[Valgrind-developers] valgrind: r11786 - in trunk/coregrind: . m_dispatch

[<sv...@va...>]

Author: sewardj
Date: 2011-05-29 10:34:30 +0100 (Sun, 29 May 2011)
New Revision: 11786

Log:
Give the amd64-linux and x86-linux dispatchers two entry points, not one,
so as to avoid a GSP-changed check in the common case.  See vex r2155.
(amd64-darwin and x86-darwin are now temporarily unbuildable.)



Modified:
   trunk/coregrind/m_dispatch/dispatch-amd64-linux.S
   trunk/coregrind/m_dispatch/dispatch-x86-linux.S
   trunk/coregrind/m_translate.c
   trunk/coregrind/pub_core_dispatch.h


Modified: trunk/coregrind/m_dispatch/dispatch-amd64-linux.S
===================================================================
--- trunk/coregrind/m_dispatch/dispatch-amd64-linux.S	2011-05-28 17:07:53 UTC (rev 11785)
+++ trunk/coregrind/m_dispatch/dispatch-amd64-linux.S	2011-05-29 09:34:30 UTC (rev 11786)
@@ -107,8 +107,8 @@
 
 	/* fall into main loop  (the right one) */
 	cmpq	$0, %rsi
-	je	VG_(run_innerloop__dispatch_unprofiled)
-	jmp	VG_(run_innerloop__dispatch_profiled)
+	je	VG_(run_innerloop__dispatch_unassisted_unprofiled)
+	jmp	VG_(run_innerloop__dispatch_unassisted_profiled)
 	/*NOTREACHED*/	
 
 /*----------------------------------------------------*/
@@ -116,16 +116,11 @@
 /*----------------------------------------------------*/
 
 .align	16
-.global	VG_(run_innerloop__dispatch_unprofiled)
-VG_(run_innerloop__dispatch_unprofiled):
-	/* AT ENTRY: %rax is next guest addr, %rbp is possibly
-           modified guest state ptr */
+.global	VG_(run_innerloop__dispatch_unassisted_unprofiled)
+VG_(run_innerloop__dispatch_unassisted_unprofiled):
+	/* AT ENTRY: %rax is next guest addr, %rbp is the
+           unmodified guest state ptr */
 
-	/* Has the guest state pointer been messed with?  If yes,
-	   exit. */
-	testq   $1, %rbp
-	jnz	gsp_changed
-
 	/* save the jump address in the guest state */
 	movq	%rax, OFFSET_amd64_RIP(%rbp)
 
@@ -146,25 +141,32 @@
         /* Found a match.  Jump to .host. */
 	jmp 	*%r11
 	ud2	/* persuade insn decoders not to speculate past here */
-	/* generated code should run, then jump back to
-	   VG_(run_innerloop__dispatch_unprofiled). */
+	/* generated code should run, then jump back to either
+	   VG_(run_innerloop__dispatch_unassisted_unprofiled)
+	   VG_(run_innerloop__dispatch_assisted_unprofiled). */
 	/*NOTREACHED*/
 
+.align	16
+.global	VG_(run_innerloop__dispatch_assisted_unprofiled)
+VG_(run_innerloop__dispatch_assisted_unprofiled):
+	/* AT ENTRY: %rax is next guest addr, %rbp is the
+           modified guest state ptr */
+	/* We know the guest state pointer has been modified.
+	   So jump directly to gsp_changed. */
+	jmp	gsp_changed
+	ud2
+	/*NOTREACHED*/
+
 /*----------------------------------------------------*/
 /*--- PROFILING dispatcher (can be much slower)    ---*/
 /*----------------------------------------------------*/
 
 .align	16
-.global	VG_(run_innerloop__dispatch_profiled)
-VG_(run_innerloop__dispatch_profiled):
-	/* AT ENTRY: %rax is next guest addr, %rbp is possibly
-           modified guest state ptr */
+.global	VG_(run_innerloop__dispatch_unassisted_profiled)
+VG_(run_innerloop__dispatch_unassisted_profiled):
+	/* AT ENTRY: %rax is next guest addr, %rbp is the
+           unmodified guest state ptr */
 
-	/* Has the guest state pointer been messed with?  If yes,
-	   exit. */
-	testq   $1, %rbp
-	jnz	gsp_changed
-
 	/* save the jump address in the guest state */
 	movq	%rax, OFFSET_amd64_RIP(%rbp)
 
@@ -183,7 +185,7 @@
 	jnz	fast_lookup_failed
 
 	/* increment bb profile counter */
-	movq	VG_(tt_fastN)@GOTPCREL(%rip), %rdx
+	movabsq	$VG_(tt_fastN), %rdx
 	shrq	$1, %rbx		/* entry# * sizeof(UInt*) */
 	movq	(%rdx,%rbx,1), %rdx
 	addl	$1, (%rdx)
@@ -191,10 +193,23 @@
         /* Found a match.  Jump to .host. */
 	jmp 	*%r11
 	ud2	/* persuade insn decoders not to speculate past here */
-	/* generated code should run, then jump back to
-	   VG_(run_innerloop__dispatch_profiled). */
+	/* generated code should run, then jump back to either
+	   VG_(run_innerloop__dispatch_unassisted_profiled)
+	   VG_(run_innerloop__dispatch_assisted_profiled). */
 	/*NOTREACHED*/
 
+.align	16
+.global	VG_(run_innerloop__dispatch_assisted_profiled)
+VG_(run_innerloop__dispatch_assisted_profiled):
+	/* AT ENTRY: %rax is next guest addr, %rbp is the
+           modified guest state ptr */
+
+	/* Well, we know the guest state pointer has been modified.
+	   So jump directly to gsp_changed. */
+	jmp	gsp_changed
+	ud2
+	/*NOTREACHED*/
+
 /*----------------------------------------------------*/
 /*--- exit points                                  ---*/
 /*----------------------------------------------------*/

Modified: trunk/coregrind/m_dispatch/dispatch-x86-linux.S
===================================================================
--- trunk/coregrind/m_dispatch/dispatch-x86-linux.S	2011-05-28 17:07:53 UTC (rev 11785)
+++ trunk/coregrind/m_dispatch/dispatch-x86-linux.S	2011-05-29 09:34:30 UTC (rev 11786)
@@ -96,8 +96,8 @@
 	
 	/* fall into main loop (the right one) */
 	cmpl	$0, 32(%esp) /* do_profiling */
-	je	VG_(run_innerloop__dispatch_unprofiled)
-	jmp	VG_(run_innerloop__dispatch_profiled)
+	je	VG_(run_innerloop__dispatch_unassisted_unprofiled)
+	jmp	VG_(run_innerloop__dispatch_unassisted_profiled)
 	/*NOTREACHED*/
 
 /*----------------------------------------------------*/
@@ -105,15 +105,11 @@
 /*----------------------------------------------------*/
 
 .align	16
-.global	VG_(run_innerloop__dispatch_unprofiled)
-VG_(run_innerloop__dispatch_unprofiled):
-	/* AT ENTRY: %eax is next guest addr, %ebp is possibly
-           modified guest state ptr */
+.global	VG_(run_innerloop__dispatch_unassisted_unprofiled)
+VG_(run_innerloop__dispatch_unassisted_unprofiled):
+	/* AT ENTRY: %eax is next guest addr, %ebp is the
+           unmodified guest state ptr */
 
-	/* Has the guest state pointer been messed with?  If yes, exit. */
-	testl	$1, %ebp
-	jnz	gsp_changed
-
 	/* save the jump address in the guest state */
 	movl	%eax, OFFSET_x86_EIP(%ebp)
 
@@ -132,24 +128,32 @@
 	/* Found a match.  Jump to .host. */
 	jmp 	*%edi
 	ud2	/* persuade insn decoders not to speculate past here */
-	/* generated code should run, then jump back to
-	   VG_(run_innerloop__dispatch_unprofiled). */
+	/* generated code should run, then jump back to either
+	   VG_(run_innerloop__dispatch_unassisted_unprofiled) or
+	   VG_(run_innerloop__dispatch_assisted_unprofiled). */
 	/*NOTREACHED*/
 
+.align	16
+.global	VG_(run_innerloop__dispatch_assisted_unprofiled)
+VG_(run_innerloop__dispatch_assisted_unprofiled):
+	/* AT ENTRY: %eax is next guest addr, %ebp is the
+           modified guest state ptr */
+	/* We know the guest state pointer has been modified.
+	   So jump directly to gsp_changed. */
+	jmp	gsp_changed
+	ud2
+	/*NOTREACHED*/
+
 /*----------------------------------------------------*/
 /*--- PROFILING dispatcher (can be much slower)    ---*/
 /*----------------------------------------------------*/
 
 .align	16
-.global	VG_(run_innerloop__dispatch_profiled)
-VG_(run_innerloop__dispatch_profiled):
-	/* AT ENTRY: %eax is next guest addr, %ebp is possibly
-           modified guest state ptr */
+.global	VG_(run_innerloop__dispatch_unassisted_profiled)
+VG_(run_innerloop__dispatch_unassisted_profiled):
+	/* AT ENTRY: %eax is next guest addr, %ebp is the
+           unmodified guest state ptr */
 
-	/* Has the guest state pointer been messed with?  If yes, exit. */
-	testl	$1, %ebp
-	jnz	gsp_changed
-
 	/* save the jump address in the guest state */
 	movl	%eax, OFFSET_x86_EIP(%ebp)
 
@@ -175,10 +179,22 @@
 	/* Found a match.  Jump to .host. */
 	jmp 	*%edi
 	ud2	/* persuade insn decoders not to speculate past here */
-	/* generated code should run, then jump back to
-	   VG_(run_innerloop__dispatch_profiled). */
+	/* generated code should run, then jump back to either
+	   VG_(run_innerloop__dispatch_unassisted_profiled) or
+	   VG_(run_innerloop__dispatch_assisted_profiled). */
 	/*NOTREACHED*/
 
+.align	16
+.global	VG_(run_innerloop__dispatch_assisted_profiled)
+VG_(run_innerloop__dispatch_assisted_profiled):
+	/* AT ENTRY: %eax is next guest addr, %ebp is the
+           modified guest state ptr */
+	/* We know the guest state pointer has been modified.
+	   So jump directly to gsp_changed. */
+	jmp	gsp_changed
+	ud2
+	/*NOTREACHED*/
+
 /*----------------------------------------------------*/
 /*--- exit points                                  ---*/
 /*----------------------------------------------------*/

Modified: trunk/coregrind/m_translate.c
===================================================================
--- trunk/coregrind/m_translate.c	2011-05-28 17:07:53 UTC (rev 11785)
+++ trunk/coregrind/m_translate.c	2011-05-29 09:34:30 UTC (rev 11786)
@@ -1515,23 +1515,38 @@
    /* Set up the dispatch-return info.  For archs without a link
       register, vex generates a jump back to the specified dispatch
       address.  Else, it just generates a branch-to-LR. */
+
 #  if defined(VGA_x86) || defined(VGA_amd64)
-   vta.dispatch 
-      = (!allow_redirection)
-        ? /* It's a no-redir translation.  Will be run with the nonstandard
-           dispatcher VG_(run_a_noredir_translation)
-           and so needs a nonstandard return point. */
-          (void*) &VG_(run_a_noredir_translation__return_point)
+   if (!allow_redirection) {
+      /* It's a no-redir translation.  Will be run with the
+         nonstandard dispatcher VG_(run_a_noredir_translation) and so
+         needs a nonstandard return point. */
+      vta.dispatch_assisted
+         = (void*) &VG_(run_a_noredir_translation__return_point);
+      vta.dispatch_unassisted
+         = vta.dispatch_assisted;
+   }
+   else
+   if (VG_(clo_profile_flags) > 0) {
+      /* normal translation; although we're profiling. */
+      vta.dispatch_assisted
+         = (void*) &VG_(run_innerloop__dispatch_assisted_profiled);
+      vta.dispatch_unassisted
+         = (void*) &VG_(run_innerloop__dispatch_unassisted_profiled);
+   }
+   else {
+      /* normal translation and we're not profiling (the normal case) */
+      vta.dispatch_assisted
+         = (void*) &VG_(run_innerloop__dispatch_assisted_unprofiled);
+      vta.dispatch_unassisted
+         = (void*) &VG_(run_innerloop__dispatch_unassisted_unprofiled);
+   }
 
-        : /* normal translation.  Uses VG_(run_innerloop).  Return
-             point depends on whether we're profiling bbs or not. */
-          VG_(clo_profile_flags) > 0
-          ? (void*) &VG_(run_innerloop__dispatch_profiled)
-          : (void*) &VG_(run_innerloop__dispatch_unprofiled);
 #  elif defined(VGA_ppc32) || defined(VGA_ppc64) \
         || defined(VGA_arm) || defined(VGA_s390x)
    /* See comment libvex.h; machine has link register --> dipatch = NULL */
    vta.dispatch = NULL;
+
 #  else
 #    error "Unknown arch"
 #  endif

Modified: trunk/coregrind/pub_core_dispatch.h
===================================================================
--- trunk/coregrind/pub_core_dispatch.h	2011-05-28 17:07:53 UTC (rev 11785)
+++ trunk/coregrind/pub_core_dispatch.h	2011-05-29 09:34:30 UTC (rev 11786)
@@ -68,8 +68,10 @@
    following somewhat bogus decls.  At least on x86 and amd64.  ppc32
    and ppc64 use straightforward bl-blr to get from dispatcher to
    translation and back and so do not need these labels. */
-extern Addr VG_(run_innerloop__dispatch_unprofiled);
-extern Addr VG_(run_innerloop__dispatch_profiled);
+extern Addr VG_(run_innerloop__dispatch_unassisted_unprofiled);
+extern Addr VG_(run_innerloop__dispatch_assisted_unprofiled);
+extern Addr VG_(run_innerloop__dispatch_unassisted_profiled);
+extern Addr VG_(run_innerloop__dispatch_assisted_profiled);
 #endif