dyld-95.3.tar.gz

[apple/dyld.git] / src / stub_binding_helper.s

diff --git a/src/stub_binding_helper.s b/src/stub_binding_helper.s
index 4b13088e127a71e80147592e00d1d088fca6af0d..331a5cd6fabc6656f06c0db625d8f80d4bb627be 100644 (file)
--- a/src/stub_binding_helper.s
+++ b/src/stub_binding_helper.s
@@ -26,9 +26,8 @@
 #ifdef __i386__
 /*
  * This is the interface for the stub_binding_helper for i386:
- * The caller has pushed the address of the a lazy pointer to be filled in with
- * the value for the defined symbol and pushed the address of the the mach
- * header this pointer comes from.
+ * The caller has pushed the address of the a lazy pointer to be filled in 
+ * and pushed the address of the the mach header this pointer comes from.
  *
  * sp+4        address of lazy pointer
  * sp+0        address of mach header
@@ -36,24 +35,22 @@
  * Some inter-image function calls pass parameters in registers EAX, ECX, EDX, or XXM0-3,
  * Therefore those registers need to be preserved during the lazy binding.
  * 
- * After the symbol has been resolved and the pointer filled in this is to pop
- * these arguments off the stack and jump to the address of the defined symbol.
+ * After the symbol has been resolved and the lazy pointer filled in, this jumps
+ * to the target address.
  */
-#define MH_PARAM_BP                    4
-#define LP_PARAM_BP                    8
-#define RESULT_BP                      8    /* in order to trash no registers, the target is stored back on the stack then ret it done to it */
-
-#define MH_PARAM_OUT        0
-#define LP_PARAM_OUT        4
-#define EAX_SAVE                       8
-#define ECX_SAVE                       12
-#define EDX_SAVE                       16
-#define XMMM0_SAVE                     32    /* 16-byte align */
-#define XMMM1_SAVE                     48
-#define XMMM2_SAVE                     64
-#define XMMM3_SAVE                     80
-#define STACK_SIZE                     96 /*  (XMMM3_SAVE+16) must be 16 byte aligned too */
-
+#define MH_PARAM_OUT                   0
+#define LP_PARAM_OUT                   4
+#define XMMM0_SAVE                     16      /* 16-byte align */
+#define XMMM1_SAVE                     32
+#define XMMM2_SAVE                     48
+#define XMMM3_SAVE                     64
+#define EAX_SAVE                       84
+#define ECX_SAVE                       88
+#define EDX_SAVE                       92
+#define LP_LOCAL                       96
+#define MH_LOCAL                       100
+#define STACK_SIZE                     100     /* must be 4 mod 16 so that stack winds up 16-byte aliged  */
+#define LP_OLD_BP_SAVE                 104
 
     .text
     .align 4,0x90
@@ -61,38 +58,44 @@
 _fast_stub_binding_helper_interface:
        pushl           $0
     .globl _stub_binding_helper_interface
+    .globl _misaligned_stack_error
 _stub_binding_helper_interface:
-       pushl           %ebp
-       movl            %esp,%ebp
-       subl            $STACK_SIZE,%esp                # at this point stack is 16-byte aligned because two meta-parameters where pushed
-       movl            %eax,EAX_SAVE(%esp)             # save registers that might be used as parameters
+       subl            $STACK_SIZE,%esp            # makes stack 16-byte aligned
+       movl            %eax,EAX_SAVE(%esp)     
+       movl            LP_OLD_BP_SAVE(%esp),%eax   # get lazy-pointer meta-parameter
+       movl            %eax,LP_LOCAL(%esp)     
+       movl            %ebp,LP_OLD_BP_SAVE(%esp)   # store epb back chain
+       movl            %esp,%ebp                   # set epb to be this frame
+       add             $LP_OLD_BP_SAVE,%ebp
        movl            %ecx,ECX_SAVE(%esp)
        movl            %edx,EDX_SAVE(%esp)
+       .align 0,0x90
+_misaligned_stack_error:
        movdqa          %xmm0,XMMM0_SAVE(%esp)
        movdqa          %xmm1,XMMM1_SAVE(%esp)
        movdqa          %xmm2,XMMM2_SAVE(%esp)
        movdqa          %xmm3,XMMM3_SAVE(%esp)
-       movl            MH_PARAM_BP(%ebp),%eax  # call dyld::bindLazySymbol(mh, lazy_ptr)
+_stub_binding_helper_interface2:
+       movl            MH_LOCAL(%esp),%eax     # call dyld::bindLazySymbol(mh, lazy_ptr)
        movl            %eax,MH_PARAM_OUT(%esp)
-       movl            LP_PARAM_BP(%ebp),%eax
+       movl            LP_LOCAL(%esp),%eax
        movl            %eax,LP_PARAM_OUT(%esp)
        call            __ZN4dyld14bindLazySymbolEPK11mach_headerPm
-       movl            %eax,RESULT_BP(%ebp)    # store target for ret
        movdqa          XMMM0_SAVE(%esp),%xmm0  # restore registers
        movdqa          XMMM1_SAVE(%esp),%xmm1
        movdqa          XMMM2_SAVE(%esp),%xmm2
        movdqa          XMMM3_SAVE(%esp),%xmm3
-       movl            EAX_SAVE(%esp),%eax
        movl            ECX_SAVE(%esp),%ecx
        movl            EDX_SAVE(%esp),%edx
-       addl            $STACK_SIZE,%esp
-       popl            %ebp
-       addl            $4,%esp                                 # remove meta-parameter, other meta-parmaeter now holds target for ret
-       ret
+       movl            %eax,%ebp               # move target address to epb
+       movl            EAX_SAVE(%esp),%eax     # restore eaz
+       addl            $STACK_SIZE+4,%esp      # cut back stack
+       xchg            %ebp, (%esp)            # restore ebp and set target to top of stack
+       ret                                     # jump to target
+    
 #endif /* __i386__ */
 
 
-
 #if __x86_64__
 /*
  * This is the interface for the stub_binding_helper for x86_64:
@@ -100,7 +103,7 @@ _stub_binding_helper_interface:
  * the value for the defined symbol and pushed the address of the the mach
  * header this pointer comes from.
  *
- * sp+4        address of lazy pointer
+ * sp+8        address of lazy pointer
  * sp+0        address of mach header
  *
  * All parameters registers must be preserved.
@@ -176,6 +179,7 @@ _stub_binding_helper_interface:
 
 #endif
 
+
 #if __ppc__ || __ppc64__
 #include <architecture/ppc/mode_independent_asm.h>
 /*