[mips][baseline] Remove initial relocation when compiling on heap

And fallback to handle references on heap compilation.

Port 7ac3b55a
Port 642a4673

Bug: v8:11872

Change-Id: Ia371c53d32c0f1f4496fee1a7c72461ea291191f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3066946
Auto-Submit: Liu yu <liuyu@loongson.cn>
Reviewed-by: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Commit-Queue: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Cr-Commit-Position: refs/heads/master@{#76045}

src/codegen/mips/assembler-mips.cc

@@ -3537,7 +3537,16 @@ void Assembler::RelocateRelativeReference(RelocInfo::Mode rmode, Address pc,
   }
 }
 
+void Assembler::FixOnHeapReferences() {
+  for (auto p : saved_handles_for_raw_object_ptr_) {
+    Address base = reinterpret_cast<Address>(buffer_->start() + p.first);
+    set_target_value_at(base, p.second);
+  }
+}
+
 void Assembler::GrowBuffer() {
+  bool previously_on_heap = buffer_->IsOnHeap();
+
   // Compute new buffer size.
   int old_size = buffer_->size();
   int new_size = std::min(2 * old_size, old_size + 1 * MB);
@@ -3580,6 +3589,8 @@ void Assembler::GrowBuffer() {
       RelocateInternalReference(rmode, it.rinfo()->pc(), pc_delta);
     }
   }
+  // Patch on-heap references to handles.
+  if (previously_on_heap && !buffer_->IsOnHeap()) FixOnHeapReferences();
   DCHECK(!overflow());
 }
 

src/codegen/mips/assembler-mips.h

@@ -167,6 +167,8 @@ class V8_EXPORT_PRIVATE Assembler : public AssemblerBase {
     GetCode(isolate, desc, kNoSafepointTable, kNoHandlerTable);
   }
 
+  void FixOnHeapReferences();
+
   // Unused on this architecture.
   void MaybeEmitOutOfLineConstantPool() {}
 

src/codegen/mips/macro-assembler-mips.cc

@@ -1394,6 +1394,15 @@ void TurboAssembler::li(Register rd, Operand j, LiFlags mode) {
         ori(rd, rd, (j.immediate() & kImm16Mask));
       }
     }
+  } else if (IsOnHeap() && RelocInfo::IsEmbeddedObjectMode(j.rmode())) {
+    BlockGrowBufferScope block_growbuffer(this);
+    saved_handles_for_raw_object_ptr_.push_back(
+        std::make_pair(pc_offset(), j.immediate()));
+    Handle<HeapObject> handle(reinterpret_cast<Address*>(j.immediate()));
+    int32_t immediate = handle->ptr();
+    RecordRelocInfo(j.rmode(), immediate);
+    lui(rd, (immediate >> kLuiShift) & kImm16Mask);
+    ori(rd, rd, (immediate & kImm16Mask));
   } else {
     int32_t immediate;
     if (j.IsHeapObjectRequest()) {

src/codegen/mips64/assembler-mips64.cc

@@ -3736,7 +3736,16 @@ int Assembler::RelocateInternalReference(RelocInfo::Mode rmode, Address pc,
   }
 }
 
+void Assembler::FixOnHeapReferences() {
+  for (auto p : saved_handles_for_raw_object_ptr_) {
+    Address base = reinterpret_cast<Address>(buffer_->start() + p.first);
+    set_target_value_at(base, p.second);
+  }
+}
+
 void Assembler::GrowBuffer() {
+  bool previously_on_heap = buffer_->IsOnHeap();
+
   // Compute new buffer size.
   int old_size = buffer_->size();
   int new_size = std::min(2 * old_size, old_size + 1 * MB);
@@ -3778,6 +3787,8 @@ void Assembler::GrowBuffer() {
       RelocateInternalReference(rmode, it.rinfo()->pc(), pc_delta);
     }
   }
+  // Patch on-heap references to handles.
+  if (previously_on_heap && !buffer_->IsOnHeap()) FixOnHeapReferences();
   DCHECK(!overflow());
 }
 

src/codegen/mips64/assembler-mips64.h

@@ -167,6 +167,8 @@ class V8_EXPORT_PRIVATE Assembler : public AssemblerBase {
     GetCode(isolate, desc, kNoSafepointTable, kNoHandlerTable);
   }
 
+  void FixOnHeapReferences();
+
   // Unused on this architecture.
   void MaybeEmitOutOfLineConstantPool() {}
 

src/codegen/mips64/macro-assembler-mips64.cc

@@ -1914,6 +1914,17 @@ void TurboAssembler::li(Register rd, Operand j, LiFlags mode) {
     } else {
       li_optimized(rd, j, mode);
     }
+  } else if (IsOnHeap() && RelocInfo::IsEmbeddedObjectMode(j.rmode())) {
+    BlockGrowBufferScope block_growbuffer(this);
+    saved_handles_for_raw_object_ptr_.push_back(
+        std::make_pair(pc_offset(), j.immediate()));
+    Handle<HeapObject> handle(reinterpret_cast<Address*>(j.immediate()));
+    int64_t immediate = handle->ptr();
+    RecordRelocInfo(j.rmode(), immediate);
+    lui(rd, (immediate >> 32) & kImm16Mask);
+    ori(rd, rd, (immediate >> 16) & kImm16Mask);
+    dsll(rd, rd, 16);
+    ori(rd, rd, immediate & kImm16Mask);
   } else if (MustUseReg(j.rmode())) {
     int64_t immediate;
     if (j.IsHeapObjectRequest()) {