Debug: Implement getArgument() and function skipping for ARM.

In the process make add skipFuction() to handle isa specific function skipping
instead of ifdefs and other ugliness. For almost all ABIs, 64 bit arguments can
only start in even registers.  Size is now passed to getArgument() so that 32
bit systems can make decisions about register selection for 64 bit arguments.
The number argument is now passed by reference because getArgument() will need
to change it based on the size of the argument and the current argument number.

For ARM, if the argument number is odd and a 64-bit register is requested the
number must first be incremented to because all 64 bit arguments are passed
in an even argument register. Then the number will be incremented again to
access both halves of the argument.

2 files changed, 11 insertions, 2 deletions

diff --git a/src/arch/x86/utility.cc b/src/arch/x86/utility.cc
index 50574bcde..d74bb74b6 100644
--- a/src/arch/x86/utility.cc
+++ b/src/arch/x86/utility.cc
@@ -52,7 +52,7 @@
 
 namespace X86ISA {
 
-uint64_t getArgument(ThreadContext *tc, int number, bool fp) {
+uint64_t getArgument(ThreadContext *tc, int &number, uint8_t size, bool fp) {
 #if FULL_SYSTEM
     panic("getArgument() not implemented for x86!\n");
 #else
@@ -233,4 +233,11 @@ copyRegs(ThreadContext *src, ThreadContext *dest)
     dest->setNextPC(src->readNextPC());
 }
 
+void
+skipFunction(ThreadContext *tc)
+{
+    panic("Not implemented for x86\n");
+}
+
+
 } //namespace X86_ISA
diff --git a/src/arch/x86/utility.hh b/src/arch/x86/utility.hh
index bfa102529..fd9ac59fd 100644
--- a/src/arch/x86/utility.hh
+++ b/src/arch/x86/utility.hh
@@ -52,7 +52,7 @@ class ThreadContext;
 
 namespace X86ISA
 {
-    uint64_t getArgument(ThreadContext *tc, int number, bool fp);
+    uint64_t getArgument(ThreadContext *tc, int &number, uint8_t size, bool fp);
 
     static inline bool
     inUserMode(ThreadContext *tc)
@@ -83,6 +83,8 @@ namespace X86ISA
     void copyRegs(ThreadContext *src, ThreadContext *dest);
 
     void copyMiscRegs(ThreadContext *src, ThreadContext *dest);
+
+    void skipFunction(ThreadContext *tc);
 };
 
 #endif // __ARCH_X86_UTILITY_HH__