Add --param max-unrolled-insns=<n> support

From-SVN: r50787

gcc/ChangeLog

+2002-03-14  Michael Meissner  <meissner@redhat.com>
+
+	* params.def (PARAM_MAX_UNROLLED_INSNS): New macro, default to
+	100, allowing MAX_UNROLLED_INSNS to be overridden.
+
+	* params.h (MAX_UNROLLED_INSNS): Define so it can be overridden by
+	--param.
+
+	* unroll.c (params.h): Include.
+	(MAX_UNROLLED_INSNS): Delete, now in params.h.
+
+	* doc/invoke.texi (--param max-unroll-insns): Document.
+
+	* Makefile.in (unroll.o): Add $(PARAMS_H) dependency.
+
 2002-03-14  Richard Earnshaw  <rearnsha@arm.com>
 
 	* arm.md: Fix warnings about constraints in peepholes and splits.

gcc/Makefile.in

@@ -1483,7 +1483,7 @@ doloop.o : doloop.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) flags.h $(LOOP_H) \
    $(EXPR_H) hard-reg-set.h $(BASIC_BLOCK_H) $(TM_P_H) toplev.h
 unroll.o : unroll.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) insn-config.h function.h \
    $(INTEGRATE_H) $(REGS_H) $(RECOG_H) flags.h $(EXPR_H) $(LOOP_H) toplev.h \
-   hard-reg-set.h varray.h $(BASIC_BLOCK_H) $(TM_P_H) $(PREDICT_H)
+   hard-reg-set.h varray.h $(BASIC_BLOCK_H) $(TM_P_H) $(PREDICT_H) $(PARAMS_H)
 flow.o : flow.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) $(TREE_H) flags.h insn-config.h \
    $(BASIC_BLOCK_H) $(REGS_H) hard-reg-set.h output.h toplev.h $(RECOG_H) \
    function.h except.h $(EXPR_H) ssa.h $(GGC_H) $(TM_P_H)

gcc/doc/invoke.texi

@@ -3851,6 +3851,11 @@ If an function contains more than this many instructions, it
 will not be inlined.  This option is precisely equivalent to
 @option{-finline-limit}.
 
+@item max-unrolled-insns
+The maximum number of instructions that a loop should have if that loop
+is unrolled, and if the loop is unrolled, it determines how many times
+the loop code is unrolled.
+
 @end table
 @end table
 

gcc/params.def

@@ -89,6 +89,13 @@ DEFPARAM(PARAM_MAX_GCSE_PASSES,
 	"max-gcse-passes",
 	"The maximum number of passes to make when doing GCSE",
 	1)
+
+/* This parameter limits the number of insns in a loop that will be unrolled,
+   and by how much the loop is unrolled.  */
+DEFPARAM(PARAM_MAX_UNROLLED_INSNS,
+	 "max-unrolled-insns",
+	 "The maximum number of instructions to consider to unroll in a loop",
+	 100)
 /*
 Local variables:
 mode:c

gcc/params.h

@@ -96,4 +96,6 @@ typedef enum compiler_param
   ((size_t) PARAM_VALUE (PARAM_MAX_GCSE_MEMORY))
 #define MAX_GCSE_PASSES \
   PARAM_VALUE (PARAM_MAX_GCSE_PASSES)
+#define MAX_UNROLLED_INSNS \
+  PARAM_VALUE (PARAM_MAX_UNROLLED_INSNS)
 #endif /* ! GCC_PARAMS_H */

gcc/unroll.c

@@ -147,6 +147,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #include "hard-reg-set.h"
 #include "basic-block.h"
 #include "predict.h"
+#include "params.h"
 
 /* The prime factors looked for when trying to unroll a loop by some
    number which is modulo the total number of iterations.  Just checking
@@ -169,13 +170,6 @@ enum unroll_types
   UNROLL_NAIVE
 };
 
-/* This controls which loops are unrolled, and by how much we unroll
-   them.  */
-
-#ifndef MAX_UNROLLED_INSNS
-#define MAX_UNROLLED_INSNS 100
-#endif
-
 /* Indexed by register number, if non-zero, then it contains a pointer
    to a struct induction for a DEST_REG giv which has been combined with
    one of more address givs.  This is needed because whenever such a DEST_REG