Simplify X86CompilationCallback: always align to 16-byte boundary; don't save EAX/EDX if unnecessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28910 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86JITInfo.cpp b/lib/Target/X86/X86JITInfo.cpp
index 87fca43..a96b4a6 100644
--- a/lib/Target/X86/X86JITInfo.cpp
+++ b/lib/Target/X86/X86JITInfo.cpp
@@ -57,26 +57,28 @@
#endif
"pushl %ebp\n"
"movl %esp, %ebp\n" // Standard prologue
+#if FASTCC_NUM_INT_ARGS_INREGS > 0
"pushl %eax\n"
- "pushl %edx\n" // save EAX/EDX
-#if defined(__CYGWIN__) || defined(__MINGW32__)
+ "pushl %edx\n" // Save EAX/EDX
+#endif
+#if defined(__APPLE__)
+ "andl $-16, %esp\n" // Align ESP on 16-byte boundary
+#endif
+#if defined(__CYGWIN__) || defined(__MINGW32__) || defined(__APPLE__)
"call _X86CompilationCallback2\n"
-#elif defined(__APPLE__)
- "movl 4(%ebp), %eax\n" // load the address of return address
- "movl $24, %edx\n" // if the opcode of the instruction at the
- "cmpb $-51, (%eax)\n" // return address is our 0xCD marker, then
- "movl $12, %eax\n" // subtract 24 from %esp to realign it to 16
- "cmovne %eax, %edx\n" // bytes after the push of edx, the amount to.
- "subl %edx, %esp\n" // the push of edx to keep it aligned.
- "pushl %edx\n" // subtract. Otherwise, subtract 12 bytes after
- "call _X86CompilationCallback2\n"
- "popl %edx\n"
- "addl %edx, %esp\n"
#else
- "call X86CompilationCallback2\n"
+ "call X86CompilationCallback2\n"
+#endif
+#if defined(__APPLE__)
+ "movl %ebp, %esp\n" // Restore ESP
+#endif
+#if FASTCC_NUM_INT_ARGS_INREGS > 0
+#if defined(__APPLE__)
+ "subl $8, %esp\n"
#endif
"popl %edx\n"
"popl %eax\n"
+#endif
"popl %ebp\n"
"ret\n");
#else