extern struct rtx_def *ix86_compare_op0; /* operand 0 for comparisons */
extern struct rtx_def *ix86_compare_op1; /* operand 1 for comparisons */
\f
+/* To properly truncate FP values into integers, we need to set i387 control
+ word. We can't emit proper mode switching code before reload, as spills
+ generated by reload may truncate values incorrectly, but we still can avoid
+ redundant computation of new control word by the mode switching pass.
+ The fldcw instructions are still emitted redundantly, but this is probably
+ not going to be noticeable problem, as most CPUs do have fast path for
+ the sequence.
+
+ The machinery is to emit simple truncation instructions and split them
+ before reload to instructions having USEs of two memory locations that
+ are filled by this code to old and new control word.
+
+ Post-reload pass may be later used to eliminate the redundant fildcw if
+ needed. */
+
+enum fp_cw_mode {FP_CW_STORED, FP_CW_UNINITIALIZED, FP_CW_ANY};
+
+/* Define this macro if the port needs extra instructions inserted
+ for mode switching in an optimizing compilation. */
+
+#define OPTIMIZE_MODE_SWITCHING(ENTITY) 1
+
+/* If you define `OPTIMIZE_MODE_SWITCHING', you have to define this as
+ initializer for an array of integers. Each initializer element N
+ refers to an entity that needs mode switching, and specifies the
+ number of different modes that might need to be set for this
+ entity. The position of the initializer in the initializer -
+ starting counting at zero - determines the integer that is used to
+ refer to the mode-switched entity in question. */
+
+#define NUM_MODES_FOR_MODE_SWITCHING { FP_CW_ANY }
+
+/* ENTITY is an integer specifying a mode-switched entity. If
+ `OPTIMIZE_MODE_SWITCHING' is defined, you must define this macro to
+ return an integer value not larger than the corresponding element
+ in `NUM_MODES_FOR_MODE_SWITCHING', to denote the mode that ENTITY
+ must be switched into prior to the execution of INSN. */
+
+#define MODE_NEEDED(ENTITY, I) \
+ (GET_CODE (I) == CALL_INSN \
+ || (GET_CODE (I) == INSN && (asm_noperands (PATTERN (I)) >= 0 \
+ || GET_CODE (PATTERN (I)) == ASM_INPUT))\
+ ? FP_CW_UNINITIALIZED \
+ : recog_memoized (I) < 0 || get_attr_type (I) != TYPE_FISTP \
+ ? FP_CW_ANY \
+ : FP_CW_STORED)
+
+/* This macro specifies the order in which modes for ENTITY are
+ processed. 0 is the highest priority. */
+
+#define MODE_PRIORITY_TO_MODE(ENTITY, N) N
+
+/* Generate one or more insns to set ENTITY to MODE. HARD_REG_LIVE
+ is the set of hard registers live at the point where the insn(s)
+ are to be inserted. */
+
+#define EMIT_MODE_SET(ENTITY, MODE, HARD_REGS_LIVE) \
+ (MODE == FP_CW_STORED \
+ ? emit_i387_cw_initialization (assign_386_stack_local (HImode, 1), \
+ assign_386_stack_local (HImode, 2)), 0\
+ : 0)
+
+\f
/*
Local variables:
version-control: t
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