Make the dispatcher code position independent so that PIE mode works.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3486

diff --git a/coregrind/amd64/dispatch.S b/coregrind/amd64/dispatch.S
index 1aa1aa4ede0cee0f1b6d092d2b1e09ab9d435a40..fe9bcc0dad534119c5f2f3c0d942fe867e984e5f 100644 (file)
--- a/coregrind/amd64/dispatch.S
+++ b/coregrind/amd64/dispatch.S
@@ -60,7 +60,11 @@ VG_(run_innerloop):
        pushq   %r15
        pushq   %rdi
 
-       /* 0(%rsp) holds cached copy of guest_state */
+       movq    VG_(dispatch_ctr)@GOTPCREL(%rip), %rsi
+       pushq   (%rsi)
+
+       /* 8(%rsp) holds cached copy of guest_state */
+       /* 0(%rsp) holds cached copy of VG_(dispatch_ctr) */
 
        /* Set up the guest state pointer */
        movq    %rdi, %rbp
@@ -95,17 +99,19 @@ dispatch_boring:
        movq    %rax, OFFSET_amd64_RIP(%rbp)
 
        /* Are we out of timeslice?  If yes, defer to scheduler. */
-       subl $1, VG_(dispatch_ctr)
+       subl    $1, 0(%rsp)
        jz      counter_is_zero
 
        /* try a fast lookup in the translation cache */
        movq %rax, %rbx
        andq $VG_TT_FAST_MASK, %rbx
-       movq VG_(tt_fast)(,%rbx,8), %rcx
+       movq VG_(tt_fast)@GOTPCREL(%rip), %rcx
+       movq (%rcx,%rbx,8), %rcx
        cmpq %rax, (%rcx)
        jnz  fast_lookup_failed
        /* increment bb profile counter */
-       movq VG_(tt_fastN)(,%rbx,8), %rdx
+       movq VG_(tt_fastN)@GOTPCREL(%rip), %rdx
+       movq (%rdx,%rbx,8), %rdx
        incl (%rdx)
 
        /* Found a match.  Call tce[1], which is 8 bytes along, since
@@ -118,13 +124,13 @@ dispatch_boring:
           %rbp indicates further details of the control transfer
           requested to the address in %rax.
        
-          If rbp is unchanged (== * 0(%rsp)), just jump next to %rax.
+          If rbp is unchanged (== * 8(%rsp)), just jump next to %rax.
 
           Otherwise fall out, back to the scheduler, and let it
           figure out what to do next.
        */
 
-       cmpq    0(%rsp), %rbp
+       cmpq    8(%rsp), %rbp
        jz      dispatch_boring
 
        jmp     dispatch_exceptional
@@ -157,6 +163,8 @@ invariant_violation:
        jmp     run_innerloop_exit_REALLY
 
 run_innerloop_exit_REALLY:
+       movq    VG_(dispatch_ctr)@GOTPCREL(%rip), %rsi
+       popq    (%rsi)
        popq    %rdi
        popq    %r15
        popq    %r14
@@ -184,20 +192,20 @@ dispatch_exceptional:
        jz      counter_is_zero
 
        /* save %rax in %RIP and defer to sched */
-       movq    0(%rsp), %rdi
+       movq    8(%rsp), %rdi
        movq    %rax, OFFSET_amd64_RIP(%rdi)
        movq    %rbp, %rax
        jmp     run_innerloop_exit
 
 fast_lookup_failed:
        /* %RIP is up to date here since dispatch_boring dominates */
-       addl    $1, VG_(dispatch_ctr)
+       addl    $1, 0(%rsp)
        movq    $VG_TRC_INNER_FASTMISS, %rax
        jmp     run_innerloop_exit
 
 counter_is_zero:
        /* %RIP is up to date here since dispatch_boring dominates */
-       addl    $1, VG_(dispatch_ctr)
+       addl    $1, 0(%rsp)
        movq    $VG_TRC_INNER_COUNTERZERO, %rax
        jmp     run_innerloop_exit