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llvm-project/clang/test/PCH/block-helpers.cpp

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[CodeGen] Merge equivalent block copy/helper functions. Clang generates copy and dispose helper functions for each block literal on the stack. Often these functions are equivalent for different blocks. This commit makes changes to merge equivalent copy and dispose helper functions and reduce code size. To enable merging equivalent copy/dispose functions, the captured object infomation is encoded into the helper function name. This allows IRGen to check whether an equivalent helper function has already been emitted and reuse the function instead of generating a new helper function whenever a block is defined. In addition, the helper functions are marked as linkonce_odr to enable merging helper functions that have the same name across translation units and marked as unnamed_addr to enable the linker's deduplication pass to merge functions that have different names but the same content. rdar://problem/42640608 Differential Revision: https://reviews.llvm.org/D50152 llvm-svn: 339438
2018-08-10 23:09:24 +08:00
// RUN: %clang_cc1 -x c++-header -triple x86_64-apple-darwin11 -emit-pch -fblocks -fexceptions -o %t %S/block-helpers.h
// RUN: %clang_cc1 -triple x86_64-apple-darwin11 -include-pch %t -emit-llvm -fblocks -fexceptions -o - %s | FileCheck %s
Distinguish `__block` variables that are captured by escaping blocks from those that aren't. This patch changes the way __block variables that aren't captured by escaping blocks are handled: - Since non-escaping blocks on the stack never get copied to the heap (see https://reviews.llvm.org/D49303), Sema shouldn't error out when the type of a non-escaping __block variable doesn't have an accessible copy constructor. - IRGen doesn't have to use the specialized byref structure (see https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a non-escaping __block variable anymore. Instead IRGen can emit the variable as a normal variable and copy the reference to the block literal. Byref copy/dispose helpers aren't needed either. This reapplies r343518 after fixing a use-after-free bug in function Sema::ActOnBlockStmtExpr where the BlockScopeInfo was dereferenced after it was popped and deleted. rdar://problem/39352313 Differential Revision: https://reviews.llvm.org/D51564 llvm-svn: 343542
2018-10-02 05:51:28 +08:00
// CHECK: %[[STRUCT_BLOCK_BYREF_X:.*]] = type { i8*, %[[STRUCT_BLOCK_BYREF_X]]*, i32, i32, i8*, i8*, %[[STRUCT_S0:.*]] }
// CHECK: %[[STRUCT_S0]] = type { i32 }
// CHECK: %[[STRUCT_BLOCK_BYREF_Y:.*]] = type { i8*, %[[STRUCT_BLOCK_BYREF_Y]]*, i32, i32, i8*, i8*, %[[STRUCT_S0]] }
// CHECK: %[[STRUCT_BLOCK_DESCRIPTOR:.*]] = type { i64, i64 }
// Check that byref structs are allocated for x and y.
// CHECK-LABEL: define linkonce_odr void @_ZN1S1mEv(
// CHECK: %[[X:.*]] = alloca %[[STRUCT_BLOCK_BYREF_X]], align 8
// CHECK: %[[Y:.*]] = alloca %[[STRUCT_BLOCK_BYREF_Y]], align 8
// CHECK: %[[BLOCK:.*]] = alloca <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8* }>, align 8
// CHECK: %[[BLOCK_CAPTURED:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8* }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8* }>* %[[BLOCK]], i32 0, i32 5
// CHECK: %[[V0:.*]] = bitcast %[[STRUCT_BLOCK_BYREF_X]]* %[[X]] to i8*
// CHECK: store i8* %[[V0]], i8** %[[BLOCK_CAPTURED]], align 8
// CHECK: %[[BLOCK_CAPTURED10:.*]] = getelementptr inbounds <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8* }>, <{ i8*, i32, i32, i8*, %[[STRUCT_BLOCK_DESCRIPTOR]]*, i8*, i8* }>* %[[BLOCK]], i32 0, i32 6
// CHECK: %[[V1:.*]] = bitcast %[[STRUCT_BLOCK_BYREF_Y]]* %[[Y]] to i8*
// CHECK: store i8* %[[V1]], i8** %[[BLOCK_CAPTURED10]], align 8
// CHECK-LABEL: define internal void @___ZN1S1mEv_block_invoke(
[CodeGen] Merge equivalent block copy/helper functions. Clang generates copy and dispose helper functions for each block literal on the stack. Often these functions are equivalent for different blocks. This commit makes changes to merge equivalent copy and dispose helper functions and reduce code size. To enable merging equivalent copy/dispose functions, the captured object infomation is encoded into the helper function name. This allows IRGen to check whether an equivalent helper function has already been emitted and reuse the function instead of generating a new helper function whenever a block is defined. In addition, the helper functions are marked as linkonce_odr to enable merging helper functions that have the same name across translation units and marked as unnamed_addr to enable the linker's deduplication pass to merge functions that have different names but the same content. rdar://problem/42640608 Differential Revision: https://reviews.llvm.org/D50152 llvm-svn: 339438
2018-08-10 23:09:24 +08:00
// The second call to block_object_assign should be an invoke.
// CHECK-LABEL: define linkonce_odr hidden void @__copy_helper_block_e8_32rc40rc(
// CHECK: call void @_Block_object_assign(
// CHECK: invoke void @_Block_object_assign(
// CHECK: call void @_Block_object_dispose(
// CHECK-LABEL: define linkonce_odr hidden void @__destroy_helper_block_e8_32r40r(
void test() {
S s;
s.m();
}