Halide 14.0.0
Halide compiler and libraries
CodeGen_LLVM.h
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1#ifndef HALIDE_CODEGEN_LLVM_H
2#define HALIDE_CODEGEN_LLVM_H
3
4/** \file
5 *
6 * Defines the base-class for all architecture-specific code
7 * generators that use llvm.
8 */
9
10namespace llvm {
11class Value;
12class Module;
13class Function;
14class FunctionType;
15class IRBuilderDefaultInserter;
16class ConstantFolder;
17template<typename, typename>
18class IRBuilder;
19class LLVMContext;
20class Type;
21class StructType;
22class Instruction;
23class CallInst;
24class ExecutionEngine;
25class AllocaInst;
26class Constant;
27class Triple;
28class MDNode;
29class NamedMDNode;
30class DataLayout;
31class BasicBlock;
32class GlobalVariable;
33} // namespace llvm
34
35#include <map>
36#include <memory>
37#include <string>
38#include <vector>
39
40#include "IRVisitor.h"
41#include "Module.h"
42#include "Scope.h"
43#include "Target.h"
44
45namespace Halide {
46
47struct ExternSignature;
48
49namespace Internal {
50
51/** A code generator abstract base class. Actual code generators
52 * (e.g. CodeGen_X86) inherit from this. This class is responsible
53 * for taking a Halide Stmt and producing llvm bitcode, machine
54 * code in an object file, or machine code accessible through a
55 * function pointer.
56 */
57class CodeGen_LLVM : public IRVisitor {
58public:
59 /** Create an instance of CodeGen_LLVM suitable for the target. */
60 static std::unique_ptr<CodeGen_LLVM> new_for_target(const Target &target, llvm::LLVMContext &context);
61
62 ~CodeGen_LLVM() override;
63
64 /** Takes a halide Module and compiles it to an llvm Module. */
65 virtual std::unique_ptr<llvm::Module> compile(const Module &module);
66
67 /** The target we're generating code for */
68 const Target &get_target() const {
69 return target;
70 }
71
72 /** Tell the code generator which LLVM context to use. */
73 void set_context(llvm::LLVMContext &context);
74
75 /** Initialize internal llvm state for the enabled targets. */
76 static void initialize_llvm();
77
78 static std::unique_ptr<llvm::Module> compile_trampolines(
79 const Target &target,
80 llvm::LLVMContext &context,
81 const std::string &suffix,
82 const std::vector<std::pair<std::string, ExternSignature>> &externs);
83
86 }
87
88protected:
90
91 /** Compile a specific halide declaration into the llvm Module. */
92 // @{
93 virtual void compile_func(const LoweredFunc &func, const std::string &simple_name, const std::string &extern_name);
94 virtual void compile_buffer(const Buffer<> &buffer);
95 // @}
96
97 /** Helper functions for compiling Halide functions to llvm
98 * functions. begin_func performs all the work necessary to begin
99 * generating code for a function with a given argument list with
100 * the IRBuilder. A call to begin_func should be a followed by a
101 * call to end_func with the same arguments, to generate the
102 * appropriate cleanup code. */
103 // @{
104 virtual void begin_func(LinkageType linkage, const std::string &simple_name,
105 const std::string &extern_name, const std::vector<LoweredArgument> &args);
106 virtual void end_func(const std::vector<LoweredArgument> &args);
107 // @}
108
109 /** What should be passed as -mcpu, -mattrs, and related for
110 * compilation. The architecture-specific code generator should
111 * define these. */
112 // @{
113 virtual std::string mcpu() const = 0;
114 virtual std::string mattrs() const = 0;
115 virtual std::string mabi() const;
116 virtual bool use_soft_float_abi() const = 0;
117 virtual bool use_pic() const;
118 // @}
119
120 /** Should indexing math be promoted to 64-bit on platforms with
121 * 64-bit pointers? */
122 virtual bool promote_indices() const {
123 return true;
124 }
125
126 /** What's the natural vector bit-width to use for loads, stores, etc. */
127 virtual int native_vector_bits() const = 0;
128
129 /** Return the type in which arithmetic should be done for the
130 * given storage type. */
131 virtual Type upgrade_type_for_arithmetic(const Type &) const;
132
133 /** Return the type that a given Halide type should be
134 * stored/loaded from memory as. */
135 virtual Type upgrade_type_for_storage(const Type &) const;
136
137 /** Return the type that a Halide type should be passed in and out
138 * of functions as. */
140
141 std::unique_ptr<llvm::Module> module;
142 llvm::Function *function;
143 llvm::LLVMContext *context;
145 llvm::Value *value;
146 llvm::MDNode *very_likely_branch;
147 llvm::MDNode *default_fp_math_md;
148 llvm::MDNode *strict_fp_math_md;
149 std::vector<LoweredArgument> current_function_args;
150 //@}
151
152 /** The target we're generating code for */
154
155 /** Grab all the context specific internal state. */
156 virtual void init_context();
157 /** Initialize the CodeGen_LLVM internal state to compile a fresh
158 * module. This allows reuse of one CodeGen_LLVM object to compiled
159 * multiple related modules (e.g. multiple device kernels). */
160 virtual void init_module();
161
162 /** Add external_code entries to llvm module. */
163 void add_external_code(const Module &halide_module);
164
165 /** Run all of llvm's optimization passes on the module. */
167
168 /** Add an entry to the symbol table, hiding previous entries with
169 * the same name. Call this when new values come into scope. */
170 void sym_push(const std::string &name, llvm::Value *value);
171
172 /** Remove an entry for the symbol table, revealing any previous
173 * entries with the same name. Call this when values go out of
174 * scope. */
175 void sym_pop(const std::string &name);
176
177 /** Fetch an entry from the symbol table. If the symbol is not
178 * found, it either errors out (if the second arg is true), or
179 * returns nullptr. */
180 llvm::Value *sym_get(const std::string &name,
181 bool must_succeed = true) const;
182
183 /** Test if an item exists in the symbol table. */
184 bool sym_exists(const std::string &name) const;
185
186 /** Given a Halide ExternSignature, return the equivalent llvm::FunctionType. */
187 llvm::FunctionType *signature_to_type(const ExternSignature &signature);
188
189 /** Some useful llvm types */
190 // @{
191 llvm::Type *void_t, *i1_t, *i8_t, *i16_t, *i32_t, *i64_t, *f16_t, *f32_t, *f64_t;
192 llvm::StructType *halide_buffer_t_type,
203
204 // @}
205
206 /** Some wildcard variables used for peephole optimizations in
207 * subclasses */
208 // @{
212
213 // Wildcards for scalars.
217 // @}
218
219 /** Emit code that evaluates an expression, and return the llvm
220 * representation of the result of the expression. */
221 llvm::Value *codegen(const Expr &);
222
223 /** Emit code that runs a statement. */
224 void codegen(const Stmt &);
225
226 /** Codegen a vector Expr by codegenning each lane and combining. */
227 void scalarize(const Expr &);
228
229 /** Some destructors should always be called. Others should only
230 * be called if the pipeline is exiting with an error code. */
234
235 /* Call this at the location of object creation to register how an
236 * object should be destroyed. This does three things:
237 * 1) Emits code here that puts the object in a unique
238 * null-initialized stack slot
239 * 2) Adds an instruction to the destructor block that calls the
240 * destructor on that stack slot if it's not null.
241 * 3) Returns that stack slot, so you can neuter the destructor
242 * (by storing null to the stack slot) or destroy the object early
243 * (by calling trigger_destructor).
244 */
245 llvm::Value *register_destructor(llvm::Function *destructor_fn, llvm::Value *obj, DestructorType when);
246
247 /** Call a destructor early. Pass in the value returned by register destructor. */
248 void trigger_destructor(llvm::Function *destructor_fn, llvm::Value *stack_slot);
249
250 /** Retrieves the block containing the error handling
251 * code. Creates it if it doesn't already exist for this
252 * function. */
253 llvm::BasicBlock *get_destructor_block();
254
255 /** Codegen an assertion. If false, returns the error code (if not
256 * null), or evaluates and returns the message, which must be an
257 * Int(32) expression. */
258 // @{
259 void create_assertion(llvm::Value *condition, const Expr &message, llvm::Value *error_code = nullptr);
260 // @}
261
262 /** Codegen a block of asserts with pure conditions */
263 void codegen_asserts(const std::vector<const AssertStmt *> &asserts);
264
265 /** Return the the pipeline with the given error code. Will run
266 * the destructor block. */
267 void return_with_error_code(llvm::Value *error_code);
268
269 /** Put a string constant in the module as a global variable and return a pointer to it. */
270 llvm::Constant *create_string_constant(const std::string &str);
271
272 /** Put a binary blob in the module as a global variable and return a pointer to it. */
273 llvm::Constant *create_binary_blob(const std::vector<char> &data, const std::string &name, bool constant = true);
274
275 /** Widen an llvm scalar into an llvm vector with the given number of lanes. */
276 llvm::Value *create_broadcast(llvm::Value *, int lanes);
277
278 /** Generate a pointer into a named buffer at a given index, of a
279 * given type. The index counts according to the scalar type of
280 * the type passed in. */
281 // @{
282 llvm::Value *codegen_buffer_pointer(const std::string &buffer, Type type, llvm::Value *index);
283 llvm::Value *codegen_buffer_pointer(const std::string &buffer, Type type, Expr index);
284 llvm::Value *codegen_buffer_pointer(llvm::Value *base_address, Type type, Expr index);
285 llvm::Value *codegen_buffer_pointer(llvm::Value *base_address, Type type, llvm::Value *index);
286 // @}
287
288 /** Turn a Halide Type into an llvm::Value representing a constant halide_type_t */
289 llvm::Value *make_halide_type_t(const Type &);
290
291 /** Mark a load or store with type-based-alias-analysis metadata
292 * so that llvm knows it can reorder loads and stores across
293 * different buffers */
294 void add_tbaa_metadata(llvm::Instruction *inst, std::string buffer, const Expr &index);
295
296 /** Get a unique name for the actual block of memory that an
297 * allocate node uses. Used so that alias analysis understands
298 * when multiple Allocate nodes shared the same memory. */
299 virtual std::string get_allocation_name(const std::string &n) {
300 return n;
301 }
302
303 using IRVisitor::visit;
304
305 /** Generate code for various IR nodes. These can be overridden by
306 * architecture-specific code to perform peephole
307 * optimizations. The result of each is stored in \ref value */
308 // @{
309 void visit(const IntImm *) override;
310 void visit(const UIntImm *) override;
311 void visit(const FloatImm *) override;
312 void visit(const StringImm *) override;
313 void visit(const Cast *) override;
314 void visit(const Variable *) override;
315 void visit(const Add *) override;
316 void visit(const Sub *) override;
317 void visit(const Mul *) override;
318 void visit(const Div *) override;
319 void visit(const Mod *) override;
320 void visit(const Min *) override;
321 void visit(const Max *) override;
322 void visit(const EQ *) override;
323 void visit(const NE *) override;
324 void visit(const LT *) override;
325 void visit(const LE *) override;
326 void visit(const GT *) override;
327 void visit(const GE *) override;
328 void visit(const And *) override;
329 void visit(const Or *) override;
330 void visit(const Not *) override;
331 void visit(const Select *) override;
332 void visit(const Load *) override;
333 void visit(const Ramp *) override;
334 void visit(const Broadcast *) override;
335 void visit(const Call *) override;
336 void visit(const Let *) override;
337 void visit(const LetStmt *) override;
338 void visit(const AssertStmt *) override;
339 void visit(const ProducerConsumer *) override;
340 void visit(const For *) override;
341 void visit(const Store *) override;
342 void visit(const Block *) override;
343 void visit(const IfThenElse *) override;
344 void visit(const Evaluate *) override;
345 void visit(const Shuffle *) override;
346 void visit(const VectorReduce *) override;
347 void visit(const Prefetch *) override;
348 void visit(const Atomic *) override;
349 // @}
350
351 /** Generate code for an allocate node. It has no default
352 * implementation - it must be handled in an architecture-specific
353 * way. */
354 void visit(const Allocate *) override = 0;
355
356 /** Generate code for a free node. It has no default
357 * implementation and must be handled in an architecture-specific
358 * way. */
359 void visit(const Free *) override = 0;
360
361 /** These IR nodes should have been removed during
362 * lowering. CodeGen_LLVM will error out if they are present */
363 // @{
364 void visit(const Provide *) override;
365 void visit(const Realize *) override;
366 // @}
367
368 /** If we have to bail out of a pipeline midway, this should
369 * inject the appropriate target-specific cleanup code. */
370 virtual void prepare_for_early_exit() {
371 }
372
373 /** Get the llvm type equivalent to the given halide type in the
374 * current context. */
375 virtual llvm::Type *llvm_type_of(const Type &) const;
376
377 /** Perform an alloca at the function entrypoint. Will be cleaned
378 * on function exit. */
379 llvm::Value *create_alloca_at_entry(llvm::Type *type, int n,
380 bool zero_initialize = false,
381 const std::string &name = "");
382
383 /** A (very) conservative guess at the size of all alloca() storage requested
384 * (including alignment padding). It's currently meant only to be used as
385 * a very coarse way to ensure there is enough stack space when testing
386 * on the WebAssembly backend.
387 *
388 * It is *not* meant to be a useful proxy for "stack space needed", for a
389 * number of reasons:
390 * - allocas with non-overlapping lifetimes will share space
391 * - on some backends, LLVM may promote register-sized allocas into registers
392 * - while this accounts for alloca() calls we know about, it doesn't attempt
393 * to account for stack spills, function call overhead, etc.
394 */
396
397 /** The user_context argument. May be a constant null if the
398 * function is being compiled without a user context. */
399 llvm::Value *get_user_context() const;
400
401 /** Implementation of the intrinsic call to
402 * interleave_vectors. This implementation allows for interleaving
403 * an arbitrary number of vectors.*/
404 virtual llvm::Value *interleave_vectors(const std::vector<llvm::Value *> &);
405
406 /** Description of an intrinsic function overload. Overloads are resolved
407 * using both argument and return types. The scalar types of the arguments
408 * and return type must match exactly for an overload resolution to succeed. */
409 struct Intrinsic {
411 std::vector<Type> arg_types;
412 llvm::Function *impl;
413
414 Intrinsic(Type result_type, std::vector<Type> arg_types, llvm::Function *impl)
416 }
417 };
418 /** Mapping of intrinsic functions to the various overloads implementing it. */
419 std::map<std::string, std::vector<Intrinsic>> intrinsics;
420
421 /** Get an LLVM intrinsic declaration. If it doesn't exist, it will be created. */
422 llvm::Function *get_llvm_intrin(const Type &ret_type, const std::string &name, const std::vector<Type> &arg_types, bool scalars_are_vectors = false);
423 llvm::Function *get_llvm_intrin(llvm::Type *ret_type, const std::string &name, const std::vector<llvm::Type *> &arg_types);
424 /** Declare an intrinsic function that participates in overload resolution. */
425 llvm::Function *declare_intrin_overload(const std::string &name, const Type &ret_type, const std::string &impl_name, std::vector<Type> arg_types, bool scalars_are_vectors = false);
426 void declare_intrin_overload(const std::string &name, const Type &ret_type, llvm::Function *impl, std::vector<Type> arg_types);
427 /** Call an overloaded intrinsic function. Returns nullptr if no suitable overload is found. */
428 llvm::Value *call_overloaded_intrin(const Type &result_type, const std::string &name, const std::vector<Expr> &args);
429
430 /** Generate a call to a vector intrinsic or runtime inlined
431 * function. The arguments are sliced up into vectors of the width
432 * given by 'intrin_lanes', the intrinsic is called on each
433 * piece, then the results (if any) are concatenated back together
434 * into the original type 't'. For the version that takes an
435 * llvm::Type *, the type may be void, so the vector width of the
436 * arguments must be specified explicitly as
437 * 'called_lanes'. */
438 // @{
439 llvm::Value *call_intrin(const Type &t, int intrin_lanes,
440 const std::string &name, std::vector<Expr>);
441 llvm::Value *call_intrin(const Type &t, int intrin_lanes,
442 llvm::Function *intrin, std::vector<Expr>);
443 llvm::Value *call_intrin(llvm::Type *t, int intrin_lanes,
444 const std::string &name, std::vector<llvm::Value *>);
445 llvm::Value *call_intrin(llvm::Type *t, int intrin_lanes,
446 llvm::Function *intrin, std::vector<llvm::Value *>);
447 // @}
448
449 /** Take a slice of lanes out of an llvm vector. Pads with undefs
450 * if you ask for more lanes than the vector has. */
451 virtual llvm::Value *slice_vector(llvm::Value *vec, int start, int extent);
452
453 /** Concatenate a bunch of llvm vectors. Must be of the same type. */
454 virtual llvm::Value *concat_vectors(const std::vector<llvm::Value *> &);
455
456 /** Create an LLVM shuffle vectors instruction. */
457 virtual llvm::Value *shuffle_vectors(llvm::Value *a, llvm::Value *b,
458 const std::vector<int> &indices);
459 /** Shorthand for shuffling a vector with an undef vector. */
460 llvm::Value *shuffle_vectors(llvm::Value *v, const std::vector<int> &indices);
461
462 /** Go looking for a vector version of a runtime function. Will
463 * return the best match. Matches in the following order:
464 *
465 * 1) The requested vector width.
466 *
467 * 2) The width which is the smallest power of two
468 * greater than or equal to the vector width.
469 *
470 * 3) All the factors of 2) greater than one, in decreasing order.
471 *
472 * 4) The smallest power of two not yet tried.
473 *
474 * So for a 5-wide vector, it tries: 5, 8, 4, 2, 16.
475 *
476 * If there's no match, returns (nullptr, 0).
477 */
478 std::pair<llvm::Function *, int> find_vector_runtime_function(const std::string &name, int lanes);
479
480 virtual bool supports_atomic_add(const Type &t) const;
481
482 /** Compile a horizontal reduction that starts with an explicit
483 * initial value. There are lots of complex ways to peephole
484 * optimize this pattern, especially with the proliferation of
485 * dot-product instructions, and they can usefully share logic
486 * across backends. */
487 virtual void codegen_vector_reduce(const VectorReduce *op, const Expr &init);
488
489 /** Are we inside an atomic node that uses mutex locks?
490 This is used for detecting deadlocks from nested atomics & illegal vectorization. */
492
493 /** Emit atomic store instructions? */
495
496 /** Can we call this operation with float16 type?
497 This is used to avoid "emulated" equivalent code-gen in case target has FP16 feature **/
498 virtual bool supports_call_as_float16(const Call *op) const;
499
500private:
501 /** All the values in scope at the current code location during
502 * codegen. Use sym_push and sym_pop to access. */
503 Scope<llvm::Value *> symbol_table;
504
505 /** String constants already emitted to the module. Tracked to
506 * prevent emitting the same string many times. */
507 std::map<std::string, llvm::Constant *> string_constants;
508
509 /** A basic block to branch to on error that triggers all
510 * destructors. As destructors are registered, code gets added
511 * to this block. */
512 llvm::BasicBlock *destructor_block;
513
514 /** Turn off all unsafe math flags in scopes while this is set. */
515 bool strict_float;
516
517 /** Use the LLVM large code model when this is set. */
518 bool llvm_large_code_model;
519
520 /** Embed an instance of halide_filter_metadata_t in the code, using
521 * the given name (by convention, this should be ${FUNCTIONNAME}_metadata)
522 * as extern "C" linkage. Note that the return value is a function-returning-
523 * pointer-to-constant-data.
524 */
525 llvm::Function *embed_metadata_getter(const std::string &metadata_getter_name,
526 const std::string &function_name, const std::vector<LoweredArgument> &args,
527 const std::map<std::string, std::string> &metadata_name_map);
528
529 /** Embed a constant expression as a global variable. */
530 llvm::Constant *embed_constant_expr(Expr e, llvm::Type *t);
531 llvm::Constant *embed_constant_scalar_value_t(const Expr &e);
532
533 llvm::Function *add_argv_wrapper(llvm::Function *fn, const std::string &name,
534 bool result_in_argv, std::vector<bool> &arg_is_buffer);
535
536 llvm::Value *codegen_dense_vector_load(const Type &type, const std::string &name, const Expr &base,
537 const Buffer<> &image, const Parameter &param, const ModulusRemainder &alignment,
538 llvm::Value *vpred = nullptr, bool slice_to_native = true);
539 llvm::Value *codegen_dense_vector_load(const Load *load, llvm::Value *vpred = nullptr, bool slice_to_native = true);
540
541 virtual void codegen_predicated_load(const Load *op);
542 virtual void codegen_predicated_store(const Store *op);
543
544 void codegen_atomic_rmw(const Store *op);
545
546 void init_codegen(const std::string &name, bool any_strict_float = false);
547 std::unique_ptr<llvm::Module> finish_codegen();
548
549 /** A helper routine for generating folded vector reductions. */
550 template<typename Op>
551 bool try_to_fold_vector_reduce(const Expr &a, Expr b);
552
553 /** Records the StructType for pointer values returned from
554 * make_struct intrinsic. Required for opaque pointer support.
555 * This map should never grow without bound as each entry
556 * represents a unique struct type created by a closure or similar.
557 */
558 std::map<llvm::Value *, llvm::Type *> struct_type_recovery;
559};
560
561} // namespace Internal
562
563/** Given a Halide module, generate an llvm::Module. */
564std::unique_ptr<llvm::Module> codegen_llvm(const Module &module,
565 llvm::LLVMContext &context);
566
567} // namespace Halide
568
569#endif
Defines the base class for things that recursively walk over the IR.
Defines Module, an IR container that fully describes a Halide program.
Defines the Scope class, which is used for keeping track of names in a scope while traversing IR.
Defines the structure that describes a Halide target.
A code generator abstract base class.
Definition: CodeGen_LLVM.h:57
void visit(const Let *) override
std::pair< llvm::Function *, int > find_vector_runtime_function(const std::string &name, int lanes)
Go looking for a vector version of a runtime function.
llvm::StructType * metadata_t_type
Definition: CodeGen_LLVM.h:195
virtual void end_func(const std::vector< LoweredArgument > &args)
llvm::StructType * argument_t_type
Definition: CodeGen_LLVM.h:196
llvm::Constant * create_binary_blob(const std::vector< char > &data, const std::string &name, bool constant=true)
Put a binary blob in the module as a global variable and return a pointer to it.
void visit(const Select *) override
void visit(const Or *) override
void visit(const AssertStmt *) override
bool emit_atomic_stores
Emit atomic store instructions?
Definition: CodeGen_LLVM.h:494
void sym_pop(const std::string &name)
Remove an entry for the symbol table, revealing any previous entries with the same name.
virtual void init_context()
Grab all the context specific internal state.
llvm::StructType * device_interface_t_type
Definition: CodeGen_LLVM.h:198
void visit(const Mul *) override
llvm::StructType * semaphore_t_type
Definition: CodeGen_LLVM.h:200
virtual bool supports_atomic_add(const Type &t) const
virtual llvm::Type * llvm_type_of(const Type &) const
Get the llvm type equivalent to the given halide type in the current context.
std::vector< LoweredArgument > current_function_args
Definition: CodeGen_LLVM.h:149
const Target & get_target() const
The target we're generating code for.
Definition: CodeGen_LLVM.h:68
void return_with_error_code(llvm::Value *error_code)
Return the the pipeline with the given error code.
llvm::Value * call_intrin(llvm::Type *t, int intrin_lanes, const std::string &name, std::vector< llvm::Value * >)
virtual std::unique_ptr< llvm::Module > compile(const Module &module)
Takes a halide Module and compiles it to an llvm Module.
llvm::Value * codegen_buffer_pointer(const std::string &buffer, Type type, Expr index)
llvm::StructType * semaphore_acquire_t_type
Definition: CodeGen_LLVM.h:201
llvm::Function * get_llvm_intrin(llvm::Type *ret_type, const std::string &name, const std::vector< llvm::Type * > &arg_types)
llvm::StructType * parallel_task_t_type
Definition: CodeGen_LLVM.h:202
void trigger_destructor(llvm::Function *destructor_fn, llvm::Value *stack_slot)
Call a destructor early.
void visit(const Min *) override
void visit(const For *) override
llvm::Value * codegen_buffer_pointer(llvm::Value *base_address, Type type, llvm::Value *index)
void visit(const Not *) override
void visit(const Sub *) override
void sym_push(const std::string &name, llvm::Value *value)
Add an entry to the symbol table, hiding previous entries with the same name.
llvm::StructType * type_t_type
Definition: CodeGen_LLVM.h:193
void add_external_code(const Module &halide_module)
Add external_code entries to llvm module.
DestructorType
Some destructors should always be called.
Definition: CodeGen_LLVM.h:231
Halide::Target target
The target we're generating code for.
Definition: CodeGen_LLVM.h:153
virtual void begin_func(LinkageType linkage, const std::string &simple_name, const std::string &extern_name, const std::vector< LoweredArgument > &args)
Helper functions for compiling Halide functions to llvm functions.
llvm::StructType * scalar_value_t_type
Definition: CodeGen_LLVM.h:197
llvm::Value * create_broadcast(llvm::Value *, int lanes)
Widen an llvm scalar into an llvm vector with the given number of lanes.
std::unique_ptr< llvm::Module > module
Definition: CodeGen_LLVM.h:141
virtual void prepare_for_early_exit()
If we have to bail out of a pipeline midway, this should inject the appropriate target-specific clean...
Definition: CodeGen_LLVM.h:370
void visit(const Max *) override
llvm::Value * call_intrin(llvm::Type *t, int intrin_lanes, llvm::Function *intrin, std::vector< llvm::Value * >)
void codegen(const Stmt &)
Emit code that runs a statement.
virtual void compile_buffer(const Buffer<> &buffer)
virtual std::string mcpu() const =0
What should be passed as -mcpu, -mattrs, and related for compilation.
virtual bool promote_indices() const
Should indexing math be promoted to 64-bit on platforms with 64-bit pointers?
Definition: CodeGen_LLVM.h:122
void visit(const GE *) override
void visit(const Variable *) override
void declare_intrin_overload(const std::string &name, const Type &ret_type, llvm::Function *impl, std::vector< Type > arg_types)
void visit(const Atomic *) override
void create_assertion(llvm::Value *condition, const Expr &message, llvm::Value *error_code=nullptr)
Codegen an assertion.
virtual Type upgrade_type_for_storage(const Type &) const
Return the type that a given Halide type should be stored/loaded from memory as.
void visit(const Shuffle *) override
void visit(const Allocate *) override=0
Generate code for an allocate node.
void visit(const Prefetch *) override
void visit(const Provide *) override
These IR nodes should have been removed during lowering.
virtual Type upgrade_type_for_arithmetic(const Type &) const
Return the type in which arithmetic should be done for the given storage type.
void visit(const Div *) override
llvm::StructType * halide_buffer_t_type
Definition: CodeGen_LLVM.h:192
llvm::IRBuilder< llvm::ConstantFolder, llvm::IRBuilderDefaultInserter > * builder
Definition: CodeGen_LLVM.h:144
void visit(const EQ *) override
virtual int native_vector_bits() const =0
What's the natural vector bit-width to use for loads, stores, etc.
llvm::StructType * dimension_t_type
Definition: CodeGen_LLVM.h:194
static std::unique_ptr< llvm::Module > compile_trampolines(const Target &target, llvm::LLVMContext &context, const std::string &suffix, const std::vector< std::pair< std::string, ExternSignature > > &externs)
virtual void compile_func(const LoweredFunc &func, const std::string &simple_name, const std::string &extern_name)
Compile a specific halide declaration into the llvm Module.
llvm::FunctionType * signature_to_type(const ExternSignature &signature)
Given a Halide ExternSignature, return the equivalent llvm::FunctionType.
llvm::Constant * create_string_constant(const std::string &str)
Put a string constant in the module as a global variable and return a pointer to it.
virtual llvm::Value * concat_vectors(const std::vector< llvm::Value * > &)
Concatenate a bunch of llvm vectors.
llvm::LLVMContext * context
Definition: CodeGen_LLVM.h:143
llvm::Value * create_alloca_at_entry(llvm::Type *type, int n, bool zero_initialize=false, const std::string &name="")
Perform an alloca at the function entrypoint.
virtual std::string get_allocation_name(const std::string &n)
Get a unique name for the actual block of memory that an allocate node uses.
Definition: CodeGen_LLVM.h:299
virtual bool use_soft_float_abi() const =0
virtual std::string mabi() const
void visit(const Evaluate *) override
std::map< std::string, std::vector< Intrinsic > > intrinsics
Mapping of intrinsic functions to the various overloads implementing it.
Definition: CodeGen_LLVM.h:419
void visit(const LE *) override
llvm::Value * codegen_buffer_pointer(const std::string &buffer, Type type, llvm::Value *index)
Generate a pointer into a named buffer at a given index, of a given type.
void visit(const NE *) override
void add_tbaa_metadata(llvm::Instruction *inst, std::string buffer, const Expr &index)
Mark a load or store with type-based-alias-analysis metadata so that llvm knows it can reorder loads ...
void visit(const And *) override
virtual bool use_pic() const
void scalarize(const Expr &)
Codegen a vector Expr by codegenning each lane and combining.
void visit(const StringImm *) override
virtual void codegen_vector_reduce(const VectorReduce *op, const Expr &init)
Compile a horizontal reduction that starts with an explicit initial value.
void codegen_asserts(const std::vector< const AssertStmt * > &asserts)
Codegen a block of asserts with pure conditions.
llvm::Function * get_llvm_intrin(const Type &ret_type, const std::string &name, const std::vector< Type > &arg_types, bool scalars_are_vectors=false)
Get an LLVM intrinsic declaration.
size_t get_requested_alloca_total() const
Definition: CodeGen_LLVM.h:84
static std::unique_ptr< CodeGen_LLVM > new_for_target(const Target &target, llvm::LLVMContext &context)
Create an instance of CodeGen_LLVM suitable for the target.
virtual Type upgrade_type_for_argument_passing(const Type &) const
Return the type that a Halide type should be passed in and out of functions as.
void visit(const GT *) override
void visit(const Cast *) override
void visit(const Ramp *) override
void visit(const Broadcast *) override
void visit(const Mod *) override
llvm::Value * make_halide_type_t(const Type &)
Turn a Halide Type into an llvm::Value representing a constant halide_type_t.
void visit(const Call *) override
static void initialize_llvm()
Initialize internal llvm state for the enabled targets.
void set_context(llvm::LLVMContext &context)
Tell the code generator which LLVM context to use.
void visit(const Store *) override
llvm::Value * call_intrin(const Type &t, int intrin_lanes, llvm::Function *intrin, std::vector< Expr >)
llvm::Value * register_destructor(llvm::Function *destructor_fn, llvm::Value *obj, DestructorType when)
llvm::Value * codegen(const Expr &)
Emit code that evaluates an expression, and return the llvm representation of the result of the expre...
void optimize_module()
Run all of llvm's optimization passes on the module.
llvm::Value * codegen_buffer_pointer(llvm::Value *base_address, Type type, Expr index)
llvm::Value * sym_get(const std::string &name, bool must_succeed=true) const
Fetch an entry from the symbol table.
void visit(const ProducerConsumer *) override
virtual llvm::Value * shuffle_vectors(llvm::Value *a, llvm::Value *b, const std::vector< int > &indices)
Create an LLVM shuffle vectors instruction.
void visit(const LT *) override
void visit(const Load *) override
virtual llvm::Value * slice_vector(llvm::Value *vec, int start, int extent)
Take a slice of lanes out of an llvm vector.
llvm::Function * declare_intrin_overload(const std::string &name, const Type &ret_type, const std::string &impl_name, std::vector< Type > arg_types, bool scalars_are_vectors=false)
Declare an intrinsic function that participates in overload resolution.
bool inside_atomic_mutex_node
Are we inside an atomic node that uses mutex locks? This is used for detecting deadlocks from nested ...
Definition: CodeGen_LLVM.h:491
void visit(const FloatImm *) override
void visit(const IntImm *) override
Generate code for various IR nodes.
llvm::Value * call_intrin(const Type &t, int intrin_lanes, const std::string &name, std::vector< Expr >)
Generate a call to a vector intrinsic or runtime inlined function.
llvm::BasicBlock * get_destructor_block()
Retrieves the block containing the error handling code.
virtual void init_module()
Initialize the CodeGen_LLVM internal state to compile a fresh module.
llvm::Value * get_user_context() const
The user_context argument.
virtual std::string mattrs() const =0
void visit(const Realize *) override
void visit(const VectorReduce *) override
void visit(const IfThenElse *) override
size_t requested_alloca_total
A (very) conservative guess at the size of all alloca() storage requested (including alignment paddin...
Definition: CodeGen_LLVM.h:395
Expr wild_u1x_
Some wildcard variables used for peephole optimizations in subclasses.
Definition: CodeGen_LLVM.h:209
llvm::StructType * pseudostack_slot_t_type
Definition: CodeGen_LLVM.h:199
bool sym_exists(const std::string &name) const
Test if an item exists in the symbol table.
void visit(const Free *) override=0
Generate code for a free node.
llvm::Value * shuffle_vectors(llvm::Value *v, const std::vector< int > &indices)
Shorthand for shuffling a vector with an undef vector.
void visit(const Add *) override
void visit(const Block *) override
virtual bool supports_call_as_float16(const Call *op) const
Can we call this operation with float16 type? This is used to avoid "emulated" equivalent code-gen in...
void visit(const UIntImm *) override
void visit(const LetStmt *) override
llvm::Type * void_t
Some useful llvm types.
Definition: CodeGen_LLVM.h:191
llvm::Value * call_overloaded_intrin(const Type &result_type, const std::string &name, const std::vector< Expr > &args)
Call an overloaded intrinsic function.
virtual llvm::Value * interleave_vectors(const std::vector< llvm::Value * > &)
Implementation of the intrinsic call to interleave_vectors.
A base class for algorithms that need to recursively walk over the IR.
Definition: IRVisitor.h:19
virtual void visit(const IntImm *)
A reference-counted handle to a parameter to a halide pipeline.
Definition: Parameter.h:28
A halide module.
Definition: Module.h:172
HALIDE_ALWAYS_INLINE auto intrin(Call::IntrinsicOp intrinsic_op, Args... args) noexcept -> Intrin< decltype(pattern_arg(args))... >
Definition: IRMatch.h:1522
This file defines the class FunctionDAG, which is our representation of a Halide pipeline,...
LinkageType
Type of linkage a function in a lowered Halide module can have.
Definition: Module.h:84
@ Internal
Not visible externally, similar to 'static' linkage in C.
std::unique_ptr< llvm::Module > codegen_llvm(const Module &module, llvm::LLVMContext &context)
Given a Halide module, generate an llvm::Module.
A fragment of Halide syntax.
Definition: Expr.h:256
The sum of two expressions.
Definition: IR.h:38
Allocate a scratch area called with the given name, type, and size.
Definition: IR.h:353
Logical and - are both expressions true.
Definition: IR.h:157
If the 'condition' is false, then evaluate and return the message, which should be a call to an error...
Definition: IR.h:276
Lock all the Store nodes in the body statement.
Definition: IR.h:870
A sequence of statements to be executed in-order.
Definition: IR.h:418
A vector with 'lanes' elements, in which every element is 'value'.
Definition: IR.h:241
A function call.
Definition: IR.h:466
The actual IR nodes begin here.
Definition: IR.h:29
Description of an intrinsic function overload.
Definition: CodeGen_LLVM.h:409
Intrinsic(Type result_type, std::vector< Type > arg_types, llvm::Function *impl)
Definition: CodeGen_LLVM.h:414
The ratio of two expressions.
Definition: IR.h:65
Is the first expression equal to the second.
Definition: IR.h:103
Evaluate and discard an expression, presumably because it has some side-effect.
Definition: IR.h:452
Floating point constants.
Definition: Expr.h:234
A for loop.
Definition: IR.h:747
Free the resources associated with the given buffer.
Definition: IR.h:389
Is the first expression greater than or equal to the second.
Definition: IR.h:148
Is the first expression greater than the second.
Definition: IR.h:139
An if-then-else block.
Definition: IR.h:442
Integer constants.
Definition: Expr.h:216
Is the first expression less than or equal to the second.
Definition: IR.h:130
Is the first expression less than the second.
Definition: IR.h:121
A let expression, like you might find in a functional language.
Definition: IR.h:253
The statement form of a let node.
Definition: IR.h:264
Load a value from a named symbol if predicate is true.
Definition: IR.h:199
Definition of a lowered function.
Definition: Module.h:133
The greater of two values.
Definition: IR.h:94
The lesser of two values.
Definition: IR.h:85
The remainder of a / b.
Definition: IR.h:76
The result of modulus_remainder analysis.
The product of two expressions.
Definition: IR.h:56
Is the first expression not equal to the second.
Definition: IR.h:112
Logical not - true if the expression false.
Definition: IR.h:175
Logical or - is at least one of the expression true.
Definition: IR.h:166
Represent a multi-dimensional region of a Func or an ImageParam that needs to be prefetched.
Definition: IR.h:847
This node is a helpful annotation to do with permissions.
Definition: IR.h:297
This defines the value of a function at a multi-dimensional location.
Definition: IR.h:336
A linear ramp vector node.
Definition: IR.h:229
Allocate a multi-dimensional buffer of the given type and size.
Definition: IR.h:403
A ternary operator.
Definition: IR.h:186
Construct a new vector by taking elements from another sequence of vectors.
Definition: IR.h:778
A reference-counted handle to a statement node.
Definition: Expr.h:417
Store a 'value' to the buffer called 'name' at a given 'index' if 'predicate' is true.
Definition: IR.h:315
String constants.
Definition: Expr.h:243
The difference of two expressions.
Definition: IR.h:47
Unsigned integer constants.
Definition: Expr.h:225
A named variable.
Definition: IR.h:700
Horizontally reduce a vector to a scalar or narrower vector using the given commutative and associati...
Definition: IR.h:888
A struct representing a target machine and os to generate code for.
Definition: Target.h:19
Types in the halide type system.
Definition: Type.h:266