MIPS: Avoid HeapObject check in HStoreNamedField.

Port r21509 (78a54b0)

Original commit message:
This way an HStoreNamedField instruction can never deoptimize
itself, which is another important step towards a working
store elimination.

BUG=
R=plind44@gmail.com

Review URL: https://codereview.chromium.org/297143007

Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21525 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index f1deb38..69e36f8 100644 (file)
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -4056,23 +4056,12 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
     return;
   }
 
-  SmiCheck check_needed =
-      instr->hydrogen()->value()->IsHeapObject()
-          ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
+  __ AssertNotSmi(object);
 
-  ASSERT(!(representation.IsSmi() &&
-           instr->value()->IsConstantOperand() &&
-           !IsSmi(LConstantOperand::cast(instr->value()))));
-  if (representation.IsHeapObject()) {
-    Register value = ToRegister(instr->value());
-    if (!instr->hydrogen()->value()->type().IsHeapObject()) {
-      __ SmiTst(value, scratch);
-      DeoptimizeIf(eq, instr->environment(), scratch, Operand(zero_reg));
-
-      // We know now that value is not a smi, so we can omit the check below.
-      check_needed = OMIT_SMI_CHECK;
-    }
-  } else if (representation.IsDouble()) {
+  ASSERT(!representation.IsSmi() ||
+         !instr->value()->IsConstantOperand() ||
+         IsSmi(LConstantOperand::cast(instr->value())));
+  if (representation.IsDouble()) {
     ASSERT(access.IsInobject());
     ASSERT(!instr->hydrogen()->has_transition());
     ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
@@ -4114,7 +4103,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
                           GetRAState(),
                           kSaveFPRegs,
                           EMIT_REMEMBERED_SET,
-                          check_needed);
+                          instr->hydrogen()->SmiCheckForWriteBarrier());
     }
   } else {
     __ lw(scratch, FieldMemOperand(object, JSObject::kPropertiesOffset));
@@ -4130,7 +4119,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
                           GetRAState(),
                           kSaveFPRegs,
                           EMIT_REMEMBERED_SET,
-                          check_needed);
+                          instr->hydrogen()->SmiCheckForWriteBarrier());
     }
   }
 }

diff --git a/src/mips/lithium-mips.cc b/src/mips/lithium-mips.cc
index 562c88d..30fe8c4 100644 (file)
--- a/src/mips/lithium-mips.cc
+++ b/src/mips/lithium-mips.cc
@@ -2267,13 +2267,7 @@ LInstruction* LChunkBuilder::DoStoreNamedField(HStoreNamedField* instr) {
   // We need a temporary register for write barrier of the map field.
   LOperand* temp = needs_write_barrier_for_map ? TempRegister() : NULL;
 
-  LInstruction* result = new(zone()) LStoreNamedField(obj, val, temp);
-  if (!instr->access().IsExternalMemory() &&
-      instr->field_representation().IsHeapObject() &&
-      !instr->value()->type().IsHeapObject()) {
-    result = AssignEnvironment(result);
-  }
-  return result;
+  return new(zone()) LStoreNamedField(obj, val, temp);
 }
 
 

diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc
index 02d798c..d2fa8de 100644 (file)
--- a/src/mips/macro-assembler-mips.cc
+++ b/src/mips/macro-assembler-mips.cc
@@ -56,6 +56,11 @@ void MacroAssembler::Store(Register src,
   } else if (r.IsInteger16() || r.IsUInteger16()) {
     sh(src, dst);
   } else {
+    if (r.IsHeapObject()) {
+      AssertNotSmi(src);
+    } else if (r.IsSmi()) {
+      AssertSmi(src);
+    }
     sw(src, dst);
   }
 }