From: Matthias Braun <matze@braunis.de>
Date: Sat, 13 Dec 2008 17:56:13 +0000 (+0000)
Subject: introduce fp_no_float_fold flag for frontends which do not query the backends float... 
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=3a5977e21e90a3f51a7601e63cb75f217090b268;p=libfirm

introduce fp_no_float_fold flag for frontends which do not query the backends float arithmetic mode yet

[r24609]
---

diff --git a/include/libfirm/iropt.h b/include/libfirm/iropt.h
index e008edec7..9203ef8e0 100644
--- a/include/libfirm/iropt.h
+++ b/include/libfirm/iropt.h
@@ -51,20 +51,24 @@
  * - fp_model_fast:
  *     Fastest mode. Associative and distributive law allowed at the expense
  *     of floating point accuracy and correctness. Explicit rounding is disabled.
+ * - fp_no_float_fold:
+ *     Avoid floating point constant folding. Usefull for frontends which do not
+ *     create arithmetic operations in the backends arithmetic mode.
  */
 typedef enum _fp_model_t {
-	fp_explicit_rounding  =  1,  /**< Explicit rounding at assignments, typecasts, return
+	fp_explicit_rounding  = (1u << 0),  /**< Explicit rounding at assignments, typecasts, return
 	                                  and function calls. Conv nodes may NOT be removed, even
 	                                  if they look useless. */
-	fp_strict_algebraic   =  2,  /**< Strict adherence to non-associative and non-distributive
+	fp_strict_algebraic   = (1u << 1),  /**< Strict adherence to non-associative and non-distributive
 	                                  algebra unless the same result is guaranteed. */
-	fp_contradictions     =  4,  /**< FP contradictions are enabled. Only for backend. */
-	fp_strict_eval_order  =  8,  /**< FP instructions must be strict evaluated in given order. */
-	fp_exceptions         = 16,  /**< FP exceptions are supported. No reordering that changes
+	fp_contradictions     = (1u << 2),  /**< FP contradictions are enabled. Only for backend. */
+	fp_strict_eval_order  = (1u << 3),  /**< FP instructions must be strict evaluated in given order. */
+	fp_exceptions         = (1u << 4),  /**< FP exceptions are supported. No reordering that changes
 	                                  the exception flow are allowed. Backends must generate
 	                                  synchronized exception code. */
-	fp_environment_access = 32,  /**< FPU environment can be accessed. Even Constant folding
+	fp_environment_access = (1u << 5),  /**< FPU environment can be accessed. Even Constant folding
 	                                  cannot be done. */
+	fp_no_float_fold      = (1u << 6),
 
 	/** Precise floating point model. Default. */
 	fp_model_precise = fp_explicit_rounding|fp_strict_algebraic|fp_contradictions,
diff --git a/ir/ir/iropt.c b/ir/ir/iropt.c
index 265daadb3..92df9f6f2 100644
--- a/ir/ir/iropt.c
+++ b/ir/ir/iropt.c
@@ -6343,7 +6343,8 @@ ir_node *optimize_node(ir_node *n) {
 			unsigned fp_model = get_irg_fp_model(current_ir_graph);
 			int old_fp_mode = tarval_fp_ops_enabled();
 
-			tarval_enable_fp_ops((fp_model & fp_strict_algebraic) == 0);
+			tarval_enable_fp_ops(! (fp_model & fp_no_float_fold));
+
 			/* try to evaluate */
 			tv = computed_value(n);
 			if (tv != tarval_bad) {