[turbofan] Add CalleeSavedFPRegisters to CallDescriptor.

src/compiler/arm64/code-generator-arm64.cc

Index: src/compiler/arm64/code-generator-arm64.cc
diff --git a/src/compiler/arm64/code-generator-arm64.cc b/src/compiler/arm64/code-generator-arm64.cc
index 8692732112708148b11c9d2824ef67ddf58f7435..fa5743ab8e4d38865959b139b880d58c9801bf08 100644
--- a/src/compiler/arm64/code-generator-arm64.cc
+++ b/src/compiler/arm64/code-generator-arm64.cc
@@ -1094,9 +1094,23 @@ void CodeGenerator::AssemblePrologue() {
     __ SetStackPointer(csp);
     __ Push(lr, fp);
     __ Mov(fp, csp);
-    // TODO(dcarney): correct callee saved registers.
-    __ PushCalleeSavedRegisters();
-    frame()->SetRegisterSaveAreaSize(20 * kPointerSize);
+
+    // Save FP registers.
+    CPURegList saves_fp = CPURegList(CPURegister::kFPRegister, kDRegSizeInBits,
+                                     descriptor->CalleeSavedFPRegisters());
+    DCHECK(saves_fp.list() == CPURegList::GetCalleeSavedFP().list());
+    int saved_count = saves_fp.Count();
+    __ PushCPURegList(saves_fp);
+    // Save registers.
+    CPURegList saves = CPURegList(CPURegister::kRegister, kXRegSizeInBits,
+                                  descriptor->CalleeSavedRegisters());
+    // TODO(palfia): TF save list is not in sync with
+    // CPURegList::GetCalleeSaved(): x30 is missing.

[jbramley, 2015/06/29 13:53:09]

x30 (lr) is caller-saved in the procedure-call standard, so we don't really need
to save it for the PCS alone. (ARM doesn't save its LR so I presume that TF
doesn't have a special need for it.) However, we do need to save an even number
of X registers here so perhaps we save it to bump us up to an even number.

[akos.palfi.imgtec, 2015/06/30 12:31:49]

Acknowledged.

+    // DCHECK(saves.list() == CPURegList::GetCalleeSaved().list());
+    saved_count += saves.Count();
+    __ PushCPURegList(saves);
+
+    frame()->SetRegisterSaveAreaSize(saved_count * kPointerSize);
   } else if (descriptor->IsJSFunctionCall()) {
     CompilationInfo* info = this->info();
     __ SetStackPointer(jssp);
@@ -1145,10 +1159,18 @@ void CodeGenerator::AssembleReturn() {
       if (stack_slots > 0) {
         __ Add(csp, csp, AlignedStackSlots(stack_slots) * kPointerSize);
       }
+
       // Restore registers.
-      // TODO(dcarney): correct callee saved registers.
-      __ PopCalleeSavedRegisters();
+      CPURegList saves = CPURegList(CPURegister::kRegister, kXRegSizeInBits,
+                                    descriptor->CalleeSavedRegisters());
+      __ PopCPURegList(saves);
+
+      CPURegList saves_fp =
+          CPURegList(CPURegister::kFPRegister, kDRegSizeInBits,
+                     descriptor->CalleeSavedFPRegisters());
+      __ PopCPURegList(saves_fp);
     }
+
     __ Mov(csp, fp);
     __ Pop(fp, lr);
     __ Ret();