X86: Fix argument register indexing.

Code was assuming that all argument registers followed in order from ArgumentReg0. There is now an ArgumentReg array which is indexed to find the right index. There is a constant, NumArgumentRegs, which can be used to protect against using an invalid ArgumentReg.

--HG--
extra : convert_revision : f448a3ca4d6adc3fc3323562870f70eec05a8a1f

1 files changed, 8 insertions, 2 deletions

diff --git a/src/cpu/ozone/cpu.hh b/src/cpu/ozone/cpu.hh
index 2432df55e..92b00af26 100644
--- a/src/cpu/ozone/cpu.hh
+++ b/src/cpu/ozone/cpu.hh
@@ -253,11 +253,17 @@ class OzoneCPU : public BaseCPU
 
 #if !FULL_SYSTEM
         TheISA::IntReg getSyscallArg(int i)
-        { return thread->renameTable[TheISA::ArgumentReg0 + i]->readIntResult(); }
+        {
+            assert(i < TheISA::NumArgumentRegs);
+            return thread->renameTable[TheISA::ArgumentReg[i]]->readIntResult();
+        }
 
         // used to shift args for indirect syscall
         void setSyscallArg(int i, TheISA::IntReg val)
-        { thread->renameTable[TheISA::ArgumentReg0 + i]->setIntResult(i); }
+        {
+            assert(i < TheISA::NumArgumentRegs);
+            thread->renameTable[TheISA::ArgumentReg[i]]->setIntResult(i);
+        }
 
         void setSyscallReturn(SyscallReturn return_value)
         { cpu->setSyscallReturn(return_value, thread->readTid()); }