codegen: Avoid some uses of PointerType::getElementType() (#43721)

getElementType() will eventually go away with the LLVM switch
to opaque pointers.

The assertion in gen_cfun_wrapper is still checked within
CreateAlignedLoad.

src/ccall.cpp

@@ -271,7 +271,7 @@ static Value *emit_plt(
  functype, attrs, cc, f_lib, f_name, libptrgv, llvmgv, runtime_lib);
  }
  GlobalVariable *got = prepare_global_in(jl_Module, sharedgot);
- LoadInst *got_val = ctx.builder.CreateAlignedLoad(got->getType()->getElementType(), got, Align(sizeof(void*)));
+ LoadInst *got_val = ctx.builder.CreateAlignedLoad(got->getValueType(), got, Align(sizeof(void*)));
  // See comment in `runtime_sym_lookup` above. This in principle needs a
  // consume ordering too. This is even less likely to cause issues though
  // since the only thing we do to this loaded pointer is to call it

src/cgutils.cpp

@@ -2482,30 +2482,29 @@ static Value *emit_arraylen(jl_codectx_t &ctx, const jl_cgval_t &tinfo)
 
 static Value *emit_arrayptr_internal(jl_codectx_t &ctx, const jl_cgval_t &tinfo, Value *t, unsigned AS, bool isboxed)
 {
- Value *addr =
- ctx.builder.CreateStructGEP(jl_array_llvmt,
- emit_bitcast(ctx, t, jl_parray_llvmt),
- 0); // index (not offset) of data field in jl_parray_llvmt
+ Value *addr = ctx.builder.CreateStructGEP(jl_array_llvmt,
+ emit_bitcast(ctx, t, jl_parray_llvmt), 0);
  // Normally allocated array of 0 dimension always have a inline pointer.
  // However, we can't rely on that here since arrays can also be constructed from C pointers.
- MDNode *tbaa = arraytype_constshape(tinfo.typ) ? tbaa_const : tbaa_arrayptr;
  PointerType *PT = cast<PointerType>(addr->getType());
- PointerType *PPT = cast<PointerType>(PT->getElementType());
+ PointerType *PPT = cast<PointerType>(jl_array_llvmt->getElementType(0));
+ PointerType *LoadT = PPT;
+
  if (isboxed) {
- addr = ctx.builder.CreateBitCast(addr,
-  PointerType::get(PointerType::get(T_prjlvalue, AS),
-  PT->getAddressSpace()));
- } else if (AS != PPT->getAddressSpace()) {
-  addr = ctx.builder.CreateBitCast(addr,
-  PointerType::get(
-  PointerType::get(PPT->getElementType(), AS),
-  PT->getAddressSpace()));
- }
- LoadInst *LI = ctx.builder.CreateAlignedLoad(
-  cast<PointerType>(addr->getType())->getElementType(), addr, Align(sizeof(char*)));
+ LoadT = PointerType::get(T_prjlvalue, AS);
+ }
+ else if (AS != PPT->getAddressSpace()) {
+  LoadT = PointerType::getWithSamePointeeType(PPT, AS);
+ }
+ if (LoadT != PPT) {
+ const auto Ty = PointerType::get(LoadT, PT->getAddressSpace());
+ addr = ctx.builder.CreateBitCast(addr, Ty);
+ }
+
+ LoadInst *LI = ctx.builder.CreateAlignedLoad(LoadT, addr, Align(sizeof(char *)));
  LI->setOrdering(AtomicOrdering::NotAtomic);
  LI->setMetadata(LLVMContext::MD_nonnull, MDNode::get(jl_LLVMContext, None));
- tbaa_decorate(tbaa, LI);
+ tbaa_decorate(arraytype_constshape(tinfo.typ) ? tbaa_const : tbaa_arrayptr, LI);
  return LI;
 }
 

src/codegen.cpp

@@ -159,7 +159,7 @@ static Type *T_pjlvalue;
 static Type *T_prjlvalue;
 static Type *T_ppjlvalue;
 static Type *T_pprjlvalue;
-static Type *jl_array_llvmt;
+static StructType *jl_array_llvmt;
 static Type *jl_parray_llvmt;
 static FunctionType *jl_func_sig;
 static FunctionType *jl_func_sig_sparams;
@@ -1143,7 +1143,7 @@ static inline GlobalVariable *prepare_global_in(Module *M, GlobalVariable *G)
  GlobalValue *local = M->getNamedValue(G->getName());
  if (!local) {
  // Copy the GlobalVariable, but without the initializer, so it becomes a declaration
- GlobalVariable *proto = new GlobalVariable(*M, G->getType()->getElementType(),
+ GlobalVariable *proto = new GlobalVariable(*M, G->getValueType(),
  G->isConstant(), GlobalVariable::ExternalLinkage,
  nullptr, G->getName(), nullptr, G->getThreadLocalMode());
  proto->copyAttributesFrom(G);
@@ -5242,7 +5242,6 @@ static Function* gen_cfun_wrapper(
  // undo whatever we might have done to this poor argument
  assert(jl_is_datatype(jargty));
  if (sig.byRefList.at(i)) {
- assert(cast<PointerType>(val->getType())->getElementType() == sig.fargt[i]);
  val = ctx.builder.CreateAlignedLoad(sig.fargt[i], val, Align(1)); // unknown alignment from C
  }
  else {
@@ -5476,7 +5475,7 @@ static Function* gen_cfun_wrapper(
  ctx.builder.ClearInsertionPoint();
 
  if (aliasname) {
- GlobalAlias::create(cw->getType()->getElementType(), cw->getType()->getAddressSpace(),
+ GlobalAlias::create(cw->getValueType(), cw->getType()->getAddressSpace(),
  GlobalValue::ExternalLinkage, aliasname, cw, M);
  }
 

src/llvm-ptls.cpp

@@ -273,7 +273,7 @@ bool LowerPTLS::runOnModule(Module &_M)
 #endif
  T_pgcstack_getter = FT_pgcstack_getter->getPointerTo();
  T_pppjlvalue = cast<PointerType>(FT_pgcstack_getter->getReturnType());
- T_ppjlvalue = cast<PointerType>(T_pppjlvalue->getElementType());
+ T_ppjlvalue = JuliaType::get_ppjlvalue_ty(*ctx);
  if (imaging_mode) {
  pgcstack_func_slot = create_aliased_global(T_pgcstack_getter, "jl_pgcstack_func_slot");
  pgcstack_key_slot = create_aliased_global(T_size, "jl_pgcstack_key_slot"); // >= sizeof(jl_pgcstack_key_t)