multiblock-malloc-free.ll 16 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py

; RUN: opt < %s -basic-aa -dse -enable-dse-memoryssa -S | FileCheck %s

target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
declare void @unknown_func()
declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) nounwind
declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) nounwind
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i1) nounwind
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind

declare noalias i8* @calloc(i64, i64) #5
declare noalias i8* @malloc(i64) #0
declare noalias i8* @strdup(i8* nocapture readonly) #1
declare void @free(i8* nocapture) #2

define void @test16(i32* noalias %P) {
; CHECK-LABEL: @test16(
; CHECK-NEXT:    [[P2:%.*]] = bitcast i32* [[P:%.*]] to i8*
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB3:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    call void @free(i8* [[P2]])
; CHECK-NEXT:    store i32 1, i32* [[P]]
; CHECK-NEXT:    ret void
;
  %P2 = bitcast i32* %P to i8*
  store i32 1, i32* %P
  br i1 true, label %bb1, label %bb3
bb1:
  store i32 1, i32* %P
  br label %bb3
bb3:
  call void @free(i8* %P2)
  store i32 1, i32* %P
  ret void
}


define void @test17(i32* noalias %P) {
; CHECK-LABEL: @test17(
; CHECK-NEXT:    [[P2:%.*]] = bitcast i32* [[P:%.*]] to i8*
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB3:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    call void @unknown_func()
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    call void @free(i8* [[P2]])
; CHECK-NEXT:    ret void
;
  %P2 = bitcast i32* %P to i8*
  store i32 1, i32* %P
  br i1 true, label %bb1, label %bb3
bb1:
  call void @unknown_func()
  store i32 1, i32* %P
  br label %bb3
bb3:
  call void @free(i8* %P2)
  ret void
}

define void @test17_read_after_free(i32* noalias %P) {
; CHECK-LABEL: @test17_read_after_free(
; CHECK-NEXT:    [[P2:%.*]] = bitcast i32* [[P:%.*]] to i8*
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB3:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    call void @free(i8* [[P2]])
; CHECK-NEXT:    [[LV:%.*]] = load i8, i8* [[P2]]
; CHECK-NEXT:    ret void
;
  %P2 = bitcast i32* %P to i8*
  store i32 1, i32* %P
  br i1 true, label %bb1, label %bb3
bb1:
  store i32 1, i32* %P
  br label %bb3
bb3:
  call void @free(i8* %P2)
  %lv = load i8, i8* %P2
  ret void
}


define void @test6(i32* noalias %P) {
; CHECK-LABEL: @test6(
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    call void @unknown_func()
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    store i32 0, i32* [[P:%.*]]
; CHECK-NEXT:    ret void
;
  store i32 0, i32* %P
  br i1 true, label %bb1, label %bb2
bb1:
  br label %bb3
bb2:
  call void @unknown_func()
  br label %bb3
bb3:
  store i32 0, i32* %P
  ret void
}

define void @test19(i32* noalias %P) {
; CHECK-LABEL: @test19(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ARRAYIDX0:%.*]] = getelementptr inbounds i32, i32* [[P:%.*]], i64 1
; CHECK-NEXT:    [[P3:%.*]] = bitcast i32* [[ARRAYIDX0]] to i8*
; CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* align 4 [[P3]], i8 0, i64 28, i1 false)
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i32, i32* [[P]], i64 1
; CHECK-NEXT:    store i32 1, i32* [[ARRAYIDX1]], align 4
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    ret void
;
entry:
  %arrayidx0 = getelementptr inbounds i32, i32* %P, i64 1
  %p3 = bitcast i32* %arrayidx0 to i8*
  call void @llvm.memset.p0i8.i64(i8* %p3, i8 0, i64 28, i32 4, i1 false)
  br i1 true, label %bb1, label %bb2
bb1:
  br label %bb3
bb2:
  %arrayidx1 = getelementptr inbounds i32, i32* %P, i64 1
  store i32 1, i32* %arrayidx1, align 4
  br label %bb3
bb3:
  ret void
}


define void @test20(i32* noalias %P) {
; CHECK-LABEL: @test20(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[ARRAYIDX0:%.*]] = getelementptr inbounds i32, i32* [[P:%.*]], i64 1
; CHECK-NEXT:    [[P3:%.*]] = bitcast i32* [[ARRAYIDX0]] to i8*
; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr inbounds i8, i8* [[P3]], i64 4
; CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* align 4 [[TMP0]], i8 0, i64 24, i1 false)
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    [[ARRAYIDX1:%.*]] = getelementptr inbounds i32, i32* [[P]], i64 1
; CHECK-NEXT:    store i32 1, i32* [[ARRAYIDX1]], align 4
; CHECK-NEXT:    ret void
;
entry:
  %arrayidx0 = getelementptr inbounds i32, i32* %P, i64 1
  %p3 = bitcast i32* %arrayidx0 to i8*
  call void @llvm.memset.p0i8.i64(i8* %p3, i8 0, i64 28, i32 4, i1 false)
  br i1 true, label %bb1, label %bb2
bb1:
  br label %bb3
bb2:
  br label %bb3
bb3:
  %arrayidx1 = getelementptr inbounds i32, i32* %P, i64 1
  store i32 1, i32* %arrayidx1, align 4
  ret void
}


define i32 @test22(i32* %P, i32* noalias %Q, i32* %R) {
; CHECK-LABEL: @test22(
; CHECK-NEXT:    store i32 2, i32* [[P:%.*]]
; CHECK-NEXT:    store i32 3, i32* [[Q:%.*]]
; CHECK-NEXT:    [[L:%.*]] = load i32, i32* [[R:%.*]]
; CHECK-NEXT:    ret i32 [[L]]
;
  store i32 1, i32* %Q
  store i32 2, i32* %P
  store i32 3, i32* %Q
  %l = load i32, i32* %R
  ret i32 %l
}


define void @test23(i32* noalias %P) {
; CHECK-LABEL: @test23(
; CHECK-NEXT:    br i1 true, label [[BB1:%.*]], label [[BB2:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    call void @unknown_func()
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    store i32 0, i32* [[P:%.*]]
; CHECK-NEXT:    ret void
;
  br i1 true, label %bb1, label %bb2
bb1:
  store i32 0, i32* %P
  br label %bb3
bb2:
  call void @unknown_func()
  br label %bb3
bb3:
  store i32 0, i32* %P
  ret void
}


define void @test24(i32* noalias %P) {
; CHECK-LABEL: @test24(
; CHECK-NEXT:    br i1 true, label [[BB2:%.*]], label [[BB1:%.*]]
; CHECK:       bb1:
; CHECK-NEXT:    br label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    call void @unknown_func()
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    store i32 0, i32* [[P:%.*]]
; CHECK-NEXT:    ret void
;
  br i1 true, label %bb2, label %bb1
bb1:
  store i32 0, i32* %P
  br label %bb3
bb2:
  call void @unknown_func()
  br label %bb3
bb3:
  store i32 0, i32* %P
  ret void
}

define i8* @test26() {
; CHECK-LABEL: @test26(
; CHECK-NEXT:  bb1:
; CHECK-NEXT:    br i1 true, label [[BB2:%.*]], label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    [[M:%.*]] = call noalias i8* @malloc(i64 10)
; CHECK-NEXT:    store i8 1, i8* [[M]]
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    [[R:%.*]] = phi i8* [ null, [[BB1:%.*]] ], [ [[M]], [[BB2]] ]
; CHECK-NEXT:    ret i8* [[R]]
;
bb1:
  br i1 true, label %bb2, label %bb3
bb2:
  %m = call noalias i8* @malloc(i64 10)
  store i8 1, i8* %m
  br label %bb3
bb3:
  %r = phi i8* [ null, %bb1 ], [ %m, %bb2 ]
  ret i8* %r
}


define void @test27() {
; CHECK-LABEL: @test27(
; CHECK-NEXT:  bb1:
; CHECK-NEXT:    br i1 true, label [[BB2:%.*]], label [[BB3:%.*]]
; CHECK:       bb2:
; CHECK-NEXT:    [[M:%.*]] = call noalias i8* @malloc(i64 10)
; CHECK-NEXT:    br label [[BB3]]
; CHECK:       bb3:
; CHECK-NEXT:    [[R:%.*]] = phi i8* [ null, [[BB1:%.*]] ], [ [[M]], [[BB2]] ]
; CHECK-NEXT:    ret void
;
bb1:
  br i1 true, label %bb2, label %bb3
bb2:
  %m = call noalias i8* @malloc(i64 10)
  store i8 1, i8* %m
  br label %bb3
bb3:
  %r = phi i8* [ null, %bb1 ], [ %m, %bb2 ]
  ret void
}


define i8* @test28() {
; CHECK-LABEL: @test28(
; CHECK-NEXT:  bb0:
; CHECK-NEXT:    [[M:%.*]] = call noalias i8* @malloc(i64 10)
; CHECK-NEXT:    [[MC0:%.*]] = bitcast i8* [[M]] to i8*
; CHECK-NEXT:    [[MC1:%.*]] = bitcast i8* [[MC0]] to i8*
; CHECK-NEXT:    [[MC2:%.*]] = bitcast i8* [[MC1]] to i8*
; CHECK-NEXT:    [[MC3:%.*]] = bitcast i8* [[MC2]] to i8*
; CHECK-NEXT:    [[MC4:%.*]] = bitcast i8* [[MC3]] to i8*
; CHECK-NEXT:    [[MC5:%.*]] = bitcast i8* [[MC4]] to i8*
; CHECK-NEXT:    [[MC6:%.*]] = bitcast i8* [[MC5]] to i8*
; CHECK-NEXT:    [[M0:%.*]] = bitcast i8* [[MC6]] to i8*
; CHECK-NEXT:    store i8 2, i8* [[M]]
; CHECK-NEXT:    ret i8* [[M0]]
;
bb0:
  %m = call noalias i8* @malloc(i64 10)
  %mc0 = bitcast i8* %m to i8*
  %mc1 = bitcast i8* %mc0 to i8*
  %mc2 = bitcast i8* %mc1 to i8*
  %mc3 = bitcast i8* %mc2 to i8*
  %mc4 = bitcast i8* %mc3 to i8*
  %mc5 = bitcast i8* %mc4 to i8*
  %mc6 = bitcast i8* %mc5 to i8*
  %m0 = bitcast i8* %mc6 to i8*
  store i8 2, i8* %m
  ret i8* %m0
}

%struct.SystemCallMapElementStruct = type { i8*, i32, %struct.NodePtrVecStruct* }
%struct.NodePtrVecStruct = type { i32, i32, %struct.NodeStruct** }
%struct.NodeStruct = type { i32, i32, i8*, i32, i32, %struct.NodeStruct*, %struct.NodeListStruct*, %struct.EdgeListStruct*, i32, i32 }
%struct.NodeListStruct = type { %struct.NodeStruct*, %struct.NodeListStruct* }
%struct.EdgeListStruct = type { i32, %struct.NodeStruct*, %struct.EdgeListStruct* }
%struct.SystemCallMapStruct = type { i32, i32, %struct.SystemCallMapElementStruct** }

declare %struct.NodePtrVecStruct* @NodePtrVec_new(i32)

define noalias %struct.SystemCallMapElementStruct* @SystemCallMapElement_new(i8* nocapture readonly %label, i32 %initialSize) {
; CHECK-LABEL: @SystemCallMapElement_new(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CALL:%.*]] = tail call dereferenceable_or_null(24) i8* @malloc(i64 24) #6
; CHECK-NEXT:    [[TMP0:%.*]] = bitcast i8* [[CALL]] to %struct.SystemCallMapElementStruct*
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i8* [[CALL]], null
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[CLEANUP:%.*]], label [[IF_THEN:%.*]]
; CHECK:       if.then:
; CHECK-NEXT:    [[CALL1:%.*]] = tail call i8* @strdup(i8* [[LABEL:%.*]])
; CHECK-NEXT:    [[LABEL2:%.*]] = bitcast i8* [[CALL]] to i8**
; CHECK-NEXT:    store i8* [[CALL1]], i8** [[LABEL2]], align 8
; CHECK-NEXT:    [[INDEX:%.*]] = getelementptr inbounds i8, i8* [[CALL]], i64 8
; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i8* [[INDEX]] to i32*
; CHECK-NEXT:    store i32 -1, i32* [[TMP1]], align 8
; CHECK-NEXT:    [[TOBOOL4:%.*]] = icmp eq i8* [[CALL1]], null
; CHECK-NEXT:    br i1 [[TOBOOL4]], label [[IF_THEN5:%.*]], label [[IF_END:%.*]]
; CHECK:       if.then5:
; CHECK-NEXT:    tail call void @free(i8* nonnull [[CALL]])
; CHECK-NEXT:    br label [[CLEANUP]]
; CHECK:       if.end:
; CHECK-NEXT:    [[CALL6:%.*]] = tail call %struct.NodePtrVecStruct* @NodePtrVec_new(i32 [[INITIALSIZE:%.*]]) #4
; CHECK-NEXT:    [[NODES:%.*]] = getelementptr inbounds i8, i8* [[CALL]], i64 16
; CHECK-NEXT:    [[TMP2:%.*]] = bitcast i8* [[NODES]] to %struct.NodePtrVecStruct**
; CHECK-NEXT:    store %struct.NodePtrVecStruct* [[CALL6]], %struct.NodePtrVecStruct** [[TMP2]], align 8
; CHECK-NEXT:    [[TOBOOL8:%.*]] = icmp eq %struct.NodePtrVecStruct* [[CALL6]], null
; CHECK-NEXT:    br i1 [[TOBOOL8]], label [[IF_THEN9:%.*]], label [[CLEANUP]]
; CHECK:       if.then9:
; CHECK-NEXT:    tail call void @free(i8* nonnull [[CALL]])
; CHECK-NEXT:    br label [[CLEANUP]]
; CHECK:       cleanup:
; CHECK-NEXT:    [[RETVAL_0:%.*]] = phi %struct.SystemCallMapElementStruct* [ null, [[IF_THEN9]] ], [ null, [[IF_THEN5]] ], [ [[TMP0]], [[IF_END]] ], [ [[TMP0]], [[ENTRY:%.*]] ]
; CHECK-NEXT:    ret %struct.SystemCallMapElementStruct* [[RETVAL_0]]
;
entry:
  %call = tail call dereferenceable_or_null(24) i8* @malloc(i64 24) #4
  %0 = bitcast i8* %call to %struct.SystemCallMapElementStruct*
  %tobool = icmp eq i8* %call, null
  br i1 %tobool, label %cleanup, label %if.then

if.then:                                          ; preds = %entry
  %call1 = tail call i8* @strdup(i8* %label)
  %label2 = bitcast i8* %call to i8**
  store i8* %call1, i8** %label2, align 8
  %index = getelementptr inbounds i8, i8* %call, i64 8
  %1 = bitcast i8* %index to i32*
  store i32 -1, i32* %1, align 8
  %tobool4 = icmp eq i8* %call1, null
  br i1 %tobool4, label %if.then5, label %if.end

if.then5:                                         ; preds = %if.then
  tail call void @free(i8* nonnull %call)
  br label %cleanup

if.end:                                           ; preds = %if.then
  %call6 = tail call %struct.NodePtrVecStruct* @NodePtrVec_new(i32 %initialSize) #2
  %nodes = getelementptr inbounds i8, i8* %call, i64 16
  %2 = bitcast i8* %nodes to %struct.NodePtrVecStruct**
  store %struct.NodePtrVecStruct* %call6, %struct.NodePtrVecStruct** %2, align 8
  %tobool8 = icmp eq %struct.NodePtrVecStruct* %call6, null
  br i1 %tobool8, label %if.then9, label %cleanup

if.then9:                                         ; preds = %if.end
  tail call void @free(i8* nonnull %call)
  br label %cleanup

cleanup:                                          ; preds = %entry, %if.end, %if.then9, %if.then5
  %retval.0 = phi %struct.SystemCallMapElementStruct* [ null, %if.then9 ], [ null, %if.then5 ], [ %0, %if.end ], [ %0, %entry ]
  ret %struct.SystemCallMapElementStruct* %retval.0
}

%struct.BitfieldStruct = type { i32, i8* }

define noalias %struct.BitfieldStruct* @Bitfield_new(i32 %bitsNeeded) {
; CHECK-LABEL: @Bitfield_new(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[CALL:%.*]] = tail call dereferenceable_or_null(16) i8* @malloc(i64 16) #6
; CHECK-NEXT:    [[TMP0:%.*]] = bitcast i8* [[CALL]] to %struct.BitfieldStruct*
; CHECK-NEXT:    [[TOBOOL:%.*]] = icmp eq i8* [[CALL]], null
; CHECK-NEXT:    br i1 [[TOBOOL]], label [[CLEANUP:%.*]], label [[IF_END:%.*]]
; CHECK:       if.end:
; CHECK-NEXT:    [[ADD:%.*]] = add nsw i32 [[BITSNEEDED:%.*]], 7
; CHECK-NEXT:    [[DIV:%.*]] = sdiv i32 [[ADD]], 8
; CHECK-NEXT:    [[CONV:%.*]] = sext i32 [[DIV]] to i64
; CHECK-NEXT:    [[CALL1:%.*]] = tail call i8* @calloc(i64 [[CONV]], i64 1) #7
; CHECK-NEXT:    [[BITFIELD:%.*]] = getelementptr inbounds i8, i8* [[CALL]], i64 8
; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i8* [[BITFIELD]] to i8**
; CHECK-NEXT:    store i8* [[CALL1]], i8** [[TMP1]], align 8
; CHECK-NEXT:    [[TOBOOL3:%.*]] = icmp eq i8* [[CALL1]], null
; CHECK-NEXT:    br i1 [[TOBOOL3]], label [[IF_THEN4:%.*]], label [[IF_END5:%.*]]
; CHECK:       if.then4:
; CHECK-NEXT:    tail call void @free(i8* nonnull [[CALL]])
; CHECK-NEXT:    br label [[CLEANUP]]
; CHECK:       if.end5:
; CHECK-NEXT:    [[BITSNEEDED6:%.*]] = bitcast i8* [[CALL]] to i32*
; CHECK-NEXT:    store i32 [[BITSNEEDED]], i32* [[BITSNEEDED6]], align 8
; CHECK-NEXT:    br label [[CLEANUP]]
; CHECK:       cleanup:
; CHECK-NEXT:    [[RETVAL_0:%.*]] = phi %struct.BitfieldStruct* [ [[TMP0]], [[IF_END5]] ], [ null, [[IF_THEN4]] ], [ null, [[ENTRY:%.*]] ]
; CHECK-NEXT:    ret %struct.BitfieldStruct* [[RETVAL_0]]
;
entry:
  %call = tail call dereferenceable_or_null(16) i8* @malloc(i64 16) #4
  %0 = bitcast i8* %call to %struct.BitfieldStruct*
  %tobool = icmp eq i8* %call, null
  br i1 %tobool, label %cleanup, label %if.end

if.end:                                           ; preds = %entry
  %add = add nsw i32 %bitsNeeded, 7
  %div = sdiv i32 %add, 8
  %conv = sext i32 %div to i64
  %call1 = tail call i8* @calloc(i64 %conv, i64 1) #3
  %bitfield = getelementptr inbounds i8, i8* %call, i64 8
  %1 = bitcast i8* %bitfield to i8**
  store i8* %call1, i8** %1, align 8
  %tobool3 = icmp eq i8* %call1, null
  br i1 %tobool3, label %if.then4, label %if.end5

if.then4:                                         ; preds = %if.end
  tail call void @free(i8* nonnull %call)
  br label %cleanup

if.end5:                                          ; preds = %if.end
  %bitsNeeded6 = bitcast i8* %call to i32*
  store i32 %bitsNeeded, i32* %bitsNeeded6, align 8
  br label %cleanup

cleanup:                                          ; preds = %entry, %if.end5, %if.then4
  %retval.0 = phi %struct.BitfieldStruct* [ %0, %if.end5 ], [ null, %if.then4 ], [ null, %entry ]
  ret %struct.BitfieldStruct* %retval.0
}

attributes #0 = { nofree nounwind allocsize(0) }
attributes #1 = { nofree nounwind }
attributes #2 = { nounwind }
attributes #3 = { allocsize(0,1) }
attributes #4 = { allocsize(0) }
attributes #5 = { nofree nounwind allocsize(0,1) }