src/cpu/x86/vm/c2_init_x86.cpp

@@ -23,10 +23,11 @@
  */
 
 #include "precompiled.hpp"
 #include "opto/compile.hpp"
 #include "opto/node.hpp"
+#include "opto/optoreg.hpp"
 
 // processor dependent initialization for i486
 
 void Compile::pd_compiler2_init() {
   guarantee(CodeEntryAlignment >= InteriorEntryAlignment, "" );

@@ -35,6 +36,26 @@
 #ifndef AMD64
   if (!VM_Version::supports_cmov()) {
     ConditionalMoveLimit = 0;
   }
 #endif // AMD64
+
+  if (UseAVX < 3) {
+    int delta = XMMRegisterImpl::max_slots_per_register * XMMRegisterImpl::number_of_registers;
+    int bottom = ConcreteRegisterImpl::max_fpr;
+    int top = bottom + delta;
+    int middle = bottom + (delta / 2);
+    int xmm_slots = XMMRegisterImpl::max_slots_per_register;
+    int lower = xmm_slots / 2;
+    // mark bad every register that we cannot get to if AVX less than 3, we have all slots in the array
+    // Note: vm2opto is allocated to ConcreteRegisterImpl::number_of_registers
+    for (int i = bottom; i < middle; i += xmm_slots) {
+      for (OptoReg::Name j = OptoReg::Name(i + lower); j<OptoReg::Name(i + xmm_slots); j = OptoReg::add(j, 1)) {
+        OptoReg::invalidate(j);
+      }
+    }
+    // mark the upper zmm bank bad and all the mask registers bad in this case
+    for (OptoReg::Name i = OptoReg::Name(middle); i<OptoReg::Name(_last_Mach_Reg - 1); i = OptoReg::add(i, 1)) {
+      OptoReg::invalidate(i);
+    }
+  }
 }