Re-apply change 7293097060383bcb75ee9f3e6a270de3b5bee2dc by Thiago Macieira

Re-apply change e2ef97128c006ac2a5c99c67bb54eebaa3b45720 by Thiago Macieira
Implement symbol hiding for JSC's JIT functions.
These functions are implemented directly in assembly, so they need the
proper directives to enable/disable visibility. On ELF systems, it's
.hidden, whereas on Mach-O systems (Mac) it's .private_extern. On
Windows, it's not necessary since you have to explicitly export. I
also implemented the AIX idiom, though it's unlikely anyone will
implement AIX/POWER JIT.

That leaves only HP-UX on PA-RISC unimplemented, from the platforms
that Qt supports. It's also unlikely that we'll imlpement JIT for it.

Reviewed-by: Kent Hansen

(this commit was 26d0990c66068bfc92a2ec77512b26d4a0c11b02, but was
lost during a WebKit update)

1 files changed, 37 insertions, 0 deletions

diff --git a/src/3rdparty/webkit/JavaScriptCore/jit/JITStubs.cpp b/src/3rdparty/webkit/JavaScriptCore/jit/JITStubs.cpp
index 9fa898a..470ed0b 100644
--- a/src/3rdparty/webkit/JavaScriptCore/jit/JITStubs.cpp
+++ b/src/3rdparty/webkit/JavaScriptCore/jit/JITStubs.cpp
@@ -81,6 +81,19 @@ namespace JSC {
 #define SYMBOL_STRING_RELOCATION(name) SYMBOL_STRING(name)
 #endif
 
+#if PLATFORM(DARWIN)
+    // Mach-O platform
+#define HIDE_SYMBOL(name) ".private_extern _" #name
+#elif PLATFORM(AIX)
+    // IBM's own file format
+#define HIDE_SYMBOL(name) ".lglobl " #name
+#elif PLATFORM(LINUX) || PLATFORM(FREEBSD) || PLATFORM(OPENBSD) || PLATFORM(SOLARIS) || (PLATFORM(HPUX) && PLATFORM(IA64)) || PLATFORM(SYMBIAN) || PLATFORM(NETBSD)
+    // ELF platform
+#define HIDE_SYMBOL(name) ".hidden " #name
+#else
+#define HIDE_SYMBOL(name)
+#endif
+
 #if USE(JSVALUE32_64)
 
 #if COMPILER(GCC) && PLATFORM(X86)
@@ -95,6 +108,7 @@ COMPILE_ASSERT(offsetof(struct JITStackFrame, code) == 0x50, JITStackFrame_code_
 asm volatile (
 ".text\n"
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "pushl %ebp" "\n"
     "movl %esp, %ebp" "\n"
@@ -115,6 +129,7 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
 #if !USE(JIT_STUB_ARGUMENT_VA_LIST)
     "movl %esp, %ecx" "\n"
@@ -130,6 +145,7 @@ SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
     
 asm volatile (
 ".globl " SYMBOL_STRING(ctiOpThrowNotCaught) "\n"
+HIDE_SYMBOL(ctiOpThrowNotCaught) "\n"
 SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
     "addl $0x3c, %esp" "\n"
     "popl %ebx" "\n"
@@ -154,6 +170,7 @@ COMPILE_ASSERT(offsetof(struct JITStackFrame, code) == 0x80, JITStackFrame_code_
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "pushq %rbp" "\n"
     "movq %rsp, %rbp" "\n"
@@ -180,6 +197,7 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
     "movq %rsp, %rdi" "\n"
     "call " SYMBOL_STRING_RELOCATION(cti_vm_throw) "\n"
@@ -195,6 +213,7 @@ SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiOpThrowNotCaught) "\n"
+HIDE_SYMBOL(ctiOpThrowNotCaught) "\n"
 SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
     "addq $0x48, %rsp" "\n"
     "popq %rbx" "\n"
@@ -216,6 +235,7 @@ asm volatile (
 ".text" "\n"
 ".align 2" "\n"
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 ".thumb" "\n"
 ".thumb_func " THUMB_FUNC_PARAM(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
@@ -242,6 +262,7 @@ asm volatile (
 ".text" "\n"
 ".align 2" "\n"
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 ".thumb" "\n"
 ".thumb_func " THUMB_FUNC_PARAM(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
@@ -347,7 +368,9 @@ COMPILE_ASSERT(offsetof(struct JITStackFrame, code) == 0x30, JITStackFrame_code_
 COMPILE_ASSERT(offsetof(struct JITStackFrame, savedEBX) == 0x1c, JITStackFrame_stub_argument_space_matches_ctiTrampoline);
 
 asm volatile (
+".text\n"
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "pushl %ebp" "\n"
     "movl %esp, %ebp" "\n"
@@ -368,6 +391,7 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
 #if !USE(JIT_STUB_ARGUMENT_VA_LIST)
     "movl %esp, %ecx" "\n"
@@ -383,6 +407,7 @@ SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
     
 asm volatile (
 ".globl " SYMBOL_STRING(ctiOpThrowNotCaught) "\n"
+HIDE_SYMBOL(ctiOpThrowNotCaught) "\n"
 SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
     "addl $0x1c, %esp" "\n"
     "popl %ebx" "\n"
@@ -405,7 +430,9 @@ COMPILE_ASSERT(offsetof(struct JITStackFrame, code) == 0x48, JITStackFrame_code_
 COMPILE_ASSERT(offsetof(struct JITStackFrame, savedRBX) == 0x78, JITStackFrame_stub_argument_space_matches_ctiTrampoline);
 
 asm volatile (
+".text\n"
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "pushq %rbp" "\n"
     "movq %rsp, %rbp" "\n"
@@ -439,6 +466,7 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
     "movq %rsp, %rdi" "\n"
     "call " SYMBOL_STRING_RELOCATION(cti_vm_throw) "\n"
@@ -454,6 +482,7 @@ SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiOpThrowNotCaught) "\n"
+HIDE_SYMBOL(ctiOpThrowNotCaught) "\n"
 SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
     "addq $0x78, %rsp" "\n"
     "popq %rbx" "\n"
@@ -475,6 +504,7 @@ asm volatile (
 ".text" "\n"
 ".align 2" "\n"
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 ".thumb" "\n"
 ".thumb_func " THUMB_FUNC_PARAM(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
@@ -501,6 +531,7 @@ asm volatile (
 ".text" "\n"
 ".align 2" "\n"
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 ".thumb" "\n"
 ".thumb_func " THUMB_FUNC_PARAM(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
@@ -518,6 +549,7 @@ asm volatile (
 ".text" "\n"
 ".align 2" "\n"
 ".globl " SYMBOL_STRING(ctiOpThrowNotCaught) "\n"
+HIDE_SYMBOL(ctiOpThrowNotCaught) "\n"
 ".thumb" "\n"
 ".thumb_func " THUMB_FUNC_PARAM(ctiOpThrowNotCaught) "\n"
 SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
@@ -532,7 +564,9 @@ SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
 #elif COMPILER(GCC) && PLATFORM(ARM_TRADITIONAL)
 
 asm volatile (
+".text\n"
 ".globl " SYMBOL_STRING(ctiTrampoline) "\n"
+HIDE_SYMBOL(ctiTrampoline) "\n"
 SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "stmdb sp!, {r1-r3}" "\n"
     "stmdb sp!, {r4-r8, lr}" "\n"
@@ -549,12 +583,14 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
 
 asm volatile (
 ".globl " SYMBOL_STRING(ctiVMThrowTrampoline) "\n"
+HIDE_SYMBOL(ctiVMThrowTrampoline) "\n"
 SYMBOL_STRING(ctiVMThrowTrampoline) ":" "\n"
     "mov r0, sp" "\n"
     "bl " SYMBOL_STRING_RELOCATION(cti_vm_throw) "\n"
 
 // Both has the same return sequence
 ".globl " SYMBOL_STRING(ctiOpThrowNotCaught) "\n"
+HIDE_SYMBOL(ctiOpThrowNotCaught) "\n"
 SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
     "add sp, sp, #36" "\n"
     "ldmia sp!, {r4-r8, lr}" "\n"
@@ -889,6 +925,7 @@ static NEVER_INLINE void throwStackOverflowError(CallFrame* callFrame, JSGlobalD
         ".text" "\n" \
         ".align 2" "\n" \
         ".globl " SYMBOL_STRING(cti_##op) "\n" \
+        HIDE_SYMBOL(cti_##op) "\n"             \
         ".thumb" "\n" \
         ".thumb_func " THUMB_FUNC_PARAM(cti_##op) "\n" \
         SYMBOL_STRING(cti_##op) ":" "\n" \