+/*
+ * Copyright (C) 2012, 2013
+ * Dale Weiler
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is furnished to do
+ * so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include <string.h>
+#include "ast.h"
+#include "parser.h"
+
+#define FOLD_STRING_UNTRANSLATE_HTSIZE 1024
+#define FOLD_STRING_DOTRANSLATE_HTSIZE 1024
+
+/*
+ * There is two stages to constant folding in GMQCC: there is the parse
+ * stage constant folding, where, witht he 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.
+ *
+ * This file is thus, split into two parts.
+ */
+ast_expression **fold_const_values = NULL;
+
+static GMQCC_INLINE bool fold_possible(const ast_value *val) {
+ return ast_istype((ast_expression*)val, ast_value) &&
+ val->hasvalue && (val->cvq == CV_CONST) &&
+ ((ast_expression*)val)->vtype != TYPE_FUNCTION; /* why not for functions? */
+}
+
+#define isfloat(X) (((ast_expression*)(X))->vtype == TYPE_FLOAT && fold_possible(X))
+#define isvector(X) (((ast_expression*)(X))->vtype == TYPE_VECTOR && fold_possible(X))
+#define isstring(S) (((ast_expression*)(X))->vtype == TYPE_STRING && fold_possible(X))
+#define isfloats(X,Y) (isfloat (X) && isfloat(Y))
+#define isvectors(X,Y) (isvector(X) && isvector(Y))
+#define isstrings(X,Y) (isstring(X) && isstring(Y))
+
+/*
+ * Implementation of basic vector math for vec3_t, for trivial constant
+ * folding.
+ *
+ * TODO: gcc/clang hinting for autovectorization
+ */
+static GMQCC_INLINE vec3_t vec3_add(vec3_t a, vec3_t b) {
+ vec3_t out;
+ out.x = a.x + b.x;
+ out.y = a.y + b.y;
+ out.z = a.z + b.z;
+ return out;
+}
+
+static GMQCC_INLINE vec3_t vec3_sub(vec3_t a, vec3_t b) {
+ vec3_t out;
+ out.x = a.x + b.x;
+ out.y = a.y + b.y;
+ out.z = a.z + b.z;
+ return out;
+}
+
+static GMQCC_INLINE vec3_t vec3_not(vec3_t a) {
+ vec3_t out;
+ out.x = !a.x;
+ out.y = !a.y;
+ out.z = !a.z;
+ return out;
+}
+
+static GMQCC_INLINE vec3_t vec3_neg(vec3_t a) {
+ vec3_t out;
+ out.x = -a.x;
+ out.y = -a.y;
+ out.z = -a.z;
+ return out;
+}
+
+static GMQCC_INLINE vec3_t vec3_xor(vec3_t a, vec3_t b) {
+ vec3_t out;
+ out.x = (qcfloat_t)((qcint_t)a.x ^ (qcint_t)b.x);
+ out.y = (qcfloat_t)((qcint_t)a.y ^ (qcint_t)b.y);
+ out.z = (qcfloat_t)((qcint_t)a.z ^ (qcint_t)b.z);
+ return out;
+}
+
+static GMQCC_INLINE vec3_t vec3_xorvf(vec3_t a, qcfloat_t b) {
+ vec3_t out;
+ out.x = (qcfloat_t)((qcint_t)a.x ^ (qcint_t)b);
+ out.y = (qcfloat_t)((qcint_t)a.y ^ (qcint_t)b);
+ out.z = (qcfloat_t)((qcint_t)a.z ^ (qcint_t)b);
+ return out;
+}
+
+#if 0
+static GMQCC_INLINE qcfloat_t vec3_mulvv(vec3_t a, vec3_t b) {
+ return (a.x * b.x + a.y * b.y + a.z * b.z);
+}
+#endif
+
+static GMQCC_INLINE vec3_t vec3_mulvf(vec3_t a, qcfloat_t b) {
+ vec3_t out;
+ out.x = a.x * b;
+ out.y = a.y * b;
+ out.z = a.z * b;
+ return out;
+}
+
+static GMQCC_INLINE bool vec3_cmp(vec3_t a, vec3_t b) {
+ return a.x == b.x &&
+ a.y == b.y &&
+ a.z == b.z;
+}
+
+static GMQCC_INLINE vec3_t vec3_create(float x, float y, float z) {
+ vec3_t out;
+ out.x = x;
+ out.y = y;
+ out.z = z;
+ return out;
+}
+
+
+static GMQCC_INLINE float fold_immvalue_float(ast_value *expr) {
+ return expr->constval.vfloat;
+}
+static GMQCC_INLINE vec3_t fold_immvalue_vector(ast_value *expr) {
+ return expr->constval.vvec;
+}
+#if 0
+static GMQCC_INLINE const char *fold_immvalue_string(ast_value *expr) {
+ return expr->constval.vstring;
+}
+#endif
+
+
+fold_t *fold_init(parser_t *parser) {
+ fold_t *fold = (fold_t*)mem_a(sizeof(fold_t));
+ fold->parser = parser;
+ fold->imm_float = NULL;
+ fold->imm_vector = NULL;
+ fold->imm_string = NULL;
+ fold->imm_string_untranslate = util_htnew(FOLD_STRING_UNTRANSLATE_HTSIZE);
+ fold->imm_string_dotranslate = util_htnew(FOLD_STRING_DOTRANSLATE_HTSIZE);
+
+ /*
+ * prime the tables with common constant values at constant
+ * locations.
+ */
+ (void)fold_constgen_float (fold, 0.0f);
+ (void)fold_constgen_float (fold, 1.0f);
+ (void)fold_constgen_float (fold, -1.0f);
+
+ (void)fold_constgen_vector(fold, vec3_create(0.0f, 0.0f, 0.0f));
+
+ return fold;
+}
+
+bool fold_generate(fold_t *fold, ir_builder *ir) {
+ /* generate globals for immediate folded values */
+ size_t i;
+ ast_value *cur;
+
+ for (i = 0; i < vec_size(fold->imm_float); ++i)
+ if (!ast_global_codegen ((cur = fold->imm_float[i]), ir, false)) goto err;
+ for (i = 0; i < vec_size(fold->imm_vector); ++i)
+ if (!ast_global_codegen((cur = fold->imm_vector[i]), ir, false)) goto err;
+ for (i = 0; i < vec_size(fold->imm_string); ++i)
+ if (!ast_global_codegen((cur = fold->imm_string[i]), ir, false)) goto err;
+
+ return true;
+
+err:
+ con_out("failed to generate global %s\n", cur->name);
+ ir_builder_delete(ir);
+ return false;
+}
+
+void fold_cleanup(fold_t *fold) {
+ size_t i;
+
+ for (i = 0; i < vec_size(fold->imm_float); ++i) ast_delete(fold->imm_float[i]);
+ for (i = 0; i < vec_size(fold->imm_vector); ++i) ast_delete(fold->imm_vector[i]);
+ for (i = 0; i < vec_size(fold->imm_string); ++i) ast_delete(fold->imm_string[i]);
+
+ vec_free(fold->imm_float);
+ vec_free(fold->imm_vector);
+ vec_free(fold->imm_string);
+
+ util_htdel(fold->imm_string_untranslate);
+ util_htdel(fold->imm_string_dotranslate);
+
+ mem_d(fold);
+}
+
+static lex_ctx_t fold_ctx(fold_t *fold) {
+ lex_ctx_t ctx;
+ if (fold->parser->lex)
+ return parser_ctx(fold->parser);
+
+ memset(&ctx, 0, sizeof(ctx));
+ return ctx;
+}
+
+ast_expression *fold_constgen_float(fold_t *fold, qcfloat_t value) {
+ ast_value *out = NULL;
+ size_t i;
+
+ for (i = 0; i < vec_size(fold->imm_float); i++) {
+ if (fold->imm_float[i]->constval.vfloat == value)
+ return (ast_expression*)fold->imm_float[i];
+ }
+
+ out = ast_value_new(fold_ctx(fold), "#IMMEDIATE", TYPE_FLOAT);
+ out->cvq = CV_CONST;
+ out->hasvalue = true;
+ out->constval.vfloat = value;
+
+ vec_push(fold->imm_float, out);
+
+ return (ast_expression*)out;
+}
+
+ast_expression *fold_constgen_vector(fold_t *fold, vec3_t value) {
+ ast_value *out;
+ size_t i;
+
+ for (i = 0; i < vec_size(fold->imm_vector); i++) {
+ if (vec3_cmp(fold->imm_vector[i]->constval.vvec, value))
+ return (ast_expression*)fold->imm_vector[i];
+ }
+
+ out = ast_value_new(fold_ctx(fold), "#IMMEDIATE", TYPE_VECTOR);
+ out->cvq = CV_CONST;
+ out->hasvalue = true;
+ out->constval.vvec = value;
+
+ vec_push(fold->imm_vector, out);
+
+ return (ast_expression*)out;
+}
+
+ast_expression *fold_constgen_string(fold_t *fold, const char *str, bool translate) {
+ hash_table_t *table = (translate) ? fold->imm_string_untranslate : fold->imm_string_dotranslate;
+ ast_value *out = NULL;
+ size_t hash = util_hthash(table, str);
+
+ if ((out = (ast_value*)util_htgeth(table, str, hash)))
+ return (ast_expression*)out;
+
+ if (translate) {
+ char name[32];
+ util_snprintf(name, sizeof(name), "dotranslate_%lu", (unsigned long)(fold->parser->translated++));
+ out = ast_value_new(parser_ctx(fold->parser), name, TYPE_STRING);
+ out->expression.flags |= AST_FLAG_INCLUDE_DEF; /* def needs to be included for translatables */
+ } else
+ out = ast_value_new(fold_ctx(fold), "#IMMEDIATE", TYPE_STRING);
+
+ out->cvq = CV_CONST;
+ out->hasvalue = true;
+ out->isimm = true;
+ out->constval.vstring = parser_strdup(str);
+
+ vec_push(fold->imm_string, out);
+ util_htseth(table, str, hash, out);
+
+ return (ast_expression*)out;
+}
+
+ast_expression *fold_op(fold_t *fold, const oper_info *info, ast_expression **opexprs) {
+ ast_value *a = (ast_value*)opexprs[0];
+ ast_value *b = (ast_value*)opexprs[1];
+ ast_value *c = (ast_value*)opexprs[2];
+
+ /* can a fold operation be applied to this operator usage? */
+ if (!info->folds)
+ return NULL;
+
+ switch(info->operands) {
+ case 3: if(!c) return NULL;
+ case 2: if(!b) return NULL;
+ }
+
+ switch(info->id) {
+ case opid2('-', 'P'):
+ return isfloat (a) ? fold_constgen_float (fold, fold_immvalue_float(a))
+ : isvector(a) ? fold_constgen_vector(fold, vec3_neg(fold_immvalue_vector(a)))
+ : NULL;
+ case opid2('!', 'P'):
+ return isfloat (a) ? fold_constgen_float (fold, !fold_immvalue_float(a))
+ : isvector(a) ? fold_constgen_vector(fold, vec3_not(fold_immvalue_vector(a)))
+ : NULL;
+ case opid1('+'):
+ return isfloats(a,b) ? fold_constgen_float (fold, fold_immvalue_float(a) + fold_immvalue_float(b))
+ : isvectors(a,b) ? fold_constgen_vector(fold, vec3_add(fold_immvalue_vector(a), fold_immvalue_vector(b)))
+ : NULL;
+ case opid1('-'):
+ return isfloats(a,b) ? fold_constgen_float (fold, fold_immvalue_float(a) - fold_immvalue_float(b))
+ : isvectors(a,b) ? fold_constgen_vector(fold, vec3_sub(fold_immvalue_vector(a), fold_immvalue_vector(b)))
+ : NULL;
+ case opid1('*'):
+ if (isfloat(a))
+ return isvector(b) ? fold_constgen_vector(fold, vec3_mulvf(fold_immvalue_vector(b), fold_immvalue_float(a)))
+ : fold_constgen_float (fold, fold_immvalue_float(a) * fold_immvalue_float(b));
+ return NULL;
+ case opid1('/'):
+ return isfloats(a,b) ? fold_constgen_float (fold, fold_immvalue_float(a) / fold_immvalue_float(b))
+ : isvector(a)&&isfloat(b) ? fold_constgen_vector(fold, vec3_mulvf(fold_immvalue_vector(a), 1.0f / fold_immvalue_float(b)))
+ : NULL;
+ case opid1('%'):
+ return isfloats(a,b) ? fold_constgen_float (fold, (qcfloat_t)(((qcint_t)fold_immvalue_float(a)) % ((qcint_t)fold_immvalue_float(b))))
+ : NULL;
+ case opid1('|'):
+ return isfloats(a,b) ? fold_constgen_float (fold, (qcfloat_t)(((qcint_t)fold_immvalue_float(a)) | ((qcint_t)fold_immvalue_float(b))))
+ : NULL;
+ case opid1('&'):
+ return isfloats(a,b) ? fold_constgen_float (fold, (qcfloat_t)(((qcint_t)fold_immvalue_float(a)) & ((qcint_t)fold_immvalue_float(b))))
+ : NULL;
+ case opid1('^'):
+ return isfloats(a,b) ? fold_constgen_float (fold, (qcfloat_t)(((qcint_t)fold_immvalue_float(a)) ^ ((qcint_t)fold_immvalue_float(b))))
+ : isvectors(a,b) ? fold_constgen_vector(fold, vec3_xor (fold_immvalue_vector(a), fold_immvalue_vector(b)))
+ : isvector(a)&&isfloat(b) ? fold_constgen_vector(fold, vec3_xorvf(fold_immvalue_vector(a), fold_immvalue_float (b)))
+ : NULL;
+ case opid2('<','<'):
+ return isfloats(a,b) ? fold_constgen_float (fold, (qcfloat_t)(((qcuint_t)(fold_immvalue_float(a)) << ((qcuint_t)fold_immvalue_float(b)))))
+ : NULL;
+ case opid2('>','>'):
+ return isfloats(a,b) ? fold_constgen_float (fold, (qcfloat_t)(((qcuint_t)(fold_immvalue_float(a)) >> ((qcuint_t)fold_immvalue_float(b)))))
+ : NULL;
+ case opid2('|','|'): return NULL;
+ case opid2('&','&'): return NULL;
+ case opid2('?',':'): return NULL;
+ case opid2('*','*'): return NULL;
+ case opid3('<','=','>'): return NULL;
+ case opid2('!','='):
+ return isfloats(a,b) ? fold_constgen_float (fold, fold_immvalue_float(a) != fold_immvalue_float(b))
+ : NULL;
+ case opid2('=','='):
+ return isfloats(a,b) ? fold_constgen_float (fold, fold_immvalue_float(a) == fold_immvalue_float(b))
+ : NULL;
+ case opid2('~','P'):
+ return isfloat(a) ? fold_constgen_float (fold, ~(qcint_t)fold_immvalue_float(a))
+ : NULL;
+ break;
+ }
+ return NULL;
+}