ppc: [liftoff] implement a few Load functions

Change-Id: Ia709a1c578d05d722690c57ae44019bda4eb8d5d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2918213
Auto-Submit: Junliang Yan <junyan@redhat.com>
Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/master@{#74768}

src/codegen/ppc/assembler-ppc.cc

@@ -226,6 +226,9 @@ MemOperand::MemOperand(Register rn, int32_t offset)
 MemOperand::MemOperand(Register ra, Register rb)
     : ra_(ra), offset_(0), rb_(rb) {}
 
+MemOperand::MemOperand(Register ra, Register rb, int32_t offset)
+    : ra_(ra), offset_(offset), rb_(rb) {}
+
 void Assembler::AllocateAndInstallRequestedHeapObjects(Isolate* isolate) {
   DCHECK_IMPLIES(isolate == nullptr, heap_object_requests_.empty());
   for (auto& request : heap_object_requests_) {

src/codegen/ppc/assembler-ppc.h

@@ -136,6 +136,8 @@ class V8_EXPORT_PRIVATE MemOperand {
 
   explicit MemOperand(Register ra, Register rb);
 
+  explicit MemOperand(Register ra, Register rb, int32_t offset);
+
   int32_t offset() const { return offset_; }
 
   // PowerPC - base register

src/wasm/baseline/ppc/liftoff-assembler-ppc.h

@@ -185,29 +185,29 @@ void LiftoffAssembler::LoadFromInstance(Register dst, Register instance,
 void LiftoffAssembler::LoadTaggedPointerFromInstance(Register dst,
                                                      Register instance,
                                                      int offset) {
-  bailout(kUnsupportedArchitecture, "LoadTaggedPointerFromInstance");
+  LoadTaggedPointerField(dst, MemOperand(instance, offset), r0);
 }
 
 void LiftoffAssembler::SpillInstance(Register instance) {
-  bailout(kUnsupportedArchitecture, "SpillInstance");
+  StoreU64(instance, liftoff::GetInstanceOperand(), r0);
 }
 
 void LiftoffAssembler::ResetOSRTarget() {}
 
 void LiftoffAssembler::FillInstanceInto(Register dst) {
-  bailout(kUnsupportedArchitecture, "FillInstanceInto");
+  LoadU64(dst, liftoff::GetInstanceOperand(), r0);
 }
 
 void LiftoffAssembler::LoadTaggedPointer(Register dst, Register src_addr,
                                          Register offset_reg,
                                          int32_t offset_imm,
                                          LiftoffRegList pinned) {
-  bailout(kUnsupportedArchitecture, "LoadTaggedPointer");
+  LoadTaggedPointerField(dst, MemOperand(src_addr, offset_reg, offset_imm), r0);
 }
 
 void LiftoffAssembler::LoadFullPointer(Register dst, Register src_addr,
                                        int32_t offset_imm) {
-  bailout(kUnsupportedArchitecture, "LoadFullPointer");
+  LoadU64(dst, MemOperand(src_addr, offset_imm), r0);
 }
 
 void LiftoffAssembler::StoreTaggedPointer(Register dst_addr,