S390: [turbofan] Prevent storing signalling NaNs into holey double arrays.

Port 6470ddad

Original commit message:

    This introduces SilenceNaN operator, which makes sure that we only
    store quiet NaNs into holey arrays. We omit the NaN silencing code
    at instruction selection time if the input is an operation that
    cannot possibly produce signalling NaNs.

R=jarin@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com, bjaideep@ca.ibm.com

BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2070583002
Cr-Commit-Position: refs/heads/master@{#37012}

src/compiler/s390/code-generator-s390.cc

@@ -396,7 +396,6 @@ Condition FlagsConditionToCondition(FlagsCondition condition, ArchOpcode op) {
                      0, 1);                                                    \
     /* Move the result in the double result register. */                       \
     __ MovFromFloatResult(i.OutputDoubleRegister());                           \
-    DCHECK_EQ(LeaveRC, i.OutputRCBit());                                       \
   } while (0)
 
 #define ASSEMBLE_IEEE754_BINOP(name)                                           \
@@ -411,7 +410,6 @@ Condition FlagsConditionToCondition(FlagsCondition condition, ArchOpcode op) {
                      0, 2);                                                    \
     /* Move the result in the double result register. */                       \
     __ MovFromFloatResult(i.OutputDoubleRegister());                           \
-    DCHECK_EQ(LeaveRC, i.OutputRCBit());                                       \
   } while (0)
 
 #define ASSEMBLE_FLOAT_MAX(double_scratch_reg, general_scratch_reg) \
@@ -1345,6 +1343,12 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       }
       break;
 #endif
+    case kS390_Float64SilenceNaN: {
+      DoubleRegister value = i.InputDoubleRegister(0);
+      DoubleRegister result = i.OutputDoubleRegister();
+      __ CanonicalizeNaN(result, value);
+      break;
+    }
     case kS390_Push:
       if (instr->InputAt(0)->IsFPRegister()) {
         __ lay(sp, MemOperand(sp, -kDoubleSize));

src/compiler/s390/instruction-codes-s390.h

@@ -107,6 +107,7 @@ namespace compiler {
   V(S390_Float32ToInt32)           \
   V(S390_Float32ToUint32)          \
   V(S390_Float32ToDouble)          \
+  V(S390_Float64SilenceNaN)        \
   V(S390_DoubleToInt32)            \
   V(S390_DoubleToUint32)           \
   V(S390_DoubleToInt64)            \

src/compiler/s390/instruction-scheduler-s390.cc

@@ -104,6 +104,7 @@ int InstructionScheduler::GetTargetInstructionFlags(
     case kS390_Float32ToUint32:
     case kS390_Float32ToUint64:
     case kS390_Float32ToDouble:
+    case kS390_Float64SilenceNaN:
     case kS390_DoubleToInt32:
     case kS390_DoubleToUint32:
     case kS390_Float32ToInt64:

src/compiler/s390/instruction-selector-s390.cc

@@ -1179,6 +1179,10 @@ void InstructionSelector::VisitFloat32Max(Node* node) { UNREACHABLE(); }
 
 void InstructionSelector::VisitFloat64Max(Node* node) { UNREACHABLE(); }
 
+void InstructionSelector::VisitFloat64SilenceNaN(Node* node) {
+  VisitRR(this, kS390_Float64SilenceNaN, node);
+}
+
 void InstructionSelector::VisitFloat32Min(Node* node) { UNREACHABLE(); }
 
 void InstructionSelector::VisitFloat64Min(Node* node) { UNREACHABLE(); }