Add hard-coded SEH unwind data for EXITCALL

Author: dstogov

ext/opcache/jit/zend_jit_ir.c

@@ -3233,7 +3233,7 @@ static void zend_jit_setup_unwinder(void)
 	static const unsigned char uw_data[] = {
 		0x01, // UBYTE: 3 Version , UBYTE: 5 Flags
 		0x10, // UBYTE Size of prolog
-		0x09, // UBYTE Count of unwind codes
+		0x0a, // UBYTE Count of unwind codes
 		0x00, // UBYTE: 4 Frame Register, UBYTE: 4 Frame Register offset (scaled)
 		// USHORT * n Unwind codes array
 		0x10, 0x82, // c: subq $0x48, %rsp
@@ -3245,15 +3245,44 @@ static void zend_jit_setup_unwinder(void)
 		0x03, 0x60, // 2: pushq %rsi
 		0x02, 0x50, // 1: pushq %rbp
 		0x01, 0x30, // 0: pushq %rbx
+		0x00, 0x00,
+	};
+	static const unsigned char uw_data_exitcall[] = {
+		0x01, // UBYTE: 3 Version , UBYTE: 5 Flags
+		0x10, // UBYTE Size of prolog
+		0x0a, // UBYTE Count of unwind codes
+		0x00, // UBYTE: 4 Frame Register, UBYTE: 4 Frame Register offset (scaled)
+		// USHORT * n Unwind codes array
+		0x10, 0x01, 0x2f, 0x00, // c: subq 376, %rsp ; 0x48 + 32+16*8+16*8+8+8
+		0x0c, 0xf0, // a: pushq %r15
+		0x0a, 0xe0, // 8: pushq %r14
+		0x08, 0xd0, // 6: pushq %r13
+		0x06, 0xc0, // 4: pushq %r12
+		0x04, 0x70, // 3: pushq %rdi
+		0x03, 0x60, // 2: pushq %rsi
+		0x02, 0x50, // 1: pushq %rbp
+		0x01, 0x30, // 0: pushq %rbx
 	};
 
 	zend_jit_uw_func = (PRUNTIME_FUNCTION)*dasm_ptr;
-	*dasm_ptr = (char*)*dasm_ptr + ZEND_MM_ALIGNED_SIZE_EX(sizeof(RUNTIME_FUNCTION) + sizeof(uw_data), 16);
+	*dasm_ptr = (char*)*dasm_ptr + ZEND_MM_ALIGNED_SIZE_EX(sizeof(RUNTIME_FUNCTION) * 4 +
+		sizeof(uw_data) + sizeof(uw_data_exitcall) + sizeof(uw_data), 16);
+
+	zend_jit_uw_func[0].BeginAddress = 0;
+	zend_jit_uw_func[1].BeginAddress = (uintptr_t)zend_jit_stub_handlers[jit_stub_trace_exit] - (uintptr_t)dasm_buf;
+	zend_jit_uw_func[2].BeginAddress = (uintptr_t)zend_jit_stub_handlers[jit_stub_undefined_offset] - (uintptr_t)dasm_buf;
+
+	zend_jit_uw_func[0].EndAddress = zend_jit_uw_func[1].BeginAddress;
+	zend_jit_uw_func[1].EndAddress = zend_jit_uw_func[2].BeginAddress;
+	zend_jit_uw_func[2].EndAddress = (uintptr_t)dasm_end - (uintptr_t)dasm_buf;
+
+	zend_jit_uw_func[0].UnwindData = (uintptr_t)zend_jit_uw_func  - (uintptr_t)dasm_buf + sizeof(RUNTIME_FUNCTION) * 4;
+	zend_jit_uw_func[1].UnwindData = zend_jit_uw_func[0].UnwindData + sizeof(uw_data);
+	zend_jit_uw_func[2].UnwindData = zend_jit_uw_func[1].UnwindData + sizeof(uw_data_exitcall);
 
-	zend_jit_uw_func->BeginAddress = 0;
-	zend_jit_uw_func->EndAddress = (uintptr_t)dasm_end - (uintptr_t)dasm_buf;
-	zend_jit_uw_func->UnwindData = (uintptr_t)zend_jit_uw_func + sizeof(RUNTIME_FUNCTION) - (uintptr_t)dasm_buf;
-	memcpy((char*)zend_jit_uw_func + sizeof(RUNTIME_FUNCTION), uw_data, sizeof(uw_data));
+	memcpy((char*)dasm_buf + zend_jit_uw_func[0].UnwindData, uw_data, sizeof(uw_data));
+	memcpy((char*)dasm_buf + zend_jit_uw_func[1].UnwindData, uw_data_exitcall, sizeof(uw_data_exitcall));
+	memcpy((char*)dasm_buf + zend_jit_uw_func[2].UnwindData, uw_data, sizeof(uw_data));
 
 #ifdef ZEND_JIT_RT_UNWINDER
 	RtlInstallFunctionTableCallback(
@@ -3264,7 +3293,7 @@ static void zend_jit_setup_unwinder(void)
 		NULL,
 		NULL);
 #else
-	RtlAddFunctionTable(zend_jit_uw_func, 1, (uintptr_t)dasm_buf);
+	RtlAddFunctionTable(zend_jit_uw_func, 3, (uintptr_t)dasm_buf);
 #endif
 }
 #endif