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authorEmil Velikov <[email protected]>2016-01-18 12:16:48 +0200
committerEmil Velikov <[email protected]>2016-01-26 16:08:33 +0000
commiteb63640c1d38a200a7b1540405051d3ff79d0d8a (patch)
treeda46321a41f309b1d02aeb14d5d5487791c45aeb /src/compiler/glsl/s_expression.cpp
parenta39a8fbbaa129f4e52f2a3ad2747182e9a74d910 (diff)
glsl: move to compiler/
Signed-off-by: Emil Velikov <[email protected]> Acked-by: Matt Turner <[email protected]> Acked-by: Jose Fonseca <[email protected]>
Diffstat (limited to 'src/compiler/glsl/s_expression.cpp')
-rw-r--r--src/compiler/glsl/s_expression.cpp218
1 files changed, 218 insertions, 0 deletions
diff --git a/src/compiler/glsl/s_expression.cpp b/src/compiler/glsl/s_expression.cpp
new file mode 100644
index 00000000000..f82e155a6b6
--- /dev/null
+++ b/src/compiler/glsl/s_expression.cpp
@@ -0,0 +1,218 @@
+/* -*- c++ -*- */
+/*
+ * Copyright © 2010 Intel Corporation
+ *
+ * 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 (including the next
+ * paragraph) 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 <assert.h>
+#include <stdio.h>
+#include <math.h>
+#include "s_expression.h"
+
+s_symbol::s_symbol(const char *str, size_t n)
+{
+ /* Assume the given string is already nul-terminated and in memory that
+ * will live as long as this node.
+ */
+ assert(str[n] == '\0');
+ this->str = str;
+}
+
+s_list::s_list()
+{
+}
+
+static void
+skip_whitespace(const char *&src, char *&symbol_buffer)
+{
+ size_t n = strspn(src, " \v\t\r\n");
+ src += n;
+ symbol_buffer += n;
+ /* Also skip Scheme-style comments: semi-colon 'til end of line */
+ if (src[0] == ';') {
+ n = strcspn(src, "\n");
+ src += n;
+ symbol_buffer += n;
+ skip_whitespace(src, symbol_buffer);
+ }
+}
+
+static s_expression *
+read_atom(void *ctx, const char *&src, char *&symbol_buffer)
+{
+ s_expression *expr = NULL;
+
+ skip_whitespace(src, symbol_buffer);
+
+ size_t n = strcspn(src, "( \v\t\r\n);");
+ if (n == 0)
+ return NULL; // no atom
+
+ // Check for the special symbol '+INF', which means +Infinity. Note: C99
+ // requires strtof to parse '+INF' as +Infinity, but we still support some
+ // non-C99-compliant compilers (e.g. MSVC).
+ if (n == 4 && strncmp(src, "+INF", 4) == 0) {
+ expr = new(ctx) s_float(INFINITY);
+ } else {
+ // Check if the atom is a number.
+ char *float_end = NULL;
+ float f = _mesa_strtof(src, &float_end);
+ if (float_end != src) {
+ char *int_end = NULL;
+ int i = strtol(src, &int_end, 10);
+ // If strtof matched more characters, it must have a decimal part
+ if (float_end > int_end)
+ expr = new(ctx) s_float(f);
+ else
+ expr = new(ctx) s_int(i);
+ } else {
+ // Not a number; return a symbol.
+ symbol_buffer[n] = '\0';
+ expr = new(ctx) s_symbol(symbol_buffer, n);
+ }
+ }
+
+ src += n;
+ symbol_buffer += n;
+
+ return expr;
+}
+
+static s_expression *
+__read_expression(void *ctx, const char *&src, char *&symbol_buffer)
+{
+ s_expression *atom = read_atom(ctx, src, symbol_buffer);
+ if (atom != NULL)
+ return atom;
+
+ skip_whitespace(src, symbol_buffer);
+ if (src[0] == '(') {
+ ++src;
+ ++symbol_buffer;
+
+ s_list *list = new(ctx) s_list;
+ s_expression *expr;
+
+ while ((expr = __read_expression(ctx, src, symbol_buffer)) != NULL) {
+ list->subexpressions.push_tail(expr);
+ }
+ skip_whitespace(src, symbol_buffer);
+ if (src[0] != ')') {
+ printf("Unclosed expression (check your parenthesis).\n");
+ return NULL;
+ }
+ ++src;
+ ++symbol_buffer;
+ return list;
+ }
+ return NULL;
+}
+
+s_expression *
+s_expression::read_expression(void *ctx, const char *&src)
+{
+ assert(src != NULL);
+
+ /* When we encounter a Symbol, we need to save a nul-terminated copy of
+ * the string. However, ralloc_strndup'ing every individual Symbol is
+ * extremely expensive. We could avoid this by simply overwriting the
+ * next character (guaranteed to be whitespace, parens, or semicolon) with
+ * a nul-byte. But overwriting non-whitespace would mess up parsing.
+ *
+ * So, just copy the whole buffer ahead of time. Walk both, leaving the
+ * original source string unmodified, and altering the copy to contain the
+ * necessary nul-bytes whenever we encounter a symbol.
+ */
+ char *symbol_buffer = ralloc_strdup(ctx, src);
+ return __read_expression(ctx, src, symbol_buffer);
+}
+
+void s_int::print()
+{
+ printf("%d", this->val);
+}
+
+void s_float::print()
+{
+ printf("%f", this->val);
+}
+
+void s_symbol::print()
+{
+ printf("%s", this->str);
+}
+
+void s_list::print()
+{
+ printf("(");
+ foreach_in_list(s_expression, expr, &this->subexpressions) {
+ expr->print();
+ if (!expr->next->is_tail_sentinel())
+ printf(" ");
+ }
+ printf(")");
+}
+
+// --------------------------------------------------
+
+bool
+s_pattern::match(s_expression *expr)
+{
+ switch (type)
+ {
+ case EXPR: *p_expr = expr; break;
+ case LIST: if (expr->is_list()) *p_list = (s_list *) expr; break;
+ case SYMBOL: if (expr->is_symbol()) *p_symbol = (s_symbol *) expr; break;
+ case NUMBER: if (expr->is_number()) *p_number = (s_number *) expr; break;
+ case INT: if (expr->is_int()) *p_int = (s_int *) expr; break;
+ case STRING:
+ s_symbol *sym = SX_AS_SYMBOL(expr);
+ if (sym != NULL && strcmp(sym->value(), literal) == 0)
+ return true;
+ return false;
+ };
+
+ return *p_expr == expr;
+}
+
+bool
+s_match(s_expression *top, unsigned n, s_pattern *pattern, bool partial)
+{
+ s_list *list = SX_AS_LIST(top);
+ if (list == NULL)
+ return false;
+
+ unsigned i = 0;
+ foreach_in_list(s_expression, expr, &list->subexpressions) {
+ if (i >= n)
+ return partial; /* More actual items than the pattern expected */
+
+ if (expr == NULL || !pattern[i].match(expr))
+ return false;
+
+ i++;
+ }
+
+ if (i < n)
+ return false; /* Less actual items than the pattern expected */
+
+ return true;
+}