X87: fix the Sqrt issue.

src/x87/lithium-codegen-x87.cc

Index: src/x87/lithium-codegen-x87.cc
diff --git a/src/x87/lithium-codegen-x87.cc b/src/x87/lithium-codegen-x87.cc
index 8f17258867182ebfacf84b7156be7e4db9a8f63f..86cc2f04d5100eb41a0771f033f8dfe190e21509 100644
--- a/src/x87/lithium-codegen-x87.cc
+++ b/src/x87/lithium-codegen-x87.cc
@@ -4021,12 +4021,65 @@ void LCodeGen::DoMathFround(LMathFround* instr) {
 
 
 void LCodeGen::DoMathSqrt(LMathSqrt* instr) {
-  X87Register input_reg = ToX87Register(instr->value());
-  X87Register output_reg = ToX87Register(instr->result());
-  DCHECK(output_reg.is(input_reg));
-  USE(output_reg);
-  X87Fxch(input_reg);
-  __ fsqrt();
+  X87Register input = ToX87Register(instr->value());
+  X87Register result_reg = ToX87Register(instr->result());
+  Register temp_result = ToRegister(instr->temp1());
+  Register temp = ToRegister(instr->temp2());
+  Label slow, done, smi, finish;
+  DCHECK(result_reg.is(input));
+
+  // Store input into Heap number and call runtime function kMathExpRT.
+  if (FLAG_inline_new) {
+    __ AllocateHeapNumber(temp_result, temp, no_reg, &slow);
+    __ jmp(&done, Label::kNear);
+  }
+
+  // Slow case: Call the runtime system to do the number allocation.
+  __ bind(&slow);
+  {
+    // TODO(3095996): Put a valid pointer value in the stack slot where the
+    // result register is stored, as this register is in the pointer map, but
+    // contains an integer value.
+    __ Move(temp_result, Immediate(0));
+
+    // Preserve the value of all registers.
+    PushSafepointRegistersScope scope(this);
+
+    __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
+    __ CallRuntimeSaveDoubles(Runtime::kAllocateHeapNumber);
+    RecordSafepointWithRegisters(
+       instr->pointer_map(), 0, Safepoint::kNoLazyDeopt);
+    __ StoreToSafepointRegisterSlot(temp_result, eax);
+  }
+  __ bind(&done);
+  X87LoadForUsage(input);
+  __ fstp_d(FieldOperand(temp_result, HeapNumber::kValueOffset));
+
+  {
+    // Preserve the value of all registers.
+    PushSafepointRegistersScope scope(this);
+
+    __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
+    __ push(temp_result);
+    __ CallRuntimeSaveDoubles(Runtime::kMathSqrtRT);
+    RecordSafepointWithRegisters(
+        instr->pointer_map(), 0, Safepoint::kNoLazyDeopt);
+    __ StoreToSafepointRegisterSlot(temp_result, eax);
+  }
+  X87PrepareToWrite(result_reg);
+  // return value of MathSqrtRT is Smi or Heap Number.
+  __ JumpIfSmi(temp_result, &smi);
+  // Heap number(double)
+  __ fld_d(FieldOperand(temp_result, HeapNumber::kValueOffset));
+  __ jmp(&finish);
+  // SMI
+  __ bind(&smi);
+  __ SmiUntag(temp_result);
+  __ push(temp_result);
+  __ fild_s(MemOperand(esp, 0));
+  __ pop(temp_result);
+  __ bind(&finish);
+  X87CommitWrite(result_reg);
 }