In 32bit mode, removed all assembly addressing modes that are incompatible with

syscall_entrypoint.cc

Index: syscall_entrypoint.cc
===================================================================
--- syscall_entrypoint.cc	(revision 167)
+++ syscall_entrypoint.cc	(working copy)
@@ -176,7 +176,7 @@
     "mov  %ebx, %eax\n"            // NR_exit
     "jmp  0b\n"
   "1:cmp  $173, %eax\n"            // NR_rt_sigreturn
-    "jnz  3f\n"
+    "jnz  4f\n"
 
     // Convert rt_sigframe into sigframe, allowing us to call sigreturn().
     // This is possible since the first part of signal stack frames have
@@ -202,19 +202,21 @@
     "rep movsl\n"
     "mov  0x2C8(%esp), %ebx\n"     // copy first half of signal mask
     "mov  %ebx, 0x54(%esp)\n"
-    "lea  2f, %esi\n"
+    "call 2f\n"
+  "2:pop  %esi\n"
+    "add  $(3f-2b), %esi\n"
     "push %esi\n"                  // push restorer function
     "lea  0x2D4(%esp), %edi\n"     // patch up retcode magic numbers
     "movb $2, %cl\n"
     "rep movsl\n"
     "ret\n"                        // return to restorer function
-  "2:pop  %eax\n"                  // remove dummy argument (signo)
+  "3:pop  %eax\n"                  // remove dummy argument (signo)
     "mov  $119, %eax\n"            // NR_sigaction
     "int  $0x80\n"
 
 
     // Preserve all registers
-  "3:push %ebp\n"
+  "4:push %ebp\n"
     "push $0xDEADBEEF\n"           // marker used by breakpad
     "push %ebx\n"
     "push %ecx\n"
@@ -242,8 +244,12 @@
     "push %eax\n"
 
     // Check range of system call
-    "cmp playground$maxSyscall, %eax\n"
-    "ja  9f\n"
+    "call 5f\n"
+  "5:pop  %edx\n"
+    "add $(_GLOBAL_OFFSET_TABLE_+(.-5b)), %edx\n"
+    "mov playground$maxSyscall@GOT(%edx), %edx\n"
+    "cmp 0(%edx), %eax\n"
+    "ja  14f\n"
 
     // We often have long sequences of calls to gettimeofday(). This is
     // needlessly expensive. Coalesce them into a single call.
@@ -257,9 +263,9 @@
     //               or maybe, if we have recently seen requests to compute
     //               the time. There might be a repeated pattern of those.
     "cmp  $78, %eax\n"             // __NR_gettimeofday
-    "jnz  6f\n"
+    "jnz  10f\n"
     "cmp  %eax, %fs:0x102C-0x58\n" // last system call
-    "jnz  4f\n"
+    "jnz  7f\n"
 
     // This system call and the last system call prior to this one both are
     // calls to gettimeofday(). Try to avoid making the new call and just
@@ -267,44 +273,50 @@
     // Just in case the caller is spinning on the result from gettimeofday(),
     // every so often, call the actual system call.
     "decl %fs:0x1030-0x58\n"       // countdown calls to gettimofday()
-    "jz   4f\n"
+    "jz   7f\n"
 
     // Atomically read the 64bit word representing last-known timestamp and
     // return it to the caller. On x86-32 this is a little more complicated and
     // requires the use of the cmpxchg8b instruction.
     "mov  %ebx, %eax\n"
     "mov  %ecx, %edx\n"
-    "lock; cmpxchg8b 100f\n"
+    "call 6f\n"
+  "6:pop %ebp\n"
+    "add $(100f-6b), %ebp\n"
+    "lock; cmpxchg8b 0(%ebp)\n"
     "mov  %eax, 0(%ebx)\n"
     "mov  %edx, 4(%ebx)\n"
     "xor  %eax, %eax\n"
     "add  $28, %esp\n"
-    "jmp  8f\n"
+    "jmp  13f\n"
 
     // This is a call to gettimeofday(), but we don't have a valid cached
     // result, yet.
-  "4:mov  %eax, %fs:0x102C-0x58\n" // remember syscall number
+  "7:mov  %eax, %fs:0x102C-0x58\n" // remember syscall number
     "movl $500, %fs:0x1030-0x58\n" // make system call, each 500 invocations
-    "call playground$defaultSystemCallHandler\n"
+    "call playground$defaultSystemCallHandler@PLT\n"
 
     // Returned from gettimeofday(). Remember return value, in case the
     // application calls us again right away.
     // Again, this has to happen atomically and requires cmpxchg8b.
     "mov 4(%ebx), %ecx\n"
     "mov 0(%ebx), %ebx\n"
-    "mov 100f, %eax\n"
-    "mov 101f, %edx\n"
-  "5:lock; cmpxchg8b 100f\n"
-    "jnz 5b\n"
+    "call 8f\n"
+  "8:pop %ebp\n"
+    "add $(100f-8b), %ebp\n"
+    "mov 0(%ebp), %eax\n"
+    "mov 4(%ebp), %edx\n"
+  "9:lock; cmpxchg8b 0(%ebp)\n"
+    "jnz 9b\n"
     "xor %eax, %eax\n"
-    "jmp 10f\n"
+    "jmp 15f\n"
 
     // Remember the number of the last system call made. We deliberately do
     // not remember calls to gettid(), as we have often seen long sequences
     // of calls to just gettimeofday() and gettid(). In that situation, we
     // would still like to coalesce the gettimeofday() calls.
-  "6:cmp $224, %eax\n"             // __NR_gettid
-    "jz  7f\n"
+ "10:cmp $224, %eax\n"             // __NR_gettid
+    "jz  11f\n"
     "mov  %eax, %fs:0x102C-0x58\n" // remember syscall number
 
     // Retrieve function call from system call table (c.f.system_call_table.cc)
@@ -312,21 +324,24 @@
     // that should be handled by the defaultSystemCallHandler(); minus one
     // for unrestricted system calls that need to be forwarded to the trusted
     // thread; and function pointers to specific handler functions.
-  "7:shl  $3, %eax\n"
-    "mov  playground$syscallTable, %ebx\n"
-    "add  %ebx, %eax\n"
+ "11:shl  $3, %eax\n"
+    "call 12f\n"
+ "12:pop  %ebx\n"
+    "add  $(_GLOBAL_OFFSET_TABLE_+(.-12b)), %ebx\n"
+    "mov  playground$syscallTable@GOT(%ebx), %ebx\n"
+    "add  0(%ebx), %eax\n"
     "mov  0(%eax), %eax\n"
 
     // Jump to function if non-null and not UNRESTRICTED_SYSCALL, otherwise
     // jump to fallback handler.
     "cmp  $1, %eax\n"
-    "jbe  9f\n"
+    "jbe  14f\n"
     "add  $4, %esp\n"
     "call *%eax\n"
     "add  $24, %esp\n"
 
     // Restore CPU registers, except for %eax which was set by the system call.
-  "8:pop  %esp\n"
+ "13:pop  %esp\n"
     "pop  %edi\n"
     "pop  %esi\n"
     "pop  %edx\n"
@@ -343,14 +358,13 @@
     "ret\n"
 
     // Call default handler.
-  "9:call playground$defaultSystemCallHandler\n"
- "10:add  $28, %esp\n"
-    "jmp 8b\n"
+ "14:call playground$defaultSystemCallHandler@PLT\n"
+ "15:add  $28, %esp\n"
+    "jmp  13b\n"
 
     ".pushsection \".bss\"\n"
     ".balign 8\n"
-"100:.byte 0, 0, 0, 0\n"
-"101:.byte 0, 0, 0, 0\n"
+"100:.byte 0, 0, 0, 0, 0, 0, 0, 0\n"
     ".popsection\n"
 
     #else