 conformant functions which - * emulate those operations. This is an entierly optional compiler feature - * which shouldn't be enabled for anything other than performing strict - * passes on constant expressions since it's quite slow. + * Comparing float values is an unsafe operation when the operands to the + * comparison are floating point values that are inexact. For instance 1/3 is an + * inexact value. The FPU is meant to raise exceptions when these sorts of things + * happen, including division by zero, underflows and overflows. The C standard + * library provides us with the header to gain access to the floating- + * point environment and lets us set the rounding mode and check for these exceptions. + * The problem is the standard C library allows an implementation to leave these + * stubbed out and does not require they be implemented. Furthermore, depending + * on implementations there is no control over the FPU. This is an IEE 754 + * conforming implementation in software to compensate. */ typedef uint32_t sfloat_t; @@ -51,7 +52,9 @@ typedef union { sfloat_t s; } sfloat_cast_t; +/* Exception flags */ typedef enum { + SFLOAT_NOEXCEPT = 0, SFLOAT_INVALID = 1, SFLOAT_DIVBYZERO = 4, SFLOAT_OVERFLOW = 8, @@ -59,6 +62,7 @@ typedef enum { SFLOAT_INEXACT = 32 } sfloat_exceptionflags_t; +/* Rounding modes */ typedef enum { SFLOAT_ROUND_NEAREST_EVEN, SFLOAT_ROUND_DOWN, @@ -66,6 +70,7 @@ typedef enum { SFLOAT_ROUND_TO_ZERO } sfloat_roundingmode_t; +/* Underflow tininess-detection mode */ typedef enum { SFLOAT_TAFTER, SFLOAT_TBEFORE @@ -77,7 +82,7 @@ typedef struct { sfloat_tdetect_t tiny; } sfloat_state_t; -/* Count of leading zero bits before the most-significand 1 bit. */ +/* Counts the number of leading zero bits before the most-significand one bit. */ #ifdef _MSC_VER /* MSVC has an intrinsic for this */ static GMQCC_INLINE uint32_t sfloat_clz(uint32_t x) { @@ -114,7 +119,7 @@ typedef struct { #endif /* The value of a NaN */ -#define SFLOAT_NAN 0xFFC00000 +#define SFLOAT_NAN 0xFFFFFFFF /* Test if NaN */ #define SFLOAT_ISNAN(A) \ (0xFF000000 < (uint32_t)((A) << 1)) @@ -123,10 +128,14 @@ typedef struct { (((((A) >> 22) & 0x1FF) == 0x1FE) && ((A) & 0x003FFFFF)) /* Raise exception */ #define SFLOAT_RAISE(STATE, FLAGS) \ - ((STATE)->exceptionflags |= (FLAGS)) + ((STATE)->exceptionflags = (sfloat_exceptionflags_t)((STATE)->exceptionflags | (FLAGS))) /* - * Shifts `A' right `COUNT' bits. Non-zero bits are stored in LSB. Size - * sets the arbitrarly-large limit. + * Shifts `A' right by the number of bits given in `COUNT'. If any non-zero bits + * are shifted off they are forced into the least significand bit of the result + * by setting it to one. As a result of this, the value of `COUNT' can be + * arbitrarily large; if `COUNT' is greater than 32, the result will be either + * zero or one, depending on whether `A' is a zero or non-zero. The result is + * stored into the value pointed by `Z'. */ #define SFLOAT_SHIFT(SIZE, A, COUNT, Z) \ *(Z) = ((COUNT) == 0) \ @@ -134,6 +143,7 @@ typedef struct { : (((COUNT) < (SIZE)) \ ? ((A) >> (COUNT)) | (((A) << ((-(COUNT)) & ((SIZE) - 1))) != 0) \ : ((A) != 0)) + /* Extract fractional component */ #define SFLOAT_EXTRACT_FRAC(X) \ ((uint32_t)((X) & 0x007FFFFF)) @@ -143,21 +153,32 @@ typedef struct { /* Extract sign bit */ #define SFLOAT_EXTRACT_SIGN(X) \ ((X) >> 31) -/* Normalize a subnormal */ +/* + * Normalizes the subnormal value represented by the denormalized significand + * `SA'. The normalized exponent and significand are stored at the locations + * pointed by `Z' and `SZ' respectively. + */ #define SFLOAT_SUBNORMALIZE(SA, Z, SZ) \ - (void)(*(SZ) = (SA) << SFLOAT_CLZ((SA), 8), *(SZ) = 1 - SFLOAT_CLZ((SA), 8)) + (void)(*(SZ) = (SA) << SFLOAT_CLZ((SA), 8), *(Z) = 1 - SFLOAT_CLZ((SA), 8)) /* - * Pack sign, exponent and significand and produce a float. + * Packs the sign `SIGN', exponent `EXP' and significand `SIG' into the value + * giving the result. * - * Integer portions of the significand are added to the exponent. The - * exponent input should be one less than the result exponent whenever - * the significand is normalized since normalized significand will - * always have an integer portion of value one. + * After the shifting into their proper positions, the fields are added together + * to form the result. This means any integer portion of `SIG' will be added + * to the exponent. Similarly, because a properly normalized significand will + * always have an integer portion equal to one, the exponent input `EXP' should + * be one less than the desired result exponent whenever the significant input + * `SIG' is a complete, normalized significand. */ #define SFLOAT_PACK(SIGN, EXP, SIG) \ (sfloat_t)((((uint32_t)(SIGN)) << 31) + (((uint32_t)(EXP)) << 23) + (SIG)) -/* Calculate NaN. If either operands are signaling then raise invalid */ +/* + * Takes two values `a' and `b', one of which is a NaN, and returns the appropriate + * NaN result. If either `a' or `b' is a signaling NaN than an invalid exception is + * raised. + */ static sfloat_t sfloat_propagate_nan(sfloat_state_t *state, sfloat_t a, sfloat_t b) { bool isnan_a = SFLOAT_ISNAN(a); bool issnan_a = SFLOAT_ISSNAN(a); @@ -168,23 +189,33 @@ static sfloat_t sfloat_propagate_nan(sfloat_state_t *state, sfloat_t a, sfloat_t b |= 0x00400000; if (issnan_a | issnan_b) - SFLOAT_RAISE(state, SFLOAT_INEXACT); - if (issnan_a) { - if (issnan_b) - goto larger; - return isnan_b ? b : a; - } else if (isnan_a) { - if (issnan_b | !isnan_b) - return a; -larger: - if ((uint32_t)(a << 1) < (uint32_t)(b << 1)) return b; - if ((uint32_t)(b << 1) < (uint32_t)(a << 1)) return a; - return (a < b) ? a : b; - } + SFLOAT_RAISE(state, SFLOAT_INVALID); + if (isnan_a) + return (issnan_a & isnan_b) ? b : a; return b; } -/* Round and pack */ +/* + * Takes an abstract value having sign `sign_z', exponent `exp_z', and significand + * `sig_z' and returns the appropriate value corresponding to the abstract input. + * + * The abstract value is simply rounded and packed into the format. If the abstract + * input cannot be represented exactly an inexact exception is raised. If the + * abstract input is too large, the overflow and inexact exceptions are both raised + * and an infinity or maximal finite value is returned. If the abstract value is + * too small, the value is rounded to a subnormal and the underflow and inexact + * exceptions are only raised if the value cannot be represented exactly with + * a subnormal. + * + * The input significand `sig_z' has it's binary point between bits 30 and 29, + * this is seven bits to the left of its usual location. The shifted significand + * must be normalized or smaller than this. If it's not normalized then the exponent + * `exp_z' must be zero; in that case, the result returned is a subnormal number + * which must not require rounding. In the more usual case where the significand + * is normalized, the exponent must be one less than the *true* exponent. + * + * The handling of underflow and overflow is otherwise in alignment with IEC/IEEE. + */ static sfloat_t SFLOAT_PACK_round(sfloat_state_t *state, bool sign_z, int16_t exp_z, uint32_t sig_z) { sfloat_roundingmode_t mode = state->roundingmode; bool even = !!(mode == SFLOAT_ROUND_NEAREST_EVEN); @@ -221,13 +252,6 @@ static sfloat_t SFLOAT_PACK_round(sfloat_state_t *state, bool sign_z, int16_t ex SFLOAT_RAISE(state, SFLOAT_UNDERFLOW); } } - - /* - * Significand has point between bits 30 and 29, 7 bits to the left of - * the usual place. This shifted significand has to be normalized - * or smaller, if it isn't the exponent must be zero, in which case - * no rounding occurs since the result will be a subnormal. - */ if (bits) SFLOAT_RAISE(state, SFLOAT_INEXACT); sig_z = (sig_z + increment) >> 7; @@ -237,12 +261,24 @@ static sfloat_t SFLOAT_PACK_round(sfloat_state_t *state, bool sign_z, int16_t ex return SFLOAT_PACK(sign_z, exp_z, sig_z); } -/* Normalized round and pack */ +/* + * Takes an abstract value having sign `sign_z', exponent `exp_z' and significand + * `sig_z' and returns the appropriate value corresponding to the abstract input. + * This function is exactly like `PACK_round' except the significand does not have + * to be normalized. + * + * Bit 31 of the significand must be zero and the exponent must be one less than + * the *true* exponent. + */ static sfloat_t SFLOAT_PACK_normal(sfloat_state_t *state, bool sign_z, int16_t exp_z, uint32_t sig_z) { unsigned char c = SFLOAT_CLZ(sig_z, 1); return SFLOAT_PACK_round(state, sign_z, exp_z - c, sig_z << c); } +/* + * Returns the result of adding the absolute values of `a' and `b'. The sign + * `sign_z' is ignored if the result is a NaN. + */ static sfloat_t sfloat_add_impl(sfloat_state_t *state, sfloat_t a, sfloat_t b, bool sign_z) { int16_t exp_a = SFLOAT_EXTRACT_EXP(a); int16_t exp_b = SFLOAT_EXTRACT_EXP(b); @@ -290,6 +326,11 @@ end: return SFLOAT_PACK_round(state, sign_z, exp_z, sig_z); } +/* + * Returns the result of subtracting the absolute values of `a' and `b'. If the + * sign `sign_z' is one, the difference is negated before being returned. The + * sign is ignored if the result is a NaN. + */ static sfloat_t sfloat_sub_impl(sfloat_state_t *state, sfloat_t a, sfloat_t b, bool sign_z) { int16_t exp_a = SFLOAT_EXTRACT_EXP(a); int16_t exp_b = SFLOAT_EXTRACT_EXP(b); @@ -469,6 +510,12 @@ static sfloat_t sfloat_div(sfloat_state_t *state, sfloat_t a, sfloat_t b) { return SFLOAT_PACK_round(state, sign_z, exp_z, sig_z); } +static sfloat_t sfloat_neg(sfloat_state_t *state, sfloat_t a) { + sfloat_cast_t neg; + neg.f = -1; + return sfloat_mul(state, a, neg.s); +} + static GMQCC_INLINE void sfloat_check(lex_ctx_t ctx, sfloat_state_t *state, const char *vec) { /* Exception comes from vector component */ if (vec) { @@ -493,14 +540,14 @@ static GMQCC_INLINE void sfloat_check(lex_ctx_t ctx, sfloat_state_t *state, cons } static GMQCC_INLINE void sfloat_init(sfloat_state_t *state) { - state->exceptionflags = 0; + state->exceptionflags = SFLOAT_NOEXCEPT; state->roundingmode = FOLD_ROUNDING; state->tiny = FOLD_TINYNESS; } /* * There is two stages to constant folding in GMQCC: there is the parse - * stage constant folding, where, witht he help of the AST, operator + * stage constant folding, where, with the help of the AST, operator * usages can be constant folded. Then there is the constant folding * in the IR for things like eliding if statements, can occur. * @@ -510,6 +557,7 @@ static GMQCC_INLINE void sfloat_init(sfloat_state_t *state) { #define isfloat(X) (((ast_expression*)(X))->vtype == TYPE_FLOAT) #define isvector(X) (((ast_expression*)(X))->vtype == TYPE_VECTOR) #define isstring(X) (((ast_expression*)(X))->vtype == TYPE_STRING) +#define isarray(X) (((ast_expression*)(X))->vtype == TYPE_ARRAY) #define isfloats(X,Y) (isfloat (X) && isfloat (Y)) /* @@ -560,11 +608,11 @@ static GMQCC_INLINE void vec3_soft_eval(vec3_soft_state_t *state, vec3_soft_t sa = vec3_soft_convert(a); vec3_soft_t sb = vec3_soft_convert(b); callback(&state->state[0], sa.x.s, sb.x.s); - if (vec3_soft_exception(state, 0)) state->faults |= VEC_COMP_X; + if (vec3_soft_exception(state, 0)) state->faults = (vec3_comp_t)(state->faults | VEC_COMP_X); callback(&state->state[1], sa.y.s, sb.y.s); - if (vec3_soft_exception(state, 1)) state->faults |= VEC_COMP_Y; + if (vec3_soft_exception(state, 1)) state->faults = (vec3_comp_t)(state->faults | VEC_COMP_Y); callback(&state->state[2], sa.z.s, sb.z.s); - if (vec3_soft_exception(state, 2)) state->faults |= VEC_COMP_Z; + if (vec3_soft_exception(state, 2)) state->faults = (vec3_comp_t)(state->faults | VEC_COMP_Z); } static GMQCC_INLINE void vec3_check_except(vec3_t a, @@ -573,13 +621,14 @@ static GMQCC_INLINE void vec3_check_except(vec3_t a, sfloat_t (*callback)(sfloat_state_t *, sfloat_t, sfloat_t)) { vec3_soft_state_t state; - sfloat_init(&state.state[0]); - sfloat_init(&state.state[1]); - sfloat_init(&state.state[2]); if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) return; + sfloat_init(&state.state[0]); + sfloat_init(&state.state[1]); + sfloat_init(&state.state[2]); + vec3_soft_eval(&state, callback, a, b); if (state.faults & VEC_COMP_X) sfloat_check(ctx, &state.state[0], "x"); if (state.faults & VEC_COMP_Y) sfloat_check(ctx, &state.state[1], "y"); @@ -604,8 +653,31 @@ static GMQCC_INLINE vec3_t vec3_sub(lex_ctx_t ctx, vec3_t a, vec3_t b) { return out; } -static GMQCC_INLINE vec3_t vec3_neg(vec3_t a) { - vec3_t out; +static GMQCC_INLINE vec3_t vec3_neg(lex_ctx_t ctx, vec3_t a) { + vec3_t out; + sfloat_cast_t v[3]; + sfloat_state_t s[3]; + + if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) + goto end; + + v[0].f = a.x; + v[1].f = a.y; + v[2].f = a.z; + + sfloat_init(&s[0]); + sfloat_init(&s[1]); + sfloat_init(&s[2]); + + sfloat_neg(&s[0], v[0].s); + sfloat_neg(&s[1], v[1].s); + sfloat_neg(&s[2], v[2].s); + + sfloat_check(ctx, &s[0], NULL); + sfloat_check(ctx, &s[1], NULL); + sfloat_check(ctx, &s[2], NULL); + +end: out.x = -a.x; out.y = -a.y; out.z = -a.z; @@ -669,11 +741,17 @@ static GMQCC_INLINE vec3_t vec3_not(vec3_t a) { } static GMQCC_INLINE qcfloat_t vec3_mulvv(lex_ctx_t ctx, vec3_t a, vec3_t b) { - vec3_soft_t sa = vec3_soft_convert(a); - vec3_soft_t sb = vec3_soft_convert(b); + vec3_soft_t sa; + vec3_soft_t sb; sfloat_state_t s[5]; sfloat_t r[5]; + if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) + goto end; + + sa = vec3_soft_convert(a); + sb = vec3_soft_convert(b); + sfloat_init(&s[0]); sfloat_init(&s[1]); sfloat_init(&s[2]); @@ -692,15 +770,20 @@ static GMQCC_INLINE qcfloat_t vec3_mulvv(lex_ctx_t ctx, vec3_t a, vec3_t b) { sfloat_check(ctx, &s[3], NULL); sfloat_check(ctx, &s[4], NULL); +end: return (a.x * b.x + a.y * b.y + a.z * b.z); } static GMQCC_INLINE vec3_t vec3_mulvf(lex_ctx_t ctx, vec3_t a, qcfloat_t b) { vec3_t out; - vec3_soft_t sa = vec3_soft_convert(a); + vec3_soft_t sa; sfloat_cast_t sb; sfloat_state_t s[3]; + if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) + goto end; + + sa = vec3_soft_convert(a); sb.f = b; sfloat_init(&s[0]); sfloat_init(&s[1]); @@ -714,6 +797,7 @@ static GMQCC_INLINE vec3_t vec3_mulvf(lex_ctx_t ctx, vec3_t a, qcfloat_t b) { sfloat_check(ctx, &s[1], "y"); sfloat_check(ctx, &s[2], "z"); +end: out.x = a.x * b; out.y = a.y * b; out.z = a.z * b; @@ -742,8 +826,50 @@ static GMQCC_INLINE bool vec3_pbool(vec3_t a) { return (a.x || a.y || a.z); } -static GMQCC_INLINE vec3_t vec3_cross(vec3_t a, vec3_t b) { - vec3_t out; +static GMQCC_INLINE vec3_t vec3_cross(lex_ctx_t ctx, vec3_t a, vec3_t b) { + vec3_t out; + vec3_soft_t sa; + vec3_soft_t sb; + sfloat_t r[9]; + sfloat_state_t s[9]; + + if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) + goto end; + + sa = vec3_soft_convert(a); + sb = vec3_soft_convert(b); + + sfloat_init(&s[0]); + sfloat_init(&s[1]); + sfloat_init(&s[2]); + sfloat_init(&s[3]); + sfloat_init(&s[4]); + sfloat_init(&s[5]); + sfloat_init(&s[6]); + sfloat_init(&s[7]); + sfloat_init(&s[8]); + + r[0] = sfloat_mul(&s[0], sa.y.s, sb.z.s); + r[1] = sfloat_mul(&s[1], sa.z.s, sb.y.s); + r[2] = sfloat_mul(&s[2], sa.z.s, sb.x.s); + r[3] = sfloat_mul(&s[3], sa.x.s, sb.z.s); + r[4] = sfloat_mul(&s[4], sa.x.s, sb.y.s); + r[5] = sfloat_mul(&s[5], sa.y.s, sb.x.s); + r[6] = sfloat_sub(&s[6], r[0], r[1]); + r[7] = sfloat_sub(&s[7], r[2], r[3]); + r[8] = sfloat_sub(&s[8], r[4], r[5]); + + sfloat_check(ctx, &s[0], NULL); + sfloat_check(ctx, &s[1], NULL); + sfloat_check(ctx, &s[2], NULL); + sfloat_check(ctx, &s[3], NULL); + sfloat_check(ctx, &s[4], NULL); + sfloat_check(ctx, &s[5], NULL); + sfloat_check(ctx, &s[6], "x"); + sfloat_check(ctx, &s[7], "y"); + sfloat_check(ctx, &s[8], "z"); + +end: out.x = a.y * b.z - a.z * b.y; out.y = a.z * b.x - a.x * b.z; out.z = a.x * b.y - a.y * b.x; @@ -920,31 +1046,63 @@ ast_expression *fold_constgen_string(fold_t *fold, const char *str, bool transla return (ast_expression*)out; } +typedef union { + void (*callback)(void); + sfloat_t (*binary)(sfloat_state_t *, sfloat_t, sfloat_t); + sfloat_t (*unary)(sfloat_state_t *, sfloat_t); +} float_check_callback_t; + +static bool fold_check_except_float_impl(void (*callback)(void), + fold_t *fold, + ast_value *a, + ast_value *b) +{ + float_check_callback_t call; + sfloat_state_t s; + sfloat_cast_t ca; + + if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS) && !OPTS_WARN(WARN_INEXACT_COMPARES)) + return false; + + call.callback = callback; + sfloat_init(&s); + ca.f = fold_immvalue_float(a); + if (b) { + sfloat_cast_t cb; + cb.f = fold_immvalue_float(b); + call.binary(&s, ca.s, cb.s); + } else { + call.unary(&s, ca.s); + } + + if (s.exceptionflags == 0) + return false; + + if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) + goto inexact_possible; + + sfloat_check(fold_ctx(fold), &s, NULL); + +inexact_possible: + return s.exceptionflags & SFLOAT_INEXACT; +} + +#define fold_check_except_float(CALLBACK, FOLD, A, B) \ + fold_check_except_float_impl(((void (*)(void))(CALLBACK)), (FOLD), (A), (B)) + +static bool fold_check_inexact_float(fold_t *fold, ast_value *a, ast_value *b) { + lex_ctx_t ctx = fold_ctx(fold); + if (!OPTS_WARN(WARN_INEXACT_COMPARES)) + return false; + if (!a->inexact && !b->inexact) + return false; + return compile_warning(ctx, WARN_INEXACT_COMPARES, "inexact value in comparison"); +} static GMQCC_INLINE ast_expression *fold_op_mul_vec(fold_t *fold, vec3_t vec, ast_value *sel, const char *set) { - /* - * vector-component constant folding works by matching the component sets - * to eliminate expensive operations on whole-vectors (3 components at runtime). - * to achive this effect in a clean manner this function generalizes the - * values through the use of a set paramater, which is used as an indexing method - * for creating the elided ast binary expression. - * - * Consider 'n 0 0' where y, and z need to be tested for 0, and x is - * used as the value in a binary operation generating an INSTR_MUL instruction, - * to acomplish the indexing of the correct component value we use set[0], set[1], set[2] - * as x, y, z, where the values of those operations return 'x', 'y', 'z'. Because - * of how ASCII works we can easily deliniate: - * vec.z is the same as set[2]-'x' for when set[2] is 'z', 'z'-'x' results in a - * literal value of 2, using this 2, we know that taking the address of vec->x (float) - * and indxing it with this literal will yeild the immediate address of that component - * - * Of course more work needs to be done to generate the correct index for the ast_member_new - * call, which is no problem: set[0]-'x' suffices that job. - */ qcfloat_t x = (&vec.x)[set[0]-'x']; qcfloat_t y = (&vec.x)[set[1]-'x']; qcfloat_t z = (&vec.x)[set[2]-'x']; - if (!y && !z) { ast_expression *out; ++opts_optimizationcount[OPTIM_VECTOR_COMPONENTS]; @@ -960,11 +1118,14 @@ static GMQCC_INLINE ast_expression *fold_op_mul_vec(fold_t *fold, vec3_t vec, as static GMQCC_INLINE ast_expression *fold_op_neg(fold_t *fold, ast_value *a) { if (isfloat(a)) { - if (fold_can_1(a)) - return fold_constgen_float(fold, -fold_immvalue_float(a), false); + if (fold_can_1(a)) { + /* Negation can produce inexact as well */ + bool inexact = fold_check_except_float(&sfloat_neg, fold, a, NULL); + return fold_constgen_float(fold, -fold_immvalue_float(a), inexact); + } } else if (isvector(a)) { if (fold_can_1(a)) - return fold_constgen_vector(fold, vec3_neg(fold_immvalue_vector(a))); + return fold_constgen_vector(fold, vec3_neg(fold_ctx(fold), fold_immvalue_vector(a))); } return NULL; } @@ -987,44 +1148,6 @@ static GMQCC_INLINE ast_expression *fold_op_not(fold_t *fold, ast_value *a) { return NULL; } -static bool fold_check_except_float(sfloat_t (*callback)(sfloat_state_t *, sfloat_t, sfloat_t), - fold_t *fold, - ast_value *a, - ast_value *b) -{ - sfloat_state_t s; - sfloat_cast_t ca; - sfloat_cast_t cb; - - if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS) && !OPTS_WARN(WARN_INEXACT_COMPARES)) - return false; - - sfloat_init(&s); - ca.f = fold_immvalue_float(a); - cb.f = fold_immvalue_float(b); - - callback(&s, ca.s, cb.s); - if (s.exceptionflags == 0) - return false; - - if (!OPTS_FLAG(ARITHMETIC_EXCEPTIONS)) - goto inexact_possible; - - sfloat_check(fold_ctx(fold), &s, NULL); - -inexact_possible: - return s.exceptionflags & SFLOAT_INEXACT; -} - -static bool fold_check_inexact_float(fold_t *fold, ast_value *a, ast_value *b) { - lex_ctx_t ctx = fold_ctx(fold); - if (!OPTS_WARN(WARN_INEXACT_COMPARES)) - return false; - if (!a->inexact && !b->inexact) - return false; - return compile_warning(ctx, WARN_INEXACT_COMPARES, "inexact value in comparison"); -} - static GMQCC_INLINE ast_expression *fold_op_add(fold_t *fold, ast_value *a, ast_value *b) { if (isfloat(a)) { if (fold_can_2(a, b)) { @@ -1275,7 +1398,17 @@ static GMQCC_INLINE ast_expression *fold_op_bnot(fold_t *fold, ast_value *a) { static GMQCC_INLINE ast_expression *fold_op_cross(fold_t *fold, ast_value *a, ast_value *b) { if (fold_can_2(a, b)) - return fold_constgen_vector(fold, vec3_cross(fold_immvalue_vector(a), fold_immvalue_vector(b))); + return fold_constgen_vector(fold, vec3_cross(fold_ctx(fold), + fold_immvalue_vector(a), + fold_immvalue_vector(b))); + return NULL; +} + +static GMQCC_INLINE ast_expression *fold_op_length(fold_t *fold, ast_value *a) { + if (fold_can_1(a) && isstring(a)) + return fold_constgen_float(fold, strlen(fold_immvalue_string(a)), false); + if (isarray(a)) + return fold_constgen_float(fold, vec_size(a->initlist), false); return NULL; } @@ -1316,29 +1449,30 @@ ast_expression *fold_op(fold_t *fold, const oper_info *info, ast_expression **op return e switch(info->id) { - fold_op_case(2, ('-', 'P'), neg, (fold, a)); - fold_op_case(2, ('!', 'P'), not, (fold, a)); - fold_op_case(1, ('+'), add, (fold, a, b)); - fold_op_case(1, ('-'), sub, (fold, a, b)); - fold_op_case(1, ('*'), mul, (fold, a, b)); - fold_op_case(1, ('/'), div, (fold, a, b)); - fold_op_case(1, ('%'), mod, (fold, a, b)); - fold_op_case(1, ('|'), bor, (fold, a, b)); - fold_op_case(1, ('&'), band, (fold, a, b)); - fold_op_case(1, ('^'), xor, (fold, a, b)); - fold_op_case(1, ('<'), ltgt, (fold, a, b, true)); - fold_op_case(1, ('>'), ltgt, (fold, a, b, false)); - fold_op_case(2, ('<', '<'), lshift, (fold, a, b)); - fold_op_case(2, ('>', '>'), rshift, (fold, a, b)); - fold_op_case(2, ('|', '|'), andor, (fold, a, b, true)); - fold_op_case(2, ('&', '&'), andor, (fold, a, b, false)); - fold_op_case(2, ('?', ':'), tern, (fold, a, b, c)); - fold_op_case(2, ('*', '*'), exp, (fold, a, b)); - fold_op_case(3, ('<','=','>'), lteqgt, (fold, a, b)); - fold_op_case(2, ('!', '='), cmp, (fold, a, b, true)); - fold_op_case(2, ('=', '='), cmp, (fold, a, b, false)); - fold_op_case(2, ('~', 'P'), bnot, (fold, a)); - fold_op_case(2, ('>', '<'), cross, (fold, a, b)); + fold_op_case(2, ('-', 'P'), neg, (fold, a)); + fold_op_case(2, ('!', 'P'), not, (fold, a)); + fold_op_case(1, ('+'), add, (fold, a, b)); + fold_op_case(1, ('-'), sub, (fold, a, b)); + fold_op_case(1, ('*'), mul, (fold, a, b)); + fold_op_case(1, ('/'), div, (fold, a, b)); + fold_op_case(1, ('%'), mod, (fold, a, b)); + fold_op_case(1, ('|'), bor, (fold, a, b)); + fold_op_case(1, ('&'), band, (fold, a, b)); + fold_op_case(1, ('^'), xor, (fold, a, b)); + fold_op_case(1, ('<'), ltgt, (fold, a, b, true)); + fold_op_case(1, ('>'), ltgt, (fold, a, b, false)); + fold_op_case(2, ('<', '<'), lshift, (fold, a, b)); + fold_op_case(2, ('>', '>'), rshift, (fold, a, b)); + fold_op_case(2, ('|', '|'), andor, (fold, a, b, true)); + fold_op_case(2, ('&', '&'), andor, (fold, a, b, false)); + fold_op_case(2, ('?', ':'), tern, (fold, a, b, c)); + fold_op_case(2, ('*', '*'), exp, (fold, a, b)); + fold_op_case(3, ('<','=','>'), lteqgt, (fold, a, b)); + fold_op_case(2, ('!', '='), cmp, (fold, a, b, true)); + fold_op_case(2, ('=', '='), cmp, (fold, a, b, false)); + fold_op_case(2, ('~', 'P'), bnot, (fold, a)); + fold_op_case(2, ('>', '<'), cross, (fold, a, b)); + fold_op_case(3, ('l', 'e', 'n'), length, (fold, a)); } #undef fold_op_case compile_error(fold_ctx(fold), "internal error: attempted to constant-fold for unsupported operator"); @@ -1346,8 +1480,8 @@ ast_expression *fold_op(fold_t *fold, const oper_info *info, ast_expression **op } /* - * Constant folding for compiler intrinsics, simaler approach to operator - * folding, primarly: individual functions for each intrinsics to fold, + * Constant folding for compiler intrinsics, similar approach to operator + * folding, primarily: individual functions for each intrinsics to fold, * and a generic selection function. */ static GMQCC_INLINE ast_expression *fold_intrin_isfinite(fold_t *fold, ast_value *a) {