A64 support for DoubleToIStub (truncating).

src/a64/assembler-a64.cc

Index: src/a64/assembler-a64.cc
diff --git a/src/a64/assembler-a64.cc b/src/a64/assembler-a64.cc
index c06fbe900bf19cd8b57cdfbdd68039d541d68aee..81d5f015caae58ea74a003d6da2a5e0a0ac25b25 100644
--- a/src/a64/assembler-a64.cc
+++ b/src/a64/assembler-a64.cc
@@ -180,6 +180,27 @@ void RelocInfo::PatchCodeWithCall(Address target, int guard_bytes) {
 }
 
 
+Register GetRegisterThatIsNotOneOf(Register reg1, Register reg2,

[jbramley, 2014/02/13 14:20:14]

I'd call it GetAllocatableRegisterThatIsNotOneOf(...).

[rmcilroy, 2014/02/14 12:45:07]

Done.

+                                   Register reg3, Register reg4,
+                                   Register reg5, Register reg6) {
+  RegList regs = 0;
+  if (reg1.IsValid()) regs |= reg1.Bit();
+  if (reg2.IsValid()) regs |= reg2.Bit();
+  if (reg3.IsValid()) regs |= reg3.Bit();
+  if (reg4.IsValid()) regs |= reg4.Bit();
+  if (reg5.IsValid()) regs |= reg5.Bit();
+  if (reg6.IsValid()) regs |= reg6.Bit();

[jbramley, 2014/02/13 14:20:14]

CPURegList can do a lot of this for you:

CPURegList regs(reg1, reg2, ...);

for (...) {
  if (regs.IncludesAliasOf(candidate)) continue;
}

[rmcilroy, 2014/02/14 12:45:07]

Done.

+
+  for (int i = 0; i < Register::NumAllocatableRegisters(); i++) {
+    Register candidate = Register::FromAllocationIndex(i);
+    if (regs & candidate.Bit()) continue;
+    return candidate;
+  }
+  UNREACHABLE();
+  return NoReg;
+}
+
+
 bool AreAliased(const CPURegister& reg1, const CPURegister& reg2,
                 const CPURegister& reg3, const CPURegister& reg4,
                 const CPURegister& reg5, const CPURegister& reg6,