Halide  14.0.0
Halide compiler and libraries
CodeGen_Internal.h
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1 #ifndef HALIDE_CODEGEN_INTERNAL_H
2 #define HALIDE_CODEGEN_INTERNAL_H
3 
4 /** \file
5  *
6  * Defines functionality that's useful to multiple target-specific
7  * CodeGen paths, but shouldn't live in CodeGen_LLVM.h (because that's the
8  * front-end-facing interface to CodeGen).
9  */
10 
11 #include <memory>
12 #include <string>
13 
14 #include "Closure.h"
15 #include "Expr.h"
16 #include "Scope.h"
17 
18 namespace llvm {
19 class ConstantFolder;
20 class ElementCount;
21 class Function;
22 class IRBuilderDefaultInserter;
23 class LLVMContext;
24 class Module;
25 class StructType;
26 class TargetMachine;
27 class TargetOptions;
28 class Type;
29 class Value;
30 template<typename, typename>
31 class IRBuilder;
32 } // namespace llvm
33 
34 namespace Halide {
35 
36 struct Target;
37 
38 namespace Internal {
39 
40 /** Get the llvm type equivalent to a given halide type */
41 llvm::Type *llvm_type_of(llvm::LLVMContext *context, Halide::Type t);
42 
43 /** Get the number of elements in an llvm vector type, or return 1 if
44  * it's not a vector type. */
45 int get_vector_num_elements(llvm::Type *);
46 
47 /** Get the scalar type of an llvm vector type. Returns the argument
48  * if it's not a vector type. */
49 llvm::Type *get_vector_element_type(llvm::Type *);
50 
51 llvm::ElementCount element_count(int e);
52 
53 llvm::Type *get_vector_type(llvm::Type *, int);
54 
55 /** Which built-in functions require a user-context first argument? */
56 bool function_takes_user_context(const std::string &name);
57 
58 /** Given a size (in bytes), return True if the allocation size can fit
59  * on the stack; otherwise, return False. This routine asserts if size is
60  * non-positive. */
62 
63 /** Does a {div/mod}_round_to_zero using binary long division for int/uint.
64  * max_abs is the maximum absolute value of (a/b).
65  * Returns the pair {div_round_to_zero, mod_round_to_zero}. */
66 std::pair<Expr, Expr> long_div_mod_round_to_zero(const Expr &a, const Expr &b,
67  const uint64_t *max_abs = nullptr);
68 
69 /** Given a Halide Euclidean division/mod operation, do constant optimizations
70  * and possibly call lower_euclidean_div/lower_euclidean_mod if necessary.
71  * Can introduce mulhi_shr and sorted_avg intrinsics as well as those from the
72  * lower_euclidean_ operation -- div_round_to_zero or mod_round_to_zero. */
73 ///@{
74 Expr lower_int_uint_div(const Expr &a, const Expr &b, bool round_to_zero = false);
75 Expr lower_int_uint_mod(const Expr &a, const Expr &b);
76 ///@}
77 
78 /** Given a Halide Euclidean division/mod operation, define it in terms of
79  * div_round_to_zero or mod_round_to_zero. */
80 ///@{
83 ///@}
84 
85 /** Given a Halide shift operation with a signed shift amount (may be negative), define
86  * an equivalent expression using only shifts by unsigned amounts. */
87 ///@{
88 Expr lower_signed_shift_left(const Expr &a, const Expr &b);
89 Expr lower_signed_shift_right(const Expr &a, const Expr &b);
90 ///@}
91 
92 /** Reduce a mux intrinsic to a select tree */
94 
95 /** Given an llvm::Module, set llvm:TargetOptions, cpu and attr information */
96 void get_target_options(const llvm::Module &module, llvm::TargetOptions &options, std::string &mcpu, std::string &mattrs);
97 
98 /** Given two llvm::Modules, clone target options from one to the other */
99 void clone_target_options(const llvm::Module &from, llvm::Module &to);
100 
101 /** Given an llvm::Module, get or create an llvm:TargetMachine */
102 std::unique_ptr<llvm::TargetMachine> make_target_machine(const llvm::Module &module);
103 
104 /** Set the appropriate llvm Function attributes given a Target. */
105 void set_function_attributes_for_target(llvm::Function *, const Target &);
106 
107 /** Save a copy of the llvm IR currently represented by the module as
108  * data in the __LLVM,__bitcode section. Emulates clang's
109  * -fembed-bitcode flag and is useful to satisfy Apple's bitcode
110  * inclusion requirements. */
111 void embed_bitcode(llvm::Module *M, const std::string &halide_command);
112 
113 } // namespace Internal
114 } // namespace Halide
115 
116 #endif
Provides Closure class.
Base classes for Halide expressions (Halide::Expr) and statements (Halide::Internal::Stmt)
Defines the Scope class, which is used for keeping track of names in a scope while traversing IR.
void set_function_attributes_for_target(llvm::Function *, const Target &)
Set the appropriate llvm Function attributes given a Target.
std::pair< Expr, Expr > long_div_mod_round_to_zero(const Expr &a, const Expr &b, const uint64_t *max_abs=nullptr)
Does a {div/mod}_round_to_zero using binary long division for int/uint.
void clone_target_options(const llvm::Module &from, llvm::Module &to)
Given two llvm::Modules, clone target options from one to the other.
llvm::Type * get_vector_element_type(llvm::Type *)
Get the scalar type of an llvm vector type.
Expr lower_int_uint_div(const Expr &a, const Expr &b, bool round_to_zero=false)
Given a Halide Euclidean division/mod operation, do constant optimizations and possibly call lower_eu...
Expr lower_signed_shift_right(const Expr &a, const Expr &b)
Given a Halide shift operation with a signed shift amount (may be negative), define an equivalent exp...
llvm::Type * get_vector_type(llvm::Type *, int)
void embed_bitcode(llvm::Module *M, const std::string &halide_command)
Save a copy of the llvm IR currently represented by the module as data in the __LLVM,...
Expr lower_int_uint_mod(const Expr &a, const Expr &b)
Given a Halide Euclidean division/mod operation, do constant optimizations and possibly call lower_eu...
bool can_allocation_fit_on_stack(int64_t size)
Given a size (in bytes), return True if the allocation size can fit on the stack; otherwise,...
llvm::Type * llvm_type_of(llvm::LLVMContext *context, Halide::Type t)
Get the llvm type equivalent to a given halide type.
llvm::ElementCount element_count(int e)
Expr lower_mux(const Call *mux)
Reduce a mux intrinsic to a select tree.
void get_target_options(const llvm::Module &module, llvm::TargetOptions &options, std::string &mcpu, std::string &mattrs)
Given an llvm::Module, set llvm:TargetOptions, cpu and attr information.
Expr lower_signed_shift_left(const Expr &a, const Expr &b)
Given a Halide shift operation with a signed shift amount (may be negative), define an equivalent exp...
Expr lower_euclidean_div(Expr a, Expr b)
Given a Halide Euclidean division/mod operation, define it in terms of div_round_to_zero or mod_round...
int get_vector_num_elements(llvm::Type *)
Get the number of elements in an llvm vector type, or return 1 if it's not a vector type.
bool function_takes_user_context(const std::string &name)
Which built-in functions require a user-context first argument?
Expr lower_euclidean_mod(Expr a, Expr b)
Given a Halide Euclidean division/mod operation, define it in terms of div_round_to_zero or mod_round...
std::unique_ptr< llvm::TargetMachine > make_target_machine(const llvm::Module &module)
Given an llvm::Module, get or create an llvm:TargetMachine.
This file defines the class FunctionDAG, which is our representation of a Halide pipeline,...
Expr mux(const Expr &id, const std::initializer_list< Expr > &values)
Oftentimes we want to pack a list of expressions with the same type into a channel dimension,...
unsigned __INT64_TYPE__ uint64_t
signed __INT64_TYPE__ int64_t
A fragment of Halide syntax.
Definition: Expr.h:256
A function call.
Definition: IR.h:466
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