re PR target/6542 (Internal compiler error when building libgcc for sparc-elf)

	PR target/6542
	* config/sparc/sparc.h (leaf_reg_remap): Remove const.
	(CONDITIONAL_REGISTER_USAGE): For TARGET_FLAT make
	fill leaf_reg_remap with identity.
	* config/sparc/sparc.c (leaf_reg_remap): Remove const.

	* gcc.dg/20020503-1.c: New test.

From-SVN: r53095

gcc/ChangeLog

+2002-05-03  Jakub Jelinek  <jakub@redhat.com>
+
+	PR target/6542
+	* config/sparc/sparc.h (leaf_reg_remap): Remove const.
+	(CONDITIONAL_REGISTER_USAGE): For TARGET_FLAT make
+	fill leaf_reg_remap with identity.
+	* config/sparc/sparc.c (leaf_reg_remap): Remove const.
+
 2002-05-03  Kazu Hirata  <kazu@cs.umass.edu>
 
 	* config/h8300/crti.asm: Remove trailing spaces.

gcc/config/sparc/sparc.c

@@ -85,7 +85,7 @@ bool sparc_emitting_epilogue;
 /* Vector to say how input registers are mapped to output registers.
    HARD_FRAME_POINTER_REGNUM cannot be remapped by this function to
    eliminate it.  You must use -fomit-frame-pointer to get that.  */
-const char leaf_reg_remap[] =
+char leaf_reg_remap[] =
 { 0, 1, 2, 3, 4, 5, 6, 7,
   -1, -1, -1, -1, -1, -1, 14, -1,
   -1, -1, -1, -1, -1, -1, -1, -1,

gcc/config/sparc/sparc.h

@@ -1014,12 +1014,16 @@ do								\
       fixed_regs[4] = 0;					\
     if (TARGET_FLAT)						\
       {								\
+	int regno;						\
 	/* Let the compiler believe the frame pointer is still	\
 	   %fp, but output it as %i7.  */			\
 	fixed_regs[31] = 1;					\
 	reg_names[HARD_FRAME_POINTER_REGNUM] = "%i7";		\
 	/* Disable leaf functions */				\
 	memset (sparc_leaf_regs, 0, FIRST_PSEUDO_REGISTER);	\
+	/* Make LEAF_REG_REMAP a noop.  */			\
+	for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)	\
+	  leaf_reg_remap [regno] = regno;			\
       }								\
   }								\
 while (0)
@@ -1316,7 +1320,7 @@ extern enum reg_class sparc_regno_reg_class[FIRST_PSEUDO_REGISTER];
 extern char sparc_leaf_regs[];
 #define LEAF_REGISTERS sparc_leaf_regs
 
-extern const char leaf_reg_remap[];
+extern char leaf_reg_remap[];
 #define LEAF_REG_REMAP(REGNO) (leaf_reg_remap[REGNO])
 
 /* The class value for index registers, and the one for base regs.  */

gcc/testsuite/ChangeLog

+2002-05-03  Jakub Jelinek  <jakub@redhat.com>
+
+	* gcc.dg/20020503-1.c: New test.
+
 2002-05-02  Mark Mitchell  <mark@codesourcery.com>
 
 	* g++.dg/init/dtor1.C: Make it tougher.

gcc/testsuite/gcc.dg/20020503-1.c

+/* PR target/6542
+   This testcase caused ICE on SPARC because the function uses no registers
+   after optimizing, so even if -mflat make all registers not permitted
+   for leaf functions, the function was still leaf, but LEAF_REG_REMAP
+   returned -1 for some registers (like %o0).  */
+/* { dg-do compile } */
+/* { do-options "-O2 -g" } */
+/* { do-options "-O2 -g -mflat" { target sparc*-*-* } } */
+
+void foo (char *a, char *b, char *c, char *d)
+{
+}