xref: /llvm-project/polly/lib/Support/GICHelper.cpp (revision 75aa1a9a49c9eed40a2fdaabe79fb2ccda5d3fa1)
1 //===- GmpConv.cpp - Recreate LLVM IR from the Scop.  ---------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Functions for converting between gmp objects and apint.
11 //
12 //===----------------------------------------------------------------------===//
13 #include "polly/Support/GICHelper.h"
14 #include "llvm/IR/Value.h"
15 #include "isl/aff.h"
16 #include "isl/map.h"
17 #include "isl/schedule.h"
18 #include "isl/set.h"
19 #include "isl/space.h"
20 #include "isl/union_map.h"
21 #include "isl/union_set.h"
22 #include "isl/val.h"
23 
24 #include <climits>
25 
26 using namespace llvm;
27 
28 __isl_give isl_val *polly::isl_valFromAPInt(isl_ctx *Ctx, const APInt Int,
29                                             bool IsSigned) {
30   APInt Abs;
31   isl_val *v;
32 
33   // As isl is interpreting the input always as unsigned value, we need some
34   // additional pre and post processing to import signed values. The approach
35   // we take is to first obtain the absolute value of Int and then negate the
36   // value after it has been imported to isl.
37   //
38   // It should be noted that the smallest integer value represented in two's
39   // complement with a certain amount of bits does not have a corresponding
40   // positive representation in two's complement representation with the same
41   // number of bits. E.g. 110 (-2) does not have a corresponding value for (2).
42   // To ensure that there is always a corresponding value available we first
43   // sign-extend the input by one bit and only then take the absolute value.
44   if (IsSigned)
45     Abs = Int.sext(Int.getBitWidth() + 1).abs();
46   else
47     Abs = Int;
48 
49   const uint64_t *Data = Abs.getRawData();
50   unsigned Words = Abs.getNumWords();
51 
52   v = isl_val_int_from_chunks(Ctx, Words, sizeof(uint64_t), Data);
53 
54   if (IsSigned && Int.isNegative())
55     v = isl_val_neg(v);
56 
57   return v;
58 }
59 
60 APInt polly::APIntFromVal(__isl_take isl_val *Val) {
61   uint64_t *Data;
62   int NumChunks;
63   const static int ChunkSize = sizeof(uint64_t);
64 
65   assert(isl_val_is_int(Val) && "Only integers can be converted to APInt");
66 
67   NumChunks = isl_val_n_abs_num_chunks(Val, ChunkSize);
68   Data = (uint64_t *)malloc(NumChunks * ChunkSize);
69   isl_val_get_abs_num_chunks(Val, ChunkSize, Data);
70   int NumBits = CHAR_BIT * ChunkSize * NumChunks;
71   APInt A(NumBits, NumChunks, Data);
72 
73   // As isl provides only an interface to obtain data that describes the
74   // absolute value of an isl_val, A at this point always contains a positive
75   // number. In case Val was originally negative, we expand the size of A by
76   // one and negate the value (in two's complement representation). As a result,
77   // the new value in A corresponds now with Val.
78   if (isl_val_is_neg(Val)) {
79     A = A.zext(A.getBitWidth() + 1);
80     A = -A;
81   }
82 
83   // isl may represent small numbers with more than the minimal number of bits.
84   // We truncate the APInt to the minimal number of bits needed to represent the
85   // signed value it contains, to ensure that the bitwidth is always minimal.
86   if (A.getMinSignedBits() < A.getBitWidth())
87     A = A.trunc(A.getMinSignedBits());
88 
89   free(Data);
90   isl_val_free(Val);
91   return A;
92 }
93 
94 template <typename ISLTy, typename ISL_CTX_GETTER, typename ISL_PRINTER>
95 static inline std::string stringFromIslObjInternal(__isl_keep ISLTy *isl_obj,
96                                                    ISL_CTX_GETTER ctx_getter_fn,
97                                                    ISL_PRINTER printer_fn) {
98   if (!isl_obj)
99     return "null";
100   isl_ctx *ctx = ctx_getter_fn(isl_obj);
101   isl_printer *p = isl_printer_to_str(ctx);
102   p = printer_fn(p, isl_obj);
103   char *char_str = isl_printer_get_str(p);
104   std::string string;
105   if (char_str)
106     string = char_str;
107   else
108     string = "null";
109   free(char_str);
110   isl_printer_free(p);
111   return string;
112 }
113 
114 std::string polly::stringFromIslObj(__isl_keep isl_map *map) {
115   return stringFromIslObjInternal(map, isl_map_get_ctx, isl_printer_print_map);
116 }
117 
118 std::string polly::stringFromIslObj(__isl_keep isl_set *set) {
119   return stringFromIslObjInternal(set, isl_set_get_ctx, isl_printer_print_set);
120 }
121 
122 std::string polly::stringFromIslObj(__isl_keep isl_union_map *umap) {
123   return stringFromIslObjInternal(umap, isl_union_map_get_ctx,
124                                   isl_printer_print_union_map);
125 }
126 
127 std::string polly::stringFromIslObj(__isl_keep isl_union_set *uset) {
128   return stringFromIslObjInternal(uset, isl_union_set_get_ctx,
129                                   isl_printer_print_union_set);
130 }
131 
132 std::string polly::stringFromIslObj(__isl_keep isl_schedule *schedule) {
133   return stringFromIslObjInternal(schedule, isl_schedule_get_ctx,
134                                   isl_printer_print_schedule);
135 }
136 
137 std::string polly::stringFromIslObj(__isl_keep isl_multi_aff *maff) {
138   return stringFromIslObjInternal(maff, isl_multi_aff_get_ctx,
139                                   isl_printer_print_multi_aff);
140 }
141 
142 std::string polly::stringFromIslObj(__isl_keep isl_pw_multi_aff *pma) {
143   return stringFromIslObjInternal(pma, isl_pw_multi_aff_get_ctx,
144                                   isl_printer_print_pw_multi_aff);
145 }
146 
147 std::string polly::stringFromIslObj(__isl_keep isl_multi_pw_aff *mpa) {
148   return stringFromIslObjInternal(mpa, isl_multi_pw_aff_get_ctx,
149                                   isl_printer_print_multi_pw_aff);
150 }
151 
152 std::string polly::stringFromIslObj(__isl_keep isl_union_pw_multi_aff *upma) {
153   return stringFromIslObjInternal(upma, isl_union_pw_multi_aff_get_ctx,
154                                   isl_printer_print_union_pw_multi_aff);
155 }
156 
157 std::string polly::stringFromIslObj(__isl_keep isl_aff *aff) {
158   return stringFromIslObjInternal(aff, isl_aff_get_ctx, isl_printer_print_aff);
159 }
160 
161 std::string polly::stringFromIslObj(__isl_keep isl_pw_aff *pwaff) {
162   return stringFromIslObjInternal(pwaff, isl_pw_aff_get_ctx,
163                                   isl_printer_print_pw_aff);
164 }
165 
166 std::string polly::stringFromIslObj(__isl_keep isl_space *space) {
167   return stringFromIslObjInternal(space, isl_space_get_ctx,
168                                   isl_printer_print_space);
169 }
170 
171 static void replace(std::string &str, const std::string &find,
172                     const std::string &replace) {
173   size_t pos = 0;
174   while ((pos = str.find(find, pos)) != std::string::npos) {
175     str.replace(pos, find.length(), replace);
176     pos += replace.length();
177   }
178 }
179 
180 static void makeIslCompatible(std::string &str) {
181   replace(str, ".", "_");
182   replace(str, "\"", "_");
183   replace(str, " ", "__");
184   replace(str, "=>", "TO");
185 }
186 
187 std::string polly::getIslCompatibleName(const std::string &Prefix,
188                                         const std::string &Middle,
189                                         const std::string &Suffix) {
190   std::string S = Prefix + Middle + Suffix;
191   makeIslCompatible(S);
192   return S;
193 }
194 
195 std::string polly::getIslCompatibleName(const std::string &Prefix,
196                                         const Value *Val,
197                                         const std::string &Suffix) {
198   std::string ValStr;
199   raw_string_ostream OS(ValStr);
200   Val->printAsOperand(OS, false);
201   ValStr = OS.str();
202   // Remove the leading %
203   ValStr.erase(0, 1);
204   return getIslCompatibleName(Prefix, ValStr, Suffix);
205 }
206