Kernel: Simplify kernel entry points slightly

It was silly to push the address of the stack pointer when we can also
just change the callee argument to be a value type.

3 files changed, 38 insertions, 46 deletions

diff --git a/Kernel/Arch/i386/CPU.cpp b/Kernel/Arch/i386/CPU.cpp
index ab98e63454..738dcf35b3 100644
--- a/Kernel/Arch/i386/CPU.cpp
+++ b/Kernel/Arch/i386/CPU.cpp
@@ -62,40 +62,38 @@ asm(
     "    add $0x4, %esp\n"
     "    iret\n");
 
-#define EH_ENTRY(ec)                                         \
-    extern "C" void exception_##ec##_handler(RegisterDump&); \
-    extern "C" void exception_##ec##_entry();                \
-    asm(                                                     \
-        ".globl exception_" #ec "_entry\n"                   \
-        "exception_" #ec "_entry: \n"                        \
-        "    pusha\n"                                        \
-        "    pushw %ds\n"                                    \
-        "    pushw %es\n"                                    \
-        "    pushw %fs\n"                                    \
-        "    pushw %gs\n"                                    \
-        "    pushw %ss\n"                                    \
-        "    pushw %ss\n"                                    \
-        "    pushw %ss\n"                                    \
-        "    pushw %ss\n"                                    \
-        "    pushw %ss\n"                                    \
-        "    popw %ds\n"                                     \
-        "    popw %es\n"                                     \
-        "    popw %fs\n"                                     \
-        "    popw %gs\n"                                     \
-        "    pushl %esp\n"                                   \
-        "    call exception_" #ec "_handler\n"               \
-        "    add $4, %esp\n"                                 \
-        "    popw %gs\n"                                     \
-        "    popw %gs\n"                                     \
-        "    popw %fs\n"                                     \
-        "    popw %es\n"                                     \
-        "    popw %ds\n"                                     \
-        "    popa\n"                                         \
-        "    add $0x4, %esp\n"                               \
+#define EH_ENTRY(ec)                                        \
+    extern "C" void exception_##ec##_handler(RegisterDump); \
+    extern "C" void exception_##ec##_entry();               \
+    asm(                                                    \
+        ".globl exception_" #ec "_entry\n"                  \
+        "exception_" #ec "_entry: \n"                       \
+        "    pusha\n"                                       \
+        "    pushw %ds\n"                                   \
+        "    pushw %es\n"                                   \
+        "    pushw %fs\n"                                   \
+        "    pushw %gs\n"                                   \
+        "    pushw %ss\n"                                   \
+        "    pushw %ss\n"                                   \
+        "    pushw %ss\n"                                   \
+        "    pushw %ss\n"                                   \
+        "    pushw %ss\n"                                   \
+        "    popw %ds\n"                                    \
+        "    popw %es\n"                                    \
+        "    popw %fs\n"                                    \
+        "    popw %gs\n"                                    \
+        "    call exception_" #ec "_handler\n"              \
+        "    popw %gs\n"                                    \
+        "    popw %gs\n"                                    \
+        "    popw %fs\n"                                    \
+        "    popw %es\n"                                    \
+        "    popw %ds\n"                                    \
+        "    popa\n"                                        \
+        "    add $0x4, %esp\n"                              \
         "    iret\n");
 
 #define EH_ENTRY_NO_CODE(ec)                                 \
-    extern "C" void exception_##ec##_handler(RegisterDump&); \
+    extern "C" void exception_##ec##_handler(RegisterDump); \
     extern "C" void exception_##ec##_entry();                \
     asm(                                                     \
         ".globl exception_" #ec "_entry\n"                   \
@@ -115,9 +113,7 @@ asm(
         "    popw %es\n"                                     \
         "    popw %fs\n"                                     \
         "    popw %gs\n"                                     \
-        "    pushl %esp\n"                                   \
         "    call exception_" #ec "_handler\n"               \
-        "    add $4, %esp\n"                                 \
         "    popw %gs\n"                                     \
         "    popw %gs\n"                                     \
         "    popw %fs\n"                                     \
@@ -186,26 +182,26 @@ static void handle_crash(RegisterDump& regs, const char* description, int signal
 }
 
 EH_ENTRY_NO_CODE(6);
-void exception_6_handler(RegisterDump& regs)
+void exception_6_handler(RegisterDump regs)
 {
     handle_crash(regs, "Illegal instruction", SIGILL);
 }
 
 EH_ENTRY_NO_CODE(0);
-void exception_0_handler(RegisterDump& regs)
+void exception_0_handler(RegisterDump regs)
 {
     handle_crash(regs, "Division by zero", SIGFPE);
 }
 
 EH_ENTRY(13);
-void exception_13_handler(RegisterDump& regs)
+void exception_13_handler(RegisterDump regs)
 {
     handle_crash(regs, "General protection fault", SIGSEGV);
 }
 
 // 7: FPU not available exception
 EH_ENTRY_NO_CODE(7);
-void exception_7_handler(RegisterDump& regs)
+void exception_7_handler(RegisterDump regs)
 {
     (void)regs;
 
@@ -237,7 +233,7 @@ void exception_7_handler(RegisterDump& regs)
 
 // 14: Page Fault
 EH_ENTRY(14);
-void exception_14_handler(RegisterDump& regs)
+void exception_14_handler(RegisterDump regs)
 {
     ASSERT(current);
 
diff --git a/Kernel/Arch/i386/PIT.cpp b/Kernel/Arch/i386/PIT.cpp
index 1890dac617..b4861c3066 100644
--- a/Kernel/Arch/i386/PIT.cpp
+++ b/Kernel/Arch/i386/PIT.cpp
@@ -7,7 +7,7 @@
 #define IRQ_TIMER 0
 
 extern "C" void timer_interrupt_entry();
-extern "C" void timer_interrupt_handler(RegisterDump&);
+extern "C" void timer_interrupt_handler(RegisterDump);
 
 asm(
     ".globl timer_interrupt_entry \n"
@@ -27,9 +27,7 @@ asm(
     "    popw %es\n"
     "    popw %fs\n"
     "    popw %gs\n"
-    "    pushl %esp\n"
     "    call timer_interrupt_handler\n"
-    "    add $4, %esp\n"
     "    popw %gs\n"
     "    popw %gs\n"
     "    popw %fs\n"
@@ -42,7 +40,7 @@ asm(
 static u32 s_ticks_this_second;
 static u32 s_seconds_since_boot;
 
-void timer_interrupt_handler(RegisterDump& regs)
+void timer_interrupt_handler(RegisterDump regs)
 {
     IRQHandlerScope scope(IRQ_TIMER);
     if (++s_ticks_this_second >= TICKS_PER_SECOND) {
diff --git a/Kernel/Syscall.cpp b/Kernel/Syscall.cpp
index aa581dc9fc..a055e79510 100644
--- a/Kernel/Syscall.cpp
+++ b/Kernel/Syscall.cpp
@@ -6,7 +6,7 @@
 #include <Kernel/Scheduler.h>
 #include <Kernel/Syscall.h>
 
-extern "C" void syscall_trap_entry(RegisterDump&);
+extern "C" void syscall_trap_entry(RegisterDump);
 extern "C" void syscall_trap_handler();
 extern volatile RegisterDump* syscallRegDump;
 
@@ -28,9 +28,7 @@ asm(
     "    popw %es\n"
     "    popw %fs\n"
     "    popw %gs\n"
-    "    pushl %esp\n"
     "    call syscall_trap_entry\n"
-    "    add $4, %esp\n"
     "    popw %gs\n"
     "    popw %gs\n"
     "    popw %fs\n"
@@ -329,7 +327,7 @@ static u32 handle(RegisterDump& regs, u32 function, u32 arg1, u32 arg2, u32 arg3
 
 }
 
-void syscall_trap_entry(RegisterDump& regs)
+void syscall_trap_entry(RegisterDump regs)
 {
     current->process().big_lock().lock();
     u32 function = regs.eax;