(llvmType llvm.Type, ptr llvm.Value)
| 272 | } |
| 273 | |
| 274 | func (b *builder) zeroUndefBytes(llvmType llvm.Type, ptr llvm.Value) error { |
| 275 | // We know that hashmapIsBinaryKey is true, so we only have to handle those types that can show up there. |
| 276 | // To zero all undefined bytes, we iterate over all the fields in the type. For each element, compute the |
| 277 | // offset of that element. If it's Basic type, there are no internal padding bytes. For compound types, we recurse to ensure |
| 278 | // we handle nested types. Next, we determine if there are any padding bytes before the next |
| 279 | // element and zero those as well. |
| 280 | |
| 281 | zero := llvm.ConstInt(b.ctx.Int32Type(), 0, false) |
| 282 | |
| 283 | switch llvmType.TypeKind() { |
| 284 | case llvm.IntegerTypeKind: |
| 285 | // no padding bytes |
| 286 | return nil |
| 287 | case llvm.PointerTypeKind: |
| 288 | // mo padding bytes |
| 289 | return nil |
| 290 | case llvm.ArrayTypeKind: |
| 291 | llvmArrayType := llvmType |
| 292 | llvmElemType := llvmType.ElementType() |
| 293 | |
| 294 | for i := 0; i < llvmArrayType.ArrayLength(); i++ { |
| 295 | idx := llvm.ConstInt(b.uintptrType, uint64(i), false) |
| 296 | elemPtr := b.CreateInBoundsGEP(llvmArrayType, ptr, []llvm.Value{zero, idx}, "") |
| 297 | |
| 298 | // zero any padding bytes in this element |
| 299 | b.zeroUndefBytes(llvmElemType, elemPtr) |
| 300 | } |
| 301 | |
| 302 | case llvm.StructTypeKind: |
| 303 | llvmStructType := llvmType |
| 304 | numFields := llvmStructType.StructElementTypesCount() |
| 305 | llvmElementTypes := llvmStructType.StructElementTypes() |
| 306 | |
| 307 | for i := 0; i < numFields; i++ { |
| 308 | idx := llvm.ConstInt(b.ctx.Int32Type(), uint64(i), false) |
| 309 | elemPtr := b.CreateInBoundsGEP(llvmStructType, ptr, []llvm.Value{zero, idx}, "") |
| 310 | |
| 311 | // zero any padding bytes in this field |
| 312 | llvmElemType := llvmElementTypes[i] |
| 313 | b.zeroUndefBytes(llvmElemType, elemPtr) |
| 314 | |
| 315 | // zero any padding bytes before the next field, if any |
| 316 | offset := b.targetData.ElementOffset(llvmStructType, i) |
| 317 | storeSize := b.targetData.TypeStoreSize(llvmElemType) |
| 318 | fieldEndOffset := offset + storeSize |
| 319 | |
| 320 | var nextOffset uint64 |
| 321 | if i < numFields-1 { |
| 322 | nextOffset = b.targetData.ElementOffset(llvmStructType, i+1) |
| 323 | } else { |
| 324 | // Last field? Next offset is the total size of the allocate struct. |
| 325 | nextOffset = b.targetData.TypeAllocSize(llvmStructType) |
| 326 | } |
| 327 | |
| 328 | if fieldEndOffset != nextOffset { |
| 329 | n := llvm.ConstInt(b.uintptrType, nextOffset-fieldEndOffset, false) |
| 330 | llvmStoreSize := llvm.ConstInt(b.uintptrType, storeSize, false) |
| 331 | paddingStart := b.CreateInBoundsGEP(b.ctx.Int8Type(), elemPtr, []llvm.Value{llvmStoreSize}, "") |
no test coverage detected