/// ValidateRegisterVariable - Check that a static "asm" variable is
/// well-formed. If not, emit error messages and return true. If so, return
/// false.
bool ValidateRegisterVariable(tree decl) {
const char *Name = IDENTIFIER_POINTER(DECL_ASSEMBLER_NAME(decl));
int RegNumber = decode_reg_name(Name);
const Type *Ty = ConvertType(TREE_TYPE(decl));
// If this has already been processed, don't emit duplicate error messages.
if (DECL_LLVM_SET_P(decl)) {
// Error state encoded into DECL_LLVM.
return cast<ConstantInt>(DECL_LLVM(decl))->getZExtValue();
}
/* Detect errors in declaring global registers. */
if (RegNumber == -1)
error("%Jregister name not specified for %qD", decl, decl);
else if (RegNumber < 0)
error("%Jinvalid register name for %qD", decl, decl);
else if (TYPE_MODE(TREE_TYPE(decl)) == BLKmode)
error("%Jdata type of %qD isn%'t suitable for a register", decl, decl);
#if 0 // FIXME: enable this.
else if (!HARD_REGNO_MODE_OK(RegNumber, TYPE_MODE(TREE_TYPE(decl))))
error("%Jregister specified for %qD isn%'t suitable for data type",
decl, decl);
#endif
else if (DECL_INITIAL(decl) != 0 && TREE_STATIC(decl))
error("global register variable has initial value");
else if (!Ty->isFirstClassType())
sorry("%JLLVM cannot handle register variable %qD, report a bug",
decl, decl);
else {
if (TREE_THIS_VOLATILE(decl))
warning("volatile register variables don%'t work as you might wish");
SET_DECL_LLVM(decl, ConstantInt::getFalse());
return false; // Everything ok.
}
SET_DECL_LLVM(decl, ConstantInt::getTrue());
return true;
}
void
use_thunk (tree thunk_fndecl, bool emit_p)
{
tree a, t, function, alias;
tree virtual_offset;
HOST_WIDE_INT fixed_offset, virtual_value;
bool this_adjusting = DECL_THIS_THUNK_P (thunk_fndecl);
/* We should have called finish_thunk to give it a name. */
gcc_assert (DECL_NAME (thunk_fndecl));
/* We should never be using an alias, always refer to the
aliased thunk. */
gcc_assert (!THUNK_ALIAS (thunk_fndecl));
if (TREE_ASM_WRITTEN (thunk_fndecl))
return;
function = THUNK_TARGET (thunk_fndecl);
if (DECL_RESULT (thunk_fndecl))
/* We already turned this thunk into an ordinary function.
There's no need to process this thunk again. */
return;
if (DECL_THUNK_P (function))
/* The target is itself a thunk, process it now. */
use_thunk (function, emit_p);
/* Thunks are always addressable; they only appear in vtables. */
TREE_ADDRESSABLE (thunk_fndecl) = 1;
/* Figure out what function is being thunked to. It's referenced in
this translation unit. */
TREE_ADDRESSABLE (function) = 1;
mark_used (function);
if (!emit_p)
return;
if (TARGET_USE_LOCAL_THUNK_ALIAS_P (function))
alias = make_alias_for_thunk (function);
else
alias = function;
fixed_offset = THUNK_FIXED_OFFSET (thunk_fndecl);
virtual_offset = THUNK_VIRTUAL_OFFSET (thunk_fndecl);
if (virtual_offset)
{
if (!this_adjusting)
virtual_offset = BINFO_VPTR_FIELD (virtual_offset);
virtual_value = tree_low_cst (virtual_offset, /*pos=*/0);
gcc_assert (virtual_value);
}
else
virtual_value = 0;
/* And, if we need to emit the thunk, it's used. */
mark_used (thunk_fndecl);
/* This thunk is actually defined. */
DECL_EXTERNAL (thunk_fndecl) = 0;
/* The linkage of the function may have changed. FIXME in linkage
rewrite. */
TREE_PUBLIC (thunk_fndecl) = TREE_PUBLIC (function);
DECL_VISIBILITY (thunk_fndecl) = DECL_VISIBILITY (function);
DECL_VISIBILITY_SPECIFIED (thunk_fndecl)
= DECL_VISIBILITY_SPECIFIED (function);
if (DECL_ONE_ONLY (function))
make_decl_one_only (thunk_fndecl);
if (flag_syntax_only)
{
TREE_ASM_WRITTEN (thunk_fndecl) = 1;
return;
}
push_to_top_level ();
if (TARGET_USE_LOCAL_THUNK_ALIAS_P (function)
/* LLVM LOCAL begin */
/* PR1085 */
#ifdef ENABLE_LLVM
&& 0
#endif
/* LLVM LOCAL end */
&& targetm.have_named_sections)
{
resolve_unique_section (function, 0, flag_function_sections);
if (DECL_SECTION_NAME (function) != NULL && DECL_ONE_ONLY (function))
{
resolve_unique_section (thunk_fndecl, 0, flag_function_sections);
/* Output the thunk into the same section as function. */
DECL_SECTION_NAME (thunk_fndecl) = DECL_SECTION_NAME (function);
}
}
/* APPLE LOCAL begin mainline 2006-12-02 5128086 */ \
/* Set up cloned argument trees for the thunk. */
t = NULL_TREE;
for (a = DECL_ARGUMENTS (function); a; a = TREE_CHAIN (a))
{
tree x = copy_node (a);
TREE_CHAIN (x) = t;
DECL_CONTEXT (x) = thunk_fndecl;
/* LLVM LOCAL begin */
#ifndef ENABLE_LLVM
SET_DECL_RTL (x, NULL_RTX);
#else
SET_DECL_LLVM (x, 0);
#endif
/* LLVM LOCAL end */
DECL_HAS_VALUE_EXPR_P (x) = 0;
t = x;
}
a = nreverse (t);
DECL_ARGUMENTS (thunk_fndecl) = a;
if (this_adjusting
/* LLVM LOCAL begin */
#ifdef ENABLE_LLVM
&& 0 /* FIXME: Always use a thunk function */
#endif
/* LLVM LOCAL end */
&& targetm.asm_out.can_output_mi_thunk (thunk_fndecl, fixed_offset,
virtual_value, alias))
{
const char *fnname;
tree fn_block;
current_function_decl = thunk_fndecl;
DECL_RESULT (thunk_fndecl)
= build_decl (RESULT_DECL, 0, integer_type_node);
fnname = XSTR (XEXP (DECL_RTL (thunk_fndecl), 0), 0);
/* The back-end expects DECL_INITIAL to contain a BLOCK, so we
create one. */
fn_block = make_node (BLOCK);
BLOCK_VARS (fn_block) = a;
DECL_INITIAL (thunk_fndecl) = fn_block;
/* APPLE LOCAL end mainline 2006-12-02 5128086 */ \
init_function_start (thunk_fndecl);
current_function_is_thunk = 1;
assemble_start_function (thunk_fndecl, fnname);
targetm.asm_out.output_mi_thunk (asm_out_file, thunk_fndecl,
fixed_offset, virtual_value, alias);
assemble_end_function (thunk_fndecl, fnname);
init_insn_lengths ();
current_function_decl = 0;
cfun = 0;
TREE_ASM_WRITTEN (thunk_fndecl) = 1;
}
else
{
/* If this is a covariant thunk, or we don't have the necessary
code for efficient thunks, generate a thunk function that
just makes a call to the real function. Unfortunately, this
doesn't work for varargs. */
if (varargs_function_p (function))
error ("generic thunk code fails for method %q#D which uses %<...%>",
function);
DECL_RESULT (thunk_fndecl) = NULL_TREE;
start_preparsed_function (thunk_fndecl, NULL_TREE, SF_PRE_PARSED);
/* We don't bother with a body block for thunks. */
/* There's no need to check accessibility inside the thunk body. */
push_deferring_access_checks (dk_no_check);
t = a;
if (this_adjusting)
t = thunk_adjust (t, /*this_adjusting=*/1,
fixed_offset, virtual_offset);
/* Build up the call to the real function. */
t = tree_cons (NULL_TREE, t, NULL_TREE);
for (a = TREE_CHAIN (a); a; a = TREE_CHAIN (a))
t = tree_cons (NULL_TREE, a, t);
t = nreverse (t);
t = build_call (alias, t);
CALL_FROM_THUNK_P (t) = 1;
if (VOID_TYPE_P (TREE_TYPE (t)))
finish_expr_stmt (t);
else
{
if (!this_adjusting)
{
tree cond = NULL_TREE;
if (TREE_CODE (TREE_TYPE (t)) == POINTER_TYPE)
{
/* If the return type is a pointer, we need to
protect against NULL. We know there will be an
adjustment, because that's why we're emitting a
thunk. */
t = save_expr (t);
cond = cp_convert (boolean_type_node, t);
}
t = thunk_adjust (t, /*this_adjusting=*/0,
fixed_offset, virtual_offset);
if (cond)
t = build3 (COND_EXPR, TREE_TYPE (t), cond, t,
cp_convert (TREE_TYPE (t), integer_zero_node));
}
if (IS_AGGR_TYPE (TREE_TYPE (t)))
t = build_cplus_new (TREE_TYPE (t), t);
finish_return_stmt (t);
}
/* Since we want to emit the thunk, we explicitly mark its name as
referenced. */
mark_decl_referenced (thunk_fndecl);
/* But we don't want debugging information about it. */
DECL_IGNORED_P (thunk_fndecl) = 1;
/* Re-enable access control. */
pop_deferring_access_checks ();
thunk_fndecl = finish_function (0);
tree_lowering_passes (thunk_fndecl);
expand_body (thunk_fndecl);
}
pop_from_top_level ();
}
// make_decl_llvm - Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL
// should have static storage duration. In other words, it should not be an
// automatic variable, including PARM_DECLs.
//
// There is, however, one exception: this function handles variables explicitly
// placed in a particular register by the user.
//
// This function corresponds to make_decl_rtl in varasm.c, and is implicitly
// called by DECL_LLVM if a decl doesn't have an LLVM set.
//
void make_decl_llvm(tree decl) {
#ifdef ENABLE_CHECKING
// Check that we are not being given an automatic variable.
// A weak alias has TREE_PUBLIC set but not the other bits.
if (TREE_CODE(decl) == PARM_DECL || TREE_CODE(decl) == RESULT_DECL
|| (TREE_CODE(decl) == VAR_DECL && !TREE_STATIC(decl) &&
!TREE_PUBLIC(decl) && !DECL_EXTERNAL(decl) && !DECL_REGISTER(decl)))
abort();
// And that we were not given a type or a label. */
else if (TREE_CODE(decl) == TYPE_DECL || TREE_CODE(decl) == LABEL_DECL)
abort ();
#endif
// For a duplicate declaration, we can be called twice on the
// same DECL node. Don't discard the LLVM already made.
if (DECL_LLVM_SET_P(decl)) return;
if (errorcount || sorrycount)
return; // Do not process broken code.
// Global register variable with asm name, e.g.:
// register unsigned long esp __asm__("ebp");
if (TREE_CODE(decl) != FUNCTION_DECL && DECL_REGISTER(decl)) {
// This just verifies that the variable is ok. The actual "load/store"
// code paths handle accesses to the variable.
ValidateRegisterVariable(decl);
return;
}
timevar_push(TV_LLVM_GLOBALS);
const char *Name = "";
if (DECL_NAME(decl))
if (tree AssemblerName = DECL_ASSEMBLER_NAME(decl))
Name = IDENTIFIER_POINTER(AssemblerName);
// Now handle ordinary static variables and functions (in memory).
// Also handle vars declared register invalidly.
if (Name[0] == 1) {
#ifdef REGISTER_PREFIX
if (strlen (REGISTER_PREFIX) != 0) {
int reg_number = decode_reg_name(Name);
if (reg_number >= 0 || reg_number == -3)
error("%Jregister name given for non-register variable %qD",
decl, decl);
}
#endif
}
// Specifying a section attribute on a variable forces it into a
// non-.bss section, and thus it cannot be common.
if (TREE_CODE(decl) == VAR_DECL && DECL_SECTION_NAME(decl) != NULL_TREE &&
DECL_INITIAL(decl) == NULL_TREE && DECL_COMMON(decl))
DECL_COMMON(decl) = 0;
// Variables can't be both common and weak.
if (TREE_CODE(decl) == VAR_DECL && DECL_WEAK(decl))
DECL_COMMON(decl) = 0;
// Okay, now we need to create an LLVM global variable or function for this
// object. Note that this is quite possibly a forward reference to the
// object, so its type may change later.
if (TREE_CODE(decl) == FUNCTION_DECL) {
assert(Name[0] && "Function with empty name!");
// If this function has already been created, reuse the decl. This happens
// when we have something like __builtin_memset and memset in the same file.
Function *FnEntry = TheModule->getFunction(Name);
if (FnEntry == 0) {
unsigned CC;
const FunctionType *Ty =
TheTypeConverter->ConvertFunctionType(TREE_TYPE(decl), decl, NULL, CC);
FnEntry = new Function(Ty, Function::ExternalLinkage, Name, TheModule);
FnEntry->setCallingConv(CC);
// Check for external weak linkage
if (DECL_EXTERNAL(decl) && DECL_WEAK(decl))
FnEntry->setLinkage(Function::ExternalWeakLinkage);
#ifdef TARGET_ADJUST_LLVM_LINKAGE
TARGET_ADJUST_LLVM_LINKAGE(FnEntry,decl);
#endif /* TARGET_ADJUST_LLVM_LINKAGE */
// Handle visibility style
if (TREE_PUBLIC(decl)) {
if (DECL_VISIBILITY(decl) == VISIBILITY_HIDDEN)
FnEntry->setVisibility(GlobalValue::HiddenVisibility);
else if (DECL_VISIBILITY(decl) == VISIBILITY_PROTECTED)
FnEntry->setVisibility(GlobalValue::ProtectedVisibility);
}
assert(FnEntry->getName() == Name &&"Preexisting fn with the same name!");
}
SET_DECL_LLVM(decl, FnEntry);
} else {
assert((TREE_CODE(decl) == VAR_DECL ||
TREE_CODE(decl) == CONST_DECL) && "Not a function or var decl?");
const Type *Ty = ConvertType(TREE_TYPE(decl));
GlobalVariable *GV ;
// If we have "extern void foo", make the global have type {} instead of
// type void.
if (Ty == Type::VoidTy)
Ty = StructType::get(std::vector<const Type*>(), false);
if (Name[0] == 0) { // Global has no name.
GV = new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage, 0,
"", TheModule);
// Check for external weak linkage
if (DECL_EXTERNAL(decl) && DECL_WEAK(decl))
GV->setLinkage(GlobalValue::ExternalWeakLinkage);
#ifdef TARGET_ADJUST_LLVM_LINKAGE
TARGET_ADJUST_LLVM_LINKAGE(GV,decl);
#endif /* TARGET_ADJUST_LLVM_LINKAGE */
// Handle visibility style
if (TREE_PUBLIC(decl)) {
if (DECL_VISIBILITY(decl) == VISIBILITY_HIDDEN)
GV->setVisibility(GlobalValue::HiddenVisibility);
else if (DECL_VISIBILITY(decl) == VISIBILITY_PROTECTED)
GV->setVisibility(GlobalValue::ProtectedVisibility);
}
} else {
// If the global has a name, prevent multiple vars with the same name from
// being created.
GlobalVariable *GVE = TheModule->getGlobalVariable(Name);
if (GVE == 0) {
GV = new GlobalVariable(Ty, false, GlobalValue::ExternalLinkage,0,
Name, TheModule);
// Check for external weak linkage
if (DECL_EXTERNAL(decl) && DECL_WEAK(decl))
GV->setLinkage(GlobalValue::ExternalWeakLinkage);
#ifdef TARGET_ADJUST_LLVM_LINKAGE
TARGET_ADJUST_LLVM_LINKAGE(GV,decl);
#endif /* TARGET_ADJUST_LLVM_LINKAGE */
// Handle visibility style
if (TREE_PUBLIC(decl)) {
if (DECL_VISIBILITY(decl) == VISIBILITY_HIDDEN)
GV->setVisibility(GlobalValue::HiddenVisibility);
else if (DECL_VISIBILITY(decl) == VISIBILITY_PROTECTED)
GV->setVisibility(GlobalValue::ProtectedVisibility);
}
// If GV got renamed, then there is already an object with this name in
// the symbol table. If this happens, the old one must be a forward
// decl, just replace it with a cast of the new one.
if (GV->getName() != Name) {
Function *F = TheModule->getFunction(Name);
assert(F && F->isDeclaration() && "A function turned into a global?");
// Replace any uses of "F" with uses of GV.
Value *FInNewType = ConstantExpr::getBitCast(GV, F->getType());
F->replaceAllUsesWith(FInNewType);
// Update the decl that points to F.
changeLLVMValue(F, FInNewType);
// Now we can give GV the proper name.
GV->takeName(F);
// F is now dead, nuke it.
F->eraseFromParent();
}
} else {
GV = GVE; // Global already created, reuse it.
}
}
if ((TREE_READONLY(decl) && !TREE_SIDE_EFFECTS(decl)) ||
TREE_CODE(decl) == CONST_DECL) {
if (DECL_EXTERNAL(decl)) {
// Mark external globals constant even though they could be marked
// non-constant in the defining translation unit. The definition of the
// global determines whether the global is ultimately constant or not,
// marking this constant will allow us to do some extra (legal)
// optimizations that we would otherwise not be able to do. (In C++,
// any global that is 'C++ const' may not be readonly: it could have a
// dynamic initializer.
//
GV->setConstant(true);
} else {
// Mark readonly globals with constant initializers constant.
if (DECL_INITIAL(decl) != error_mark_node && // uninitialized?
DECL_INITIAL(decl) &&
(TREE_CONSTANT(DECL_INITIAL(decl)) ||
TREE_CODE(DECL_INITIAL(decl)) == STRING_CST))
GV->setConstant(true);
}
}
// Set thread local (TLS)
if (TREE_CODE(decl) == VAR_DECL && DECL_THREAD_LOCAL(decl))
GV->setThreadLocal(true);
SET_DECL_LLVM(decl, GV);
}
timevar_pop(TV_LLVM_GLOBALS);
}
/// emit_global_to_llvm - Emit the specified VAR_DECL or aggregate CONST_DECL to
/// LLVM as a global variable. This function implements the end of
/// assemble_variable.
void emit_global_to_llvm(tree decl) {
if (errorcount || sorrycount) return;
// FIXME: Support alignment on globals: DECL_ALIGN.
// FIXME: DECL_PRESERVE_P indicates the var is marked with attribute 'used'.
// Global register variables don't turn into LLVM GlobalVariables.
if (TREE_CODE(decl) == VAR_DECL && DECL_REGISTER(decl))
return;
timevar_push(TV_LLVM_GLOBALS);
// Get or create the global variable now.
GlobalVariable *GV = cast<GlobalVariable>(DECL_LLVM(decl));
// Convert the initializer over.
Constant *Init;
if (DECL_INITIAL(decl) == 0 || DECL_INITIAL(decl) == error_mark_node) {
// This global should be zero initialized. Reconvert the type in case the
// forward def of the global and the real def differ in type (e.g. declared
// as 'int A[]', and defined as 'int A[100]').
Init = Constant::getNullValue(ConvertType(TREE_TYPE(decl)));
} else {
assert((TREE_CONSTANT(DECL_INITIAL(decl)) ||
TREE_CODE(DECL_INITIAL(decl)) == STRING_CST) &&
"Global initializer should be constant!");
// Temporarily set an initializer for the global, so we don't infinitely
// recurse. If we don't do this, we can hit cases where we see "oh a global
// with an initializer hasn't been initialized yet, call emit_global_to_llvm
// on it". When constructing the initializer it might refer to itself.
// this can happen for things like void *G = &G;
//
GV->setInitializer(UndefValue::get(GV->getType()->getElementType()));
Init = TreeConstantToLLVM::Convert(DECL_INITIAL(decl));
}
// If we had a forward definition that has a type that disagrees with our
// initializer, insert a cast now. This sort of thing occurs when we have a
// global union, and the LLVM type followed a union initializer that is
// different from the union element used for the type.
if (GV->getType()->getElementType() != Init->getType()) {
GV->removeFromParent();
GlobalVariable *NGV = new GlobalVariable(Init->getType(), GV->isConstant(),
GlobalValue::ExternalLinkage, 0,
GV->getName(), TheModule);
GV->replaceAllUsesWith(ConstantExpr::getBitCast(NGV, GV->getType()));
delete GV;
SET_DECL_LLVM(decl, NGV);
GV = NGV;
}
// Set the initializer.
GV->setInitializer(Init);
// Set thread local (TLS)
if (TREE_CODE(decl) == VAR_DECL && DECL_THREAD_LOCAL(decl))
GV->setThreadLocal(true);
// Set the linkage.
if (!TREE_PUBLIC(decl)) {
GV->setLinkage(GlobalValue::InternalLinkage);
} else if (DECL_WEAK(decl) || DECL_ONE_ONLY(decl) ||
(DECL_COMMON(decl) && // DECL_COMMON is only meaningful if no init
(!DECL_INITIAL(decl) || DECL_INITIAL(decl) == error_mark_node))) {
// llvm-gcc also includes DECL_VIRTUAL_P here.
GV->setLinkage(GlobalValue::WeakLinkage);
} else if (DECL_COMDAT(decl)) {
GV->setLinkage(GlobalValue::LinkOnceLinkage);
}
#ifdef TARGET_ADJUST_LLVM_LINKAGE
TARGET_ADJUST_LLVM_LINKAGE(GV,decl);
#endif /* TARGET_ADJUST_LLVM_LINKAGE */
// Handle visibility style
if (TREE_PUBLIC(decl)) {
if (DECL_VISIBILITY(decl) == VISIBILITY_HIDDEN)
GV->setVisibility(GlobalValue::HiddenVisibility);
else if (DECL_VISIBILITY(decl) == VISIBILITY_PROTECTED)
GV->setVisibility(GlobalValue::ProtectedVisibility);
}
// Set the section for the global.
if (TREE_CODE(decl) == VAR_DECL || TREE_CODE(decl) == CONST_DECL) {
if (DECL_SECTION_NAME(decl)) {
GV->setSection(TREE_STRING_POINTER(DECL_SECTION_NAME(decl)));
#ifdef LLVM_IMPLICIT_TARGET_GLOBAL_VAR_SECTION
} else if (const char *Section =
LLVM_IMPLICIT_TARGET_GLOBAL_VAR_SECTION(decl)) {
GV->setSection(Section);
#endif
}
// Set the alignment for the global if one of the following condition is met
// 1) DECL_ALIGN_UNIT does not match alignment as per ABI specification
// 2) DECL_ALIGN is set by user.
if (DECL_ALIGN_UNIT(decl)) {
unsigned TargetAlign = getTargetData().getABITypeAlignment(GV->getType()->getElementType());
if (DECL_USER_ALIGN(decl) || TargetAlign != DECL_ALIGN_UNIT(decl))
GV->setAlignment(DECL_ALIGN_UNIT(decl));
}
// Handle used decls
if (DECL_PRESERVE_P (decl)) {
const Type *SBP= PointerType::get(Type::Int8Ty);
AttributeUsedGlobals.push_back(ConstantExpr::getBitCast(GV, SBP));
}
// Add annotate attributes for globals
if (DECL_ATTRIBUTES(decl))
AddAnnotateAttrsToGlobal(GV, decl);
}
if (TheDebugInfo) TheDebugInfo->EmitGlobalVariable(GV, decl);
timevar_pop(TV_LLVM_GLOBALS);
}