Rewrite Solaris compiler tas() assembly routines, merge i386 and x86_64

assembler files, renamed as solaris_x86.s.

Theo Schlossnagle

src/backend/port/tas/solaris_i386.s

-/=============================================================================
-/ tas.s -- test and set lock for solaris_i386
-/=============================================================================
-
-        .file   "tas.s"
-        .text
-        .align  16
-.L1.text:
-
-        .globl  tas
-tas:
-        pushl   %ebp            /save prev base pointer
-        movl    %esp,%ebp       /new base pointer
-        pushl   %ebx            /save prev bx
-        movl    8(%ebp),%ebx    /load bx with address of lock
-        movl    $255,%eax       /put something in ax
-        xchgb   %al,(%ebx)      /swap lock value with "0"
-        cmpb    $0,%al          /did we get the lock?
-        jne     .Locked
-        subl    %eax,%eax       /yes, we got it -- return 0
-        jmp     .Finish
-        .align  4
-.Locked:
-        movl    $1,%eax         /no, we didn't get it - return 1
-.Finish:
-        popl    %ebx            /restore prev bx
-        movl    %ebp,%esp       /restore stack state
-        popl    %ebp
-        ret                     /return
-        .align  4
-        .type   tas,@function
-        .size   tas,.-tas
-

src/backend/port/tas/solaris_sparc.s

-	!!
-	!! $PostgreSQL: pgsql/src/backend/port/tas/solaris_sparc.s,v 1.2 2003/11/29 19:51:54 pgsql Exp $
-	!!
-	!! this would be a piece of inlined assembler but it appears
-	!! to be easier to just write the assembler than to try to 
-	!! figure out how to make sure that in/out registers are kept
-	!! straight in the asm's.
-	!!
-	.file	"tas.c"
-.section	".text"
-	.align 4
-	.global tas
-	.type	 tas,#function
-	.proc	04
-tas:
-	!!
-	!! this is a leaf procedure - no need to save windows and 
-	!! diddle the CWP.
-	!!
-	!#PROLOGUE# 0
-	!#PROLOGUE# 1
+/=======================================================================
+/ solaris_sparc.s -- compare and swap for solaris_sparc
+/=======================================================================
 
-	!!
-	!! write 0xFF into the lock address, saving the old value in %o0.
-	!! this is an atomic action, even on multiprocessors.
-	!!
-	ldstub [%o0],%o0
+#if defined(__sparcv9) || defined(__sparc)
 
-	!!
-	!! if it was already set when we set it, somebody else already
-	!! owned the lock -- return 1.
-	!!
-	cmp %o0,0
-	bne .LL2
-	mov 1,%o0
+         .section        ".text"
+         .align  8
+         .skip   24
+         .align  4
 
-	!!
-	!! otherwise, it was clear and we now own the lock -- return 0.
-	!!
-	mov 0,%o0
-.LL2:
-	!!
-	!! this is a leaf procedure - no need to restore windows and 
-	!! diddle the CWP.
-	!!
+         .global pg_atomic_cas
+pg_atomic_cas:
+         cas     [%o0],%o2,%o1
+         mov     %o1,%o0
          retl
          nop
-.LLfe1:
-	.size	 tas,.LLfe1-tas
-	.ident	"GCC: (GNU) 2.5.8"
+         .type   pg_atomic_cas,2
+         .size   pg_atomic_cas,(.-pg_atomic_cas)
+#endif

src/backend/port/tas/solaris_x86.s

+/=======================================================================
+/ solaris_i386.s -- compare and swap for solaris_i386
+/=======================================================================
+
+/ Fortunately the Sun compiler understands cpp conditionals
+
+         .file   "tas.s"
+
+#if defined(__amd64)
+         .code64
+#endif
+
+         .globl pg_atomic_cas
+         .type pg_atomic_cas, @function
+
+         .section .text, "ax"
+         .align 16
+
+pg_atomic_cas:
+#if defined(__amd64)
+         movl       %edx,%eax
+         lock
+         cmpxchgl   %esi,(%rdi)
+#else
+         movl    4(%esp), %edx
+         movl    8(%esp), %ecx
+         movl    12(%esp), %eax
+         lock
+         cmpxchgl %ecx, (%edx)
+#endif
+         ret
+         .size pg_atomic_cas, . - pg_atomic_cas

src/backend/port/tas/solaris_x86_64.s

-/=============================================================================
-/ tas.s -- test and set lock for solaris_i386
-/ based on i386 ASM with modifications outlined in:
-/   http://www.x86-64.org/documentation/assembly.
-/ This might require flags:  -xtarget=opteron -xarch=amd64
-/ DB optimization documenation at:
-/   http://developers.sun.com/solaris/articles/mysql_perf_tune.html
-/=============================================================================
-
-        .file   "tas.s"
-        .text
-        .align  16
-.L1.text:
-
-        .globl  tas
-tas:
-        pushq   %rbp            /save prev base pointer
-        movq    %rsp,%rbp       /new base pointer
-        pushq   %rbx            /save prev bx
-        movq    8(%rbp),%rbx    /load bx with address of lock
-        movq    $255,%rax       /put something in ax
-        xchgb   %al,(%rbx)      /swap lock value with "0"
-        cmpb    $0,%al          /did we get the lock?
-        jne     .Locked
-        subq    %rax,%rax       /yes, we got it -- return 0
-        jmp     .Finish
-        .align  8
-.Locked:
-        movq    $1,%rax         /no, we didn't get it - return 1
-.Finish:
-        popq    %rbx            /restore prev bx
-        movq    %rbp,%rsp       /restore stack state
-        popq    %rbp
-        ret                     /return
-        .align  8
-        .type   tas,@function
-        .size   tas,.-tas
-

src/include/storage/s_lock.h

@@ -66,7 +66,7 @@
  * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	  $PostgreSQL: pgsql/src/include/storage/s_lock.h,v 1.149 2006/04/19 23:11:15 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/include/storage/s_lock.h,v 1.150 2006/04/27 22:28:42 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -763,23 +763,14 @@ typedef unsigned char slock_t;
 #endif
 
 
-#if defined(__sparc__) || defined(__sparc)
+#if defined(__sun) && (defined(__i386) || defined(__x86_64__) || defined(__sparc__) || defined(__sparc))
 #define HAS_TEST_AND_SET
-
 typedef unsigned char slock_t;
-#endif
-
-
-/* out-of-line assembler from src/backend/port/tas/foo.s */
 
-/* i386/X86_64 using Sun compiler */
-#if defined(__sun) && (defined(__i386) || defined(__x86_64__)) 
-/*
- * Solaris/386 (we only get here for non-gcc case)
- */
-#define HAS_TEST_AND_SET
+extern volatile slock_t pg_atomic_cas(volatile slock_t *lock, slock_t with,
+									  slock_t cmp);
 
-typedef unsigned char slock_t;
+#define TAS(a) (pg_atomic_cas((a), 1, 0) != 0)
 #endif
 
 

src/template/solaris

@@ -4,29 +4,21 @@ if test "$GCC" != yes ; then
   if test "$enable_debug" != yes; then
     CFLAGS="$CFLAGS -O"		# any optimization breaks debug
   fi
-fi
-
-# Pick right test-and-set (TAS) code.  We need out-of-line assembler
-# when not using gcc.
-case $host in
+else
+  # Pick the right test-and-set (TAS) code for the Sun compiler.
+  # We would like to use in-line assembler, but the compiler
+  # requires *.il files to be on every compile line, making 
+  # the build system too fragile.
+  case $host in
     sparc-*-solaris*)
-	if test "$GCC" != yes ; then
 	need_tas=yes
 	tas_file=solaris_sparc.s
-	fi
     ;;
     i?86-*-solaris*)
-	if test "$GCC" != yes ; then
-		if isainfo | grep amd64
-		then
-			need_tas=yes
-			tas_file=solaris_x86_64.s
-		else
 	need_tas=yes
-			tas_file=solaris_i386.s
-		fi
-	fi
+	tas_file=solaris_x86.s
     ;;
-esac
+  esac
+fi
 
 # -D_POSIX_PTHREAD_SEMANTICS enables 5-arg getpwuid_r, among other things