[committed] Shorten non PIC PA 1.1 calls on hppa-hpux

[John David Anglin]

The enclosed change shortens long PA 1.x calls when not generating PIC
code.  In this case, we can just use space register sr4 for the be and
bel branch instructions, avoiding two instructions to load the space
register of the call destination.  This is always a stub in the current
space.

The rest of the change is cosmetic.  I have been looking at improving
GAS to handle the symbol difference case but it doesn't work yet.

Tested on hppa2.0w-hp-hpux11.11 and hppa64-hp-hpux11.11.

Dave
-- 
J. David Anglin                                  dave.anglin@nrc-cnrc.gc.ca
National Research Council of Canada              (613) 990-0752 (FAX: 952-6602)

2008-03-11  John David Anglin  <dave.anglin@nrc-cnrc.gc.ca>

	* pa.h (TARGET_LONG_PIC_SDIFF_CALL): Conditionalize define on
	TARGET_HPUX.  Revise comment.
	(TARGET_LONG_PIC_PCREL_CALL): Revise comment.
	* pa.c (output_call): Update for revised TARGET_LONG_PIC_SDIFF_CALL.
	Use sr4 variant of `be' instruction when not generating PIC code.
	(attr_length_call): Adjust for above change.

Index: config/pa/pa.h
===================================================================
--- config/pa/pa.h	(revision 133050)
+++ config/pa/pa.h	(working copy)
@@ -101,17 +101,18 @@
    calls.  They are used only in non-pic code.  */
 #define TARGET_LONG_ABS_CALL (TARGET_SOM && !TARGET_GAS)
 
-/* Define to a C expression evaluating to true to use long pic symbol
-   difference calls.  This is a call variant similar to the long pic
-   pc-relative call.  Long pic symbol difference calls are only used with
-   the HP SOM linker.  Currently, only the HP assembler supports these
-   calls.  GAS doesn't allow an arbitrary difference of two symbols.  */
-#define TARGET_LONG_PIC_SDIFF_CALL (!TARGET_GAS)
+/* Define to a C expression evaluating to true to use long PIC symbol
+   difference calls.  Long PIC symbol difference calls are only used with
+   the HP assembler and linker.  The HP assembler detects this instruction
+   sequence and treats it as long pc-relative call.  Currently, GAS only
+   allows a difference of two symbols in the same subspace, and it doesn't
+   detect the sequence as a pc-relative call.  */
+#define TARGET_LONG_PIC_SDIFF_CALL (!TARGET_GAS && TARGET_HPUX)
 
-/* Define to a C expression evaluating to true to use long pic
-   pc-relative calls.  Long pic pc-relative calls are only used with
-   GAS.  Currently, they are usable for calls within a module but
-   not for external calls.  */
+/* Define to a C expression evaluating to true to use long PIC
+   pc-relative calls.  Long PIC pc-relative calls are only used with
+   GAS.  Currently, they are usable for calls which bind local to a
+   module but not for external calls.  */
 #define TARGET_LONG_PIC_PCREL_CALL 0
 
 /* Define to a C expression evaluating to true to use SOM secondary
Index: config/pa/pa.c
===================================================================
--- config/pa/pa.c	(revision 133050)
+++ config/pa/pa.c	(working copy)
@@ -7417,14 +7417,13 @@
     length += 12;
 
   /* long pc-relative branch sequence.  */
-  else if ((TARGET_SOM && TARGET_LONG_PIC_SDIFF_CALL)
-	   || (TARGET_64BIT && !TARGET_GAS)
+  else if (TARGET_LONG_PIC_SDIFF_CALL
 	   || (TARGET_GAS && !TARGET_SOM
 	       && (TARGET_LONG_PIC_PCREL_CALL || local_call)))
     {
       length += 20;
 
-      if (!TARGET_PA_20 && !TARGET_NO_SPACE_REGS)
+      if (!TARGET_PA_20 && !TARGET_NO_SPACE_REGS && flag_pic)
 	length += 8;
     }
 
@@ -7444,7 +7443,7 @@
 	  if (!sibcall)
 	    length += 8;
 
-	  if (!TARGET_NO_SPACE_REGS)
+	  if (!TARGET_NO_SPACE_REGS && flag_pic)
 	    length += 8;
 	}
     }
@@ -7528,7 +7527,7 @@
 	     of increasing length and complexity.  In most cases,
              they don't allow an instruction in the delay slot.  */
 	  if (!((TARGET_LONG_ABS_CALL || local_call) && !flag_pic)
-	      && !(TARGET_SOM && TARGET_LONG_PIC_SDIFF_CALL)
+	      && !TARGET_LONG_PIC_SDIFF_CALL
 	      && !(TARGET_GAS && !TARGET_SOM
 		   && (TARGET_LONG_PIC_PCREL_CALL || local_call))
 	      && !TARGET_64BIT)
@@ -7574,13 +7573,12 @@
 	    }
 	  else
 	    {
-	      if ((TARGET_SOM && TARGET_LONG_PIC_SDIFF_CALL)
-		  || (TARGET_64BIT && !TARGET_GAS))
+	      if (TARGET_LONG_PIC_SDIFF_CALL)
 		{
 		  /* The HP assembler and linker can handle relocations
-		     for the difference of two symbols.  GAS and the HP
-		     linker can't do this when one of the symbols is
-		     external.  */
+		     for the difference of two symbols.  The HP assembler
+		     recognizes the sequence as a pc-relative call and
+		     the linker provides stubs when needed.  */
 		  xoperands[1] = gen_label_rtx ();
 		  output_asm_insn ("{bl|b,l} .+8,%%r1", xoperands);
 		  output_asm_insn ("addil L'%0-%l1,%%r1", xoperands);
@@ -7665,20 +7663,20 @@
 		}
 	      else
 		{
-		  if (!TARGET_NO_SPACE_REGS)
+		  if (!TARGET_NO_SPACE_REGS && flag_pic)
 		    output_asm_insn ("ldsid (%%r1),%%r31\n\tmtsp %%r31,%%sr0",
 				     xoperands);
 
 		  if (sibcall)
 		    {
-		      if (TARGET_NO_SPACE_REGS)
+		      if (TARGET_NO_SPACE_REGS || !flag_pic)
 			output_asm_insn ("be 0(%%sr4,%%r1)", xoperands);
 		      else
 			output_asm_insn ("be 0(%%sr0,%%r1)", xoperands);
 		    }
 		  else
 		    {
-		      if (TARGET_NO_SPACE_REGS)
+		      if (TARGET_NO_SPACE_REGS || !flag_pic)
 			output_asm_insn ("ble 0(%%sr4,%%r1)", xoperands);
 		      else
 			output_asm_insn ("ble 0(%%sr0,%%r1)", xoperands);