[lldb/tool] Add SBGenerator clang tool #1

medismailben · 2025-07-05T21:36:06Z

This patch introduces a new lldb SBGenerator clang tool.

The main goal is to iterate over the lldb SBAPI headers and collect metadata that will be used to dynamically augment the SBAPI by adding new classes or new methods to existing classes.

This first usage of this will be to generate the SBOptional class since we need to make an constructor overload and getter for every SB type.

This patch introduces a new lldb SBGenerator clang tool. The main goal is to iterate over the lldb SBAPI headers and collect metadata that will be used to dynamically augment the SBAPI by adding new classes or new methods to existing classes. This first usage of this will be to generate the SBOptional class since we need to make an constructor overload and getter for every SB type. Signed-off-by: Med Ismail Bennani <[email protected]>

Fix unnecessary conversion of C-String to StringRef in the `Cmp` lambda inside `lookupLLVMIntrinsicByName`. This both fixes an ASAN error in the code that happens when the `Name` StringRef passed in is not a Null terminated StringRef, and additionally can potentially speed up the code as well by eliminating the unnecessary computation of string length every time a C String is converted to StringRef in this code (It seems practically this computation is eliminated in optimized builds, but this will avoid it in O0 builds as well). Added a unit test that demonstrates this issue by building LLVM with these options: ``` CMAKE_BUILD_TYPE=Debug LLVM_USE_SANITIZER=Address LLVM_OPTIMIZE_SANITIZED_BUILDS=OFF ``` The error reported is as follows: ``` ==462665==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x5030000391a2 at pc 0x56525cc30bbf bp 0x7fff9e4ccc60 sp 0x7fff9e4cc428 READ of size 19 at 0x5030000391a2 thread T0 #0 0x56525cc30bbe in strlen (upstream-llvm-second/llvm-project/build/unittests/IR/IRTests+0x713bbe) (BuildId: 0651acf1e582a4d2) #1 0x7f8ff22ad334 in std::char_traits<char>::length(char const*) /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/char_traits.h:399:9 #2 0x7f8ff22a34a0 in llvm::StringRef::StringRef(char const*) /home/rjoshi/upstream-llvm-second/llvm-project/llvm/include/llvm/ADT/StringRef.h:96:33 swiftlang#3 0x7f8ff28ca184 in _ZZL25lookupLLVMIntrinsicByNameN4llvm8ArrayRefIjEENS_9StringRefES2_ENK3$_0clIjPKcEEDaT_T0_ upstream-llvm-second/llvm-project/llvm/lib/IR/Intrinsics.cpp:673:18 ```

…lvm#148205) In the original motivating test case, [FoldList](https://github.com/llvm/llvm-project/blob/d8a2141ff98ee35cd1886f536ccc3548b012820b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp#L1764) had entries: ``` #0: UseMI: %224:sreg_32 = S_OR_B32 %219.sub0:sreg_64, %219.sub1:sreg_64, implicit-def dead $scc UseOpNo: 1 #1: UseMI: %224:sreg_32 = S_OR_B32 %219.sub0:sreg_64, %219.sub1:sreg_64, implicit-def dead $scc UseOpNo: 2 ``` After calling [updateOperand(#0)](https://github.com/llvm/llvm-project/blob/d8a2141ff98ee35cd1886f536ccc3548b012820b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp#L1773), [tryConstantFoldOp(#0.UseMI)](https://github.com/llvm/llvm-project/blob/d8a2141ff98ee35cd1886f536ccc3548b012820b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp#L1786) removed operand 1, and entry #&swiftlang#8203;1.UseOpNo was no longer valid, resulting in an [assert](https://github.com/llvm/llvm-project/blob/4a35214bddbb67f9597a500d48ab8c4fb25af150/llvm/include/llvm/ADT/ArrayRef.h#L452). This change defers constant folding until all operands have been updated so that UseOpNo values remain stable.

M68k's SETCC instruction (`scc`) distinctly fills the destination byte with all 1s. If boolean contents are set to `ZeroOrOneBooleanContent`, LLVM can mistakenly think the destination holds `0x01` instead of `0xff` and emit broken code as a result. This change corrects the boolean content type to `ZeroOrNegativeOneBooleanContent`. For example, this IR: ```llvm define dso_local signext range(i8 0, 2) i8 @testBool(i32 noundef %a) local_unnamed_addr #0 { entry: %cmp = icmp eq i32 %a, 4660 %. = zext i1 %cmp to i8 ret i8 %. } ``` would previously build as: ```asm testBool: ; @testBool cmpi.l swiftlang#4660, (4,%sp) seq %d0 and.l swiftlang#255, %d0 rts ``` Notice the `zext` is erroneously not clearing the low bits, and thus the register returns with 255 instead of 1. This patch fixes the issue: ```asm testBool: ; @testBool cmpi.l swiftlang#4660, (4,%sp) seq %d0 and.l #1, %d0 rts ``` Most of the tests containing `scc` suffered from the same value error as described above, so those tests have been updated to match the new output (which also logically corrects them).

## Problem When the new setting ``` set target.parallel-module-load true ``` was added, lldb began fetching modules from the devices from multiple threads simultaneously. This caused crashes of lldb when debugging on android devices. The top of the stack in the crash look something like this: ``` #0 0x0000555aaf2b27fe llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/llvm/bin/lldb-dap+0xb87fe) #1 0x0000555aaf2b0a99 llvm::sys::RunSignalHandlers() (/opt/llvm/bin/lldb-dap+0xb6a99) #2 0x0000555aaf2b2fda SignalHandler(int, siginfo_t*, void*) (/opt/llvm/bin/lldb-dap+0xb8fda) swiftlang#3 0x00007f9c02444560 __restore_rt /home/engshare/third-party2/glibc/2.34/src/glibc-2.34/signal/../sysdeps/unix/sysv/linux/libc_sigaction.c:13:0 swiftlang#4 0x00007f9c04ea7707 lldb_private::ConnectionFileDescriptor::Disconnect(lldb_private::Status*) (usr/bin/../lib/liblldb.so.15+0x22a7707) swiftlang#5 0x00007f9c04ea5b41 lldb_private::ConnectionFileDescriptor::~ConnectionFileDescriptor() (usr/bin/../lib/liblldb.so.15+0x22a5b41) swiftlang#6 0x00007f9c04ea5c1e lldb_private::ConnectionFileDescriptor::~ConnectionFileDescriptor() (usr/bin/../lib/liblldb.so.15+0x22a5c1e) swiftlang#7 0x00007f9c052916ff lldb_private::platform_android::AdbClient::SyncService::Stat(lldb_private::FileSpec const&, unsigned int&, unsigned int&, unsigned int&) (usr/bin/../lib/liblldb.so.15+0x26916ff) swiftlang#8 0x00007f9c0528b9dc lldb_private::platform_android::PlatformAndroid::GetFile(lldb_private::FileSpec const&, lldb_private::FileSpec const&) (usr/bin/../lib/liblldb.so.15+0x268b9dc) ``` Our workaround was to set `set target.parallel-module-load ` to `false` to avoid the crash. ## Background PlatformAndroid creates two different classes with one stateful adb connection shared between the two -- one through AdbClient and another through AdbClient::SyncService. The connection management and state is complex, and seems to be responsible for the segfault we are seeing. The AdbClient code resets these connections at times, and re-establishes connections if they are not active. Similarly, PlatformAndroid caches its SyncService, which uses an AdbClient class, but the SyncService puts its connection into a different 'sync' state that is incompatible with a standard connection. ## Changes in this diff * This diff refactors the code to (hopefully) have clearer ownership of the connection, clearer separation of AdbClient and SyncService by making a new class for clearer separations of concerns, called AdbSyncService. * New unit tests are added * Additional logs were added (see llvm#145382 (comment) for details)

…namic (llvm#153420) Canonicalizing the following IR: ``` func.func @mul_zero_dynamic_nofold(%arg0: tensor<?x17xf32>) -> tensor<?x17xf32> { %0 = "tosa.const"() <{values = dense<0.000000e+00> : tensor<1x1xf32>}> : () -> tensor<1x1xf32> %1 = "tosa.const"() <{values = dense<0> : tensor<1xi8>}> : () -> tensor<1xi8> %2 = tosa.mul %arg0, %0, %1 : (tensor<?x17xf32>, tensor<1x1xf32>, tensor<1xi8>) -> tensor<?x17xf32> return %2 : tensor<?x17xf32> } ``` resulted in a crash ``` #0 0x000056513187e8db backtrace (./build-release/bin/mlir-opt+0x9d698db) #1 0x0000565131b17737 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/llvm/lib/Support/Unix/Signals.inc:838:8 #2 0x0000565131b187f3 PrintStackTraceSignalHandler(void*) /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/llvm/lib/Support/Unix/Signals.inc:918:1 swiftlang#3 0x0000565131b18c30 llvm::sys::RunSignalHandlers() /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/llvm/lib/Support/Signals.cpp:105:18 swiftlang#4 0x0000565131b18c30 SignalHandler(int, siginfo_t*, void*) /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/llvm/lib/Support/Unix/Signals.inc:409:3 swiftlang#5 0x00007f2e4165b050 (/lib/x86_64-linux-gnu/libc.so.6+0x3c050) swiftlang#6 0x00007f2e416a9eec __pthread_kill_implementation ./nptl/pthread_kill.c:44:76 swiftlang#7 0x00007f2e4165afb2 raise ./signal/../sysdeps/posix/raise.c:27:6 swiftlang#8 0x00007f2e41645472 abort ./stdlib/abort.c:81:7 swiftlang#9 0x00007f2e41645395 _nl_load_domain ./intl/loadmsgcat.c:1177:9 swiftlang#10 0x00007f2e41653ec2 (/lib/x86_64-linux-gnu/libc.so.6+0x34ec2) swiftlang#11 0x00005651443ec4ba mlir::DenseIntOrFPElementsAttr::getRaw(mlir::ShapedType, llvm::ArrayRef<char>) /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/mlir/lib/IR/BuiltinAttributes.cpp:1361:3 swiftlang#12 0x00005651443f1209 mlir::DenseElementsAttr::resizeSplat(mlir::ShapedType) /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/mlir/lib/IR/BuiltinAttributes.cpp:0:10 swiftlang#13 0x000056513f76f2b6 mlir::tosa::MulOp::fold(mlir::tosa::MulOpGenericAdaptor<llvm::ArrayRef<mlir::Attribute>>) /local-ssd/sayans/Softwares/llvm-repo/llvm-project-latest/mlir/lib/Dialect/Tosa/IR/TosaCanonicalizations.cpp:0:0 ``` from the folder for `tosa::mul` since the zero value was being reshaped to `?x17` size which isn't supported. AFAIK, `tosa.const` requires all dimensions to be static. So in this case, the fix is to not to fold the op.

…vm#153560) Fixes llvm#153157 The proposed solution has been discussed here (llvm#153157 (comment)) This is what we would be seeing now ``` base) anutosh491@Anutoshs-MacBook-Air bin % ./lldb /Users/anutosh491/work/xeus-cpp/a.out (lldb) target create "/Users/anutosh491/work/xeus-cpp/a.out" Current executable set to '/Users/anutosh491/work/xeus-cpp/a.out' (arm64). (lldb) b main Breakpoint 1: where = a.out`main, address = 0x0000000100003f90 (lldb) r Process 71227 launched: '/Users/anutosh491/work/xeus-cpp/a.out' (arm64) Process 71227 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1 frame #0: 0x0000000100003f90 a.out`main a.out`main: -> 0x100003f90 <+0>: sub sp, sp, #0x10 0x100003f94 <+4>: str wzr, [sp, #0xc] 0x100003f98 <+8>: str w0, [sp, #0x8] 0x100003f9c <+12>: str x1, [sp] (lldb) expression --repl -l c -- 1> 1 + 1 (int) $0 = 2 2> 2 + 2 (int) $1 = 4 ``` ``` base) anutosh491@Anutoshs-MacBook-Air bin % ./lldb /Users/anutosh491/work/xeus-cpp/a.out (lldb) target create "/Users/anutosh491/work/xeus-cpp/a.out" Current executable set to '/Users/anutosh491/work/xeus-cpp/a.out' (arm64). (lldb) b main Breakpoint 1: where = a.out`main, address = 0x0000000100003f90 (lldb) r Process 71355 launched: '/Users/anutosh491/work/xeus-cpp/a.out' (arm64) Process 71355 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1 frame #0: 0x0000000100003f90 a.out`main a.out`main: -> 0x100003f90 <+0>: sub sp, sp, #0x10 0x100003f94 <+4>: str wzr, [sp, #0xc] 0x100003f98 <+8>: str w0, [sp, #0x8] 0x100003f9c <+12>: str x1, [sp] (lldb) expression --repl -l c -- 3 + 3 Warning: trailing input is ignored in --repl mode 1> 1 + 1 (int) $0 = 2 ```

This can happen when JIT code is run, and we can't symbolize those frames, but they should remain numbered in the stack. An example spidermonkey trace: ``` #0 0x564ac90fb80f (/builds/worker/dist/bin/js+0x240e80f) (BuildId: 5d053c76aad4cfbd08259f8832e7ac78bbeeab58) #1 0x564ac9223a64 (/builds/worker/dist/bin/js+0x2536a64) (BuildId: 5d053c76aad4cfbd08259f8832e7ac78bbeeab58) #2 0x564ac922316f (/builds/worker/dist/bin/js+0x253616f) (BuildId: 5d053c76aad4cfbd08259f8832e7ac78bbeeab58) swiftlang#3 0x564ac9eac032 (/builds/worker/dist/bin/js+0x31bf032) (BuildId: 5d053c76aad4cfbd08259f8832e7ac78bbeeab58) swiftlang#4 0x0dec477ca22e (<unknown module>) ``` Without this change, the following symbolization is output: ``` #0 0x55a6d72f980f in MOZ_CrashSequence /builds/worker/workspace/obj-build/dist/include/mozilla/Assertions.h:248:3 #1 0x55a6d72f980f in Crash(JSContext*, unsigned int, JS::Value*) /builds/worker/checkouts/gecko/js/src/shell/js.cpp:4223:5 #2 0x55a6d7421a64 in CallJSNative(JSContext*, bool (*)(JSContext*, unsigned int, JS::Value*), js::CallReason, JS::CallArgs const&) /builds/worker/checkouts/gecko/js/src/vm/Interpreter.cpp:501:13 swiftlang#3 0x55a6d742116f in js::InternalCallOrConstruct(JSContext*, JS::CallArgs const&, js::MaybeConstruct, js::CallReason) /builds/worker/checkouts/gecko/js/src/vm/Interpreter.cpp:597:12 swiftlang#4 0x55a6d80aa032 in js::jit::DoCallFallback(JSContext*, js::jit::BaselineFrame*, js::jit::ICFallbackStub*, unsigned int, JS::Value*, JS::MutableHandle<JS::Value>) /builds/worker/checkouts/gecko/js/src/jit/BaselineIC.cpp:1705:10 swiftlang#4 0x2c803bd8f22e (<unknown module>) ``` The last frame has a duplicate number. With this change the numbering is correct: ``` #0 0x5620c58ec80f in MOZ_CrashSequence /builds/worker/workspace/obj-build/dist/include/mozilla/Assertions.h:248:3 #1 0x5620c58ec80f in Crash(JSContext*, unsigned int, JS::Value*) /builds/worker/checkouts/gecko/js/src/shell/js.cpp:4223:5 #2 0x5620c5a14a64 in CallJSNative(JSContext*, bool (*)(JSContext*, unsigned int, JS::Value*), js::CallReason, JS::CallArgs const&) /builds/worker/checkouts/gecko/js/src/vm/Interpreter.cpp:501:13 swiftlang#3 0x5620c5a1416f in js::InternalCallOrConstruct(JSContext*, JS::CallArgs const&, js::MaybeConstruct, js::CallReason) /builds/worker/checkouts/gecko/js/src/vm/Interpreter.cpp:597:12 swiftlang#4 0x5620c669d032 in js::jit::DoCallFallback(JSContext*, js::jit::BaselineFrame*, js::jit::ICFallbackStub*, unsigned int, JS::Value*, JS::MutableHandle<JS::Value>) /builds/worker/checkouts/gecko/js/src/jit/BaselineIC.cpp:1705:10 swiftlang#5 0x349f24c7022e (<unknown module>) ```

…gic (llvm#153086) Given the test case: ```llvm define fastcc i16 @testbtst(i16 %a) nounwind { entry: switch i16 %a, label %no [ i16 11, label %yes i16 10, label %yes i16 9, label %yes i16 4, label %yes i16 3, label %yes i16 2, label %yes ] yes: ret i16 1 no: ret i16 0 } ``` We currently get this result: ```asm testbtst: ; @testbtst ; %bb.0: ; %entry move.l %d0, %d1 and.l llvm#65535, %d1 sub.l swiftlang#11, %d1 bhi .LBB0_3 ; %bb.1: ; %entry and.l llvm#65535, %d0 move.l swiftlang#3612, %d1 btst %d0, %d1 bne .LBB0_3 ; <------- Erroneous condition ; %bb.2: ; %yes moveq #1, %d0 rts .LBB0_3: ; %no moveq #0, %d0 rts ``` The cause of this is a line that explicitly reverses the `btst` condition code. But on M68k, `btst` sets condition codes the same as `and` with a bitmask, meaning `EQ` indicates failure (bit is zero) and not success, so the condition does not need to be reversed. In my testing, I've only been able to get switch statements to lower to `btst`, so I wasn't able to explicitly test other options for lowering. But (if possible to trigger) I believe they have the same logical error. For example, in `LowerAndToBTST()`, a comment specifies that it's lowering a case where the `and` result is compared against zero, which means the corresponding `btst` condition should also not be reversed. This patch simply flips the ternary expression in `getBitTestCondition()` to match the ISD condition code with the same M68k code, instead of the opposite.

…vailable (llvm#135343) When a frame is inlined, LLDB will display its name in backtraces as follows: ``` * thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.3 * frame #0: 0x0000000100000398 a.out`func() [inlined] baz(x=10) at inline.cpp:1:42 frame #1: 0x0000000100000398 a.out`func() [inlined] bar() at inline.cpp:2:37 frame #2: 0x0000000100000398 a.out`func() at inline.cpp:4:15 frame swiftlang#3: 0x00000001000003c0 a.out`main at inline.cpp:7:5 frame swiftlang#4: 0x000000026eb29ab8 dyld`start + 6812 ``` The longer the names get the more confusing this gets because the first function name that appears is the parent frame. My assumption (which may need some more surveying) is that for the majority of cases we only care about the actual frame name (not the parent). So this patch removes all the special logic that prints the parent frame. Another quirk of the current format is that the inlined frame name does not abide by the `${function.name-XXX}` format variables. We always just print the raw demangled name. With this patch, we would format the inlined frame name according to the `frame-format` setting (see the test-cases). If we really want to have the `parentFrame [inlined] inlinedFrame` format, we could expose it through a new `frame-format` variable (e..g., `${function.inlined-at-name}` and let the user decide where to place things. (cherry picked from commit 1e153b7)

This were failing on Windows CI with errors like: ``` 22: (lldb) bt 23: * thread #1, stop reason = breakpoint 1.1 24: frame #0: 0x00007ff7c5e41000 TestFrameFormatFunctionFormattedArgumentsObjC.test.tmp.objc.out`func at main.m:2 25: frame #1: 0x00007ff7c5e4101c TestFrameFormatFunctionFormattedArgumentsObjC.test.tmp.objc.out`bar + 12 at main.m:3 26: frame #2: 0x00007ff7c5e4103c TestFrameFormatFunctionFormattedArgumentsObjC.test.tmp.objc.out`main + 16 at main.m:5 27: custom-frame '()' !~~~~~~~~~~~ error: no match expected 28: custom-frame '(__formal=<unavailable>)' ``` (cherry picked from commit cc0bdb3)

* [lldb][nfc] Create helper functions in SwiftLanguageRuntimeNames These will be useful to reuse code in upcoming commits. * [lldb] Fix stepping into ObjcC ctor from Swift When constructing an Objective C object of type `Foo` from Swift, this sequence of function calls is used: ``` * frame #0: 0x000000010000147c test.out`-[Foo initWithString:](self=0x00006000023ec000, _cmd="initWithString:", value=@"Bar") -[Foo initWithString:] at Foo.m:9:21 frame #1: 0x00000001000012bc test.out`@nonobjc Foo.init(string:) $sSo3FooC6stringABSS_tcfcTO at <compiler-generated>:0 frame #2: 0x0000000100001170 test.out`Foo.__allocating_init(string:) $sSo3FooC6stringABSS_tcfC at Foo.h:0 frame swiftlang#3: 0x0000000100000ed8 test.out`work() $s4test4workyyF at main.swift:5:18 ``` Frames 1 and 2 are common with pure Swift classes, and LLDB has a Thread Plan to go from `Foo.allocating_init` -> `Foo.init`. In the case of Objcetive C interop, `Foo.init` has no user code, and is annotated with `@nonobjc`. The debugger needs a plan to go from that code to the Objective C implementation. This is what this patch attempts to fix by creating a plan that runs to any symbol matching `Foo init` (this will match all the :withBlah suffixes). This seems to be the only possible fix for this. While Objective C constructors are not necessarily called init, the interop layer seems to assume this. The only other alternative has some obstacles that could not be easily overcome. Here's the main idea for that. The assembly for `@nonobjc Foo.init` looks like (deleted all non branches): ``` test.out`@nonobjc Foo.init(string:): ... 0x1000012a0 <+20>: bl 0x100001618 ; symbol stub for: Swift.String._bridgeToObjectiveC() -> __C.NSString ... 0x1000012b8 <+44>: bl 0x100001630 ; symbol stub for: objc_msgSend ... 0x1000012e8 <+92>: ret ``` If we had more String arguments, there would be more calls to `_bridgeToObjectiveC`. The call to `objc_msgSend` is the important one, and LLDB knows how to go from that to the target of the message, LLDB has ThreadPlans for that. However, setting a breakpoint on `objc_msgSend` would fail: the calls to `_bridgeToObjectiveC` may also call `objc_msgSend`, so LLDB would end up in the wrong `objc_msgSend`. This is not entirely bad, LLDB would step back to `Foo.init`. Here's the catch: the language runtime refuses to create other plans if PC is not at the start of the function, which makes sense, as it would not be able to distinguish if its job was already done previously or not, unless it had a stateful plan (which it doesn't today).

…142952) (swiftlang#10789) This was removed in llvm#135343 in favour of making it a format variable, which we do here. This follows the precedent of the `[opt]` and `[artificial]` markers. Before: ``` thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.2 * frame #0: 0x000000010000037c a.out`inlined1() at inline.cpp:4:3 frame #1: 0x000000010000037c a.out`regular() at inline.cpp:6:17 frame #2: 0x00000001000003b8 a.out`inlined2() at inline.cpp:7:43 frame swiftlang#3: 0x00000001000003b4 a.out`main at inline.cpp:10:3 frame swiftlang#4: 0x0000000186345be4 dyld`start + 7040 ``` After (note the `[inlined]` markers): ``` thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.2 * frame #0: 0x000000010000037c a.out`inlined1() at inline.cpp:4:3 [inlined] frame #1: 0x000000010000037c a.out`regular() at inline.cpp:6:17 frame #2: 0x00000001000003b8 a.out`inlined2() at inline.cpp:7:43 [inlined] frame swiftlang#3: 0x00000001000003b4 a.out`main at inline.cpp:10:3 frame swiftlang#4: 0x0000000186345be4 dyld`start + 7040 ``` rdar://152642178 (cherry picked from commit 5a91892)

llvm#137975) An authenticated pointer can be explicitly checked by the compiler via a sequence of instructions that executes BRK on failure. It is important to recognize such BRK instruction as checking every register (as it is expected to immediately trigger an abnormal program termination) to prevent false positive reports about authentication oracles: autia x2, x3 autia x0, x1 ; neither x0 nor x2 are checked at this point eor x16, x0, x0, lsl #1 tbz x16, swiftlang#62, on_success ; marks x0 as checked ; end of BB: for x2 to be checked here, it must be checked in both ; successor basic blocks on_failure: brk 0xc470 on_success: ; x2 is checked ldr x1, [x2] ; marks x2 as checked

…build breakage from llvm#155943) (llvm#156103) ASan now detects dereferences of zero-sized allocations (llvm#155943; the corresponding MSan change is llvm#155944). This appears to have detected a bug in CrossOverTest.cpp, causing a buildbot breakage. This patch fixes the test. Buildbot report: https://lab.llvm.org/buildbot/#/builders/4/builds/8732 ``` 7: ==949882==ERROR: AddressSanitizer: heap-buffer-overflow on address 0xf169cfbe0010 at pc 0xb5f45efc6d1c bp 0xffffd933e460 sp 0xffffd933e458 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8: READ of size 1 at 0xf169cfbe0010 thread T0 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 9: #0 0xb5f45efc6d18 in LLVMFuzzerTestOneInput /home/tcwg-buildbot/worker/clang-aarch64-sve-vls-2stage/llvm/compiler-rt/test/fuzzer/CrossOverTest.cpp:48:7 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ check:20'1 ? possible intended match 10: #1 0xb5f45eec7288 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) /home/tcwg-buildbot/worker/clang-aarch64-sve-vls-2stage/llvm/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:619:13 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11: #2 0xb5f45eec85d4 in fuzzer::Fuzzer::ReadAndExecuteSeedCorpora(std::vector<fuzzer::SizedFile, std::allocator<fuzzer::SizedFile>>&) /home/tcwg-buildbot/worker/clang-aarch64-sve-vls-2stage/llvm/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:812:3 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 12: swiftlang#3 0xb5f45eec8c60 in fuzzer::Fuzzer::Loop(std::vector<fuzzer::SizedFile, std::allocator<fuzzer::SizedFile>>&) /home/tcwg-buildbot/worker/clang-aarch64-sve-vls-2stage/llvm/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:872:3 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 13: swiftlang#4 0xb5f45eeb5c64 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) /home/tcwg-buildbot/worker/clang-aarch64-sve-vls-2stage/llvm/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:923:6 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14: swiftlang#5 0xb5f45eee09d0 in main /home/tcwg-buildbot/worker/clang-aarch64-sve-vls-2stage/llvm/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10 check:20'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ``` For context, FuzzerLoop.cpp:812 tries empty input: ``` 810 // Test the callback with empty input and never try it again. 811 uint8_t dummy = 0; 812 ExecuteCallback(&dummy, 0); ```

Reverts llvm#154949 due to suspected buildbot breakage (https://lab.llvm.org/buildbot/#/builders/55/builds/16630/steps/11/logs/stdio). Previously commented on the original pull request: llvm#154949 (comment) ``` ******************** TEST 'MLIR :: Dialect/XeGPU/subgroup-distribute.mlir' FAILED ******************** ... # | PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace. # | Stack dump: # | 0. Program arguments: /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm_build_hwasan/bin/mlir-opt -xegpu-subgroup-distribute -allow-unregistered-dialect -canonicalize -cse -split-input-file /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/test/Dialect/XeGPU/subgroup-distribute.mlir # | #0 0x0000c0af4b066df0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/lib/Support/Unix/Signals.inc:834:13 # | #1 0x0000c0af4b060e20 llvm::sys::RunSignalHandlers() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/lib/Support/Signals.cpp:105:18 # | #2 0x0000c0af4b0691b4 SignalHandler(int, siginfo_t*, void*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/llvm/lib/Support/Unix/Signals.inc:426:38 # | swiftlang#3 0x0000ee25a3dcb8f8 (linux-vdso.so.1+0x8f8) # | swiftlang#4 0x0000ee25a36c7608 (/lib/aarch64-linux-gnu/libc.so.6+0x87608) # | swiftlang#5 0x0000ee25a367cb3c raise (/lib/aarch64-linux-gnu/libc.so.6+0x3cb3c) # | swiftlang#6 0x0000ee25a3667e00 abort (/lib/aarch64-linux-gnu/libc.so.6+0x27e00) # | swiftlang#7 0x0000c0af4ae7e4b0 __sanitizer::Atexit(void (*)()) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_posix_libcdep.cpp:168:10 # | swiftlang#8 0x0000c0af4ae7c354 __sanitizer::Die() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_termination.cpp:52:5 # | swiftlang#9 0x0000c0af4ae66a30 Unlock /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_mutex.h:250:16 # | swiftlang#10 0x0000c0af4ae66a30 ~GenericScopedLock /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_mutex.h:386:51 # | swiftlang#11 0x0000c0af4ae66a30 __hwasan::ScopedReport::~ScopedReport() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan_report.cpp:54:5 # | swiftlang#12 0x0000c0af4ae661b8 __hwasan::(anonymous namespace)::BaseReport::~BaseReport() /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan_report.cpp:477:7 # | swiftlang#13 0x0000c0af4ae63f5c __hwasan::ReportTagMismatch(__sanitizer::StackTrace*, unsigned long, unsigned long, bool, bool, unsigned long*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan_report.cpp:1094:1 # | swiftlang#14 0x0000c0af4ae4f8e0 Destroy /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_common.h:532:31 # | swiftlang#15 0x0000c0af4ae4f8e0 ~InternalMmapVector /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/../sanitizer_common/sanitizer_common.h:642:56 # | swiftlang#16 0x0000c0af4ae4f8e0 __hwasan::HandleTagMismatch(__hwasan::AccessInfo, unsigned long, unsigned long, void*, unsigned long*) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan.cpp:245:1 # | swiftlang#17 0x0000c0af4ae51e8c __hwasan_tag_mismatch4 /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/hwasan/hwasan.cpp:764:1 # | swiftlang#18 0x0000c0af4ae67b30 __interception::InterceptFunction(char const*, unsigned long*, unsigned long, unsigned long) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/compiler-rt/lib/interception/interception_linux.cpp:60:0 # | swiftlang#19 0x0000c0af5641cd24 getNumResults /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/include/mlir/IR/Operation.h:404:37 # | swiftlang#20 0x0000c0af5641cd24 getOpResultImpl /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/include/mlir/IR/Operation.h:1010:5 # | swiftlang#21 0x0000c0af5641cd24 getResult /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/include/mlir/IR/Operation.h:407:54 # | swiftlang#22 0x0000c0af5641cd24 mlir::OpTrait::detail::MultiResultTraitBase<mlir::gpu::WarpExecuteOnLane0Op, mlir::OpTrait::VariadicResults>::getResult(unsigned int) /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/include/mlir/IR/OpDefinition.h:638:62 # | swiftlang#23 0x0000c0af56426b60 getType /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/include/mlir/IR/Value.h:63:33 # | swiftlang#24 0x0000c0af56426b60 getType /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/include/mlir/IR/Value.h:105:39 # | swiftlang#25 0x0000c0af56426b60 (anonymous namespace)::LoadDistribution::matchAndRewrite(mlir::gpu::WarpExecuteOnLane0Op, mlir::PatternRewriter&) const /home/b/sanitizer-aarch64-linux-bootstrap-hwasan/build/llvm-project/mlir/lib/Dialect/XeGPU/Transforms/XeGPUSubgroupDistribute.cpp:991:55 ... ```

Some downstream work broke these tests because the attribute number changed. Refactor these tests to be more resilient in the face of changes like this * `instrument-objc-method.m` * `#1` was never checked, I think it was trying to check that `__cyg_profile_func_enter` was not used, so I added `--implicit-check-not="__cyg_profile_func_enter"` * Use `[[#ATTR:]]` so the test doesn't fail if the number changes * `address-safety-attr.mm` * Check attributes in `Function Attrs:` so it's independent of the attribute number

A recent change adding a new sanitizer kind (via Sanitizers.def) was reverted in c74fa20 ("Revert "[Clang][CodeGen] Introduce the AllocToken SanitizerKind" (llvm#162413)"). The reason was this ASan report, when running the test cases in clang/test/Preprocessor/print-header-json.c: ``` ==clang==483265==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7d82b97e8b58 at pc 0x562cd432231f bp 0x7fff3fad0850 sp 0x7fff3fad0848 READ of size 16 at 0x7d82b97e8b58 thread T0 #0 0x562cd432231e in __copy_non_overlapping_range<const unsigned long *, const unsigned long *> zorg-test/libcxx_install_asan_ubsan/include/c++/v1/string:2144:38 #1 0x562cd432231e in void std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>::__init_with_size[abi:nn220000]<unsigned long const*, unsigned long const*>(unsigned long const*, unsigned long const*, unsigned long) zorg-test/libcxx_install_asan_ubsan/include/c++/v1/string:2685:18 #2 0x562cd41e2797 in __init<const unsigned long *, 0> zorg-test/libcxx_install_asan_ubsan/include/c++/v1/string:2673:3 swiftlang#3 0x562cd41e2797 in basic_string<const unsigned long *, 0> zorg-test/libcxx_install_asan_ubsan/include/c++/v1/string:1174:5 swiftlang#4 0x562cd41e2797 in clang::ASTReader::ReadString(llvm::SmallVectorImpl<unsigned long> const&, unsigned int&) clang/lib/Serialization/ASTReader.cpp:10171:15 swiftlang#5 0x562cd41fd89a in clang::ASTReader::ParseLanguageOptions(llvm::SmallVector<unsigned long, 64u> const&, llvm::StringRef, bool, clang::ASTReaderListener&, bool) clang/lib/Serialization/ASTReader.cpp:6475:28 swiftlang#6 0x562cd41eea53 in clang::ASTReader::ReadOptionsBlock(llvm::BitstreamCursor&, llvm::StringRef, unsigned int, bool, clang::ASTReaderListener&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>&) clang/lib/Serialization/ASTReader.cpp:3069:11 swiftlang#7 0x562cd4204ab8 in clang::ASTReader::ReadControlBlock(clang::serialization::ModuleFile&, llvm::SmallVectorImpl<clang::ASTReader::ImportedModule>&, clang::serialization::ModuleFile const*, unsigned int) clang/lib/Serialization/ASTReader.cpp:3249:15 swiftlang#8 0x562cd42097d2 in clang::ASTReader::ReadASTCore(llvm::StringRef, clang::serialization::ModuleKind, clang::SourceLocation, clang::serialization::ModuleFile*, llvm::SmallVectorImpl<clang::ASTReader::ImportedModule>&, long, long, clang::ASTFileSignature, unsigned int) clang/lib/Serialization/ASTReader.cpp:5182:15 swiftlang#9 0x562cd421ec77 in clang::ASTReader::ReadAST(llvm::StringRef, clang::serialization::ModuleKind, clang::SourceLocation, unsigned int, clang::serialization::ModuleFile**) clang/lib/Serialization/ASTReader.cpp:4828:11 swiftlang#10 0x562cd3d07b74 in clang::CompilerInstance::findOrCompileModuleAndReadAST(llvm::StringRef, clang::SourceLocation, clang::SourceLocation, bool) clang/lib/Frontend/CompilerInstance.cpp:1805:27 swiftlang#11 0x562cd3d0b2ef in clang::CompilerInstance::loadModule(clang::SourceLocation, llvm::ArrayRef<clang::IdentifierLoc>, clang::Module::NameVisibilityKind, bool) clang/lib/Frontend/CompilerInstance.cpp:1956:31 swiftlang#12 0x562cdb04eb1c in clang::Preprocessor::HandleHeaderIncludeOrImport(clang::SourceLocation, clang::Token&, clang::Token&, clang::SourceLocation, clang::detail::SearchDirIteratorImpl<true>, clang::FileEntry const*) clang/lib/Lex/PPDirectives.cpp:2423:49 swiftlang#13 0x562cdb042222 in clang::Preprocessor::HandleIncludeDirective(clang::SourceLocation, clang::Token&, clang::detail::SearchDirIteratorImpl<true>, clang::FileEntry const*) clang/lib/Lex/PPDirectives.cpp:2101:17 swiftlang#14 0x562cdb043366 in clang::Preprocessor::HandleDirective(clang::Token&) clang/lib/Lex/PPDirectives.cpp:1338:14 swiftlang#15 0x562cdafa84bc in clang::Lexer::LexTokenInternal(clang::Token&, bool) clang/lib/Lex/Lexer.cpp:4512:7 swiftlang#16 0x562cdaf9f20b in clang::Lexer::Lex(clang::Token&) clang/lib/Lex/Lexer.cpp:3729:24 swiftlang#17 0x562cdb0d4ffa in clang::Preprocessor::Lex(clang::Token&) clang/lib/Lex/Preprocessor.cpp:896:11 swiftlang#18 0x562cd77da950 in clang::ParseAST(clang::Sema&, bool, bool) clang/lib/Parse/ParseAST.cpp:163:7 [...] 0x7d82b97e8b58 is located 0 bytes after 3288-byte region [0x7d82b97e7e80,0x7d82b97e8b58) allocated by thread T0 here: #0 0x562cca76f604 in malloc zorg-test/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:67:3 #1 0x562cd1cce452 in safe_malloc llvm/include/llvm/Support/MemAlloc.h:26:18 #2 0x562cd1cce452 in llvm::SmallVectorBase<unsigned int>::grow_pod(void*, unsigned long, unsigned long) llvm/lib/Support/SmallVector.cpp:151:15 swiftlang#3 0x562cdbe1768b in grow_pod llvm/include/llvm/ADT/SmallVector.h:139:11 swiftlang#4 0x562cdbe1768b in grow llvm/include/llvm/ADT/SmallVector.h:525:41 swiftlang#5 0x562cdbe1768b in reserve llvm/include/llvm/ADT/SmallVector.h:665:13 swiftlang#6 0x562cdbe1768b in llvm::BitstreamCursor::readRecord(unsigned int, llvm::SmallVectorImpl<unsigned long>&, llvm::StringRef*) llvm/lib/Bitstream/Reader/BitstreamReader.cpp:230:10 swiftlang#7 0x562cd41ee8ab in clang::ASTReader::ReadOptionsBlock(llvm::BitstreamCursor&, llvm::StringRef, unsigned int, bool, clang::ASTReaderListener&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>&) clang/lib/Serialization/ASTReader.cpp:3060:49 swiftlang#8 0x562cd4204ab8 in clang::ASTReader::ReadControlBlock(clang::serialization::ModuleFile&, llvm::SmallVectorImpl<clang::ASTReader::ImportedModule>&, clang::serialization::ModuleFile const*, unsigned int) clang/lib/Serialization/ASTReader.cpp:3249:15 swiftlang#9 0x562cd42097d2 in clang::ASTReader::ReadASTCore(llvm::StringRef, clang::serialization::ModuleKind, clang::SourceLocation, clang::serialization::ModuleFile*, llvm::SmallVectorImpl<clang::ASTReader::ImportedModule>&, long, long, clang::ASTFileSignature, unsigned int) clang/lib/Serialization/ASTReader.cpp:5182:15 swiftlang#10 0x562cd421ec77 in clang::ASTReader::ReadAST(llvm::StringRef, clang::serialization::ModuleKind, clang::SourceLocation, unsigned int, clang::serialization::ModuleFile**) clang/lib/Serialization/ASTReader.cpp:4828:11 swiftlang#11 0x562cd3d07b74 in clang::CompilerInstance::findOrCompileModuleAndReadAST(llvm::StringRef, clang::SourceLocation, clang::SourceLocation, bool) clang/lib/Frontend/CompilerInstance.cpp:1805:27 swiftlang#12 0x562cd3d0b2ef in clang::CompilerInstance::loadModule(clang::SourceLocation, llvm::ArrayRef<clang::IdentifierLoc>, clang::Module::NameVisibilityKind, bool) clang/lib/Frontend/CompilerInstance.cpp:1956:31 swiftlang#13 0x562cdb04eb1c in clang::Preprocessor::HandleHeaderIncludeOrImport(clang::SourceLocation, clang::Token&, clang::Token&, clang::SourceLocation, clang::detail::SearchDirIteratorImpl<true>, clang::FileEntry const*) clang/lib/Lex/PPDirectives.cpp:2423:49 swiftlang#14 0x562cdb042222 in clang::Preprocessor::HandleIncludeDirective(clang::SourceLocation, clang::Token&, clang::detail::SearchDirIteratorImpl<true>, clang::FileEntry const*) clang/lib/Lex/PPDirectives.cpp:2101:17 swiftlang#15 0x562cdb043366 in clang::Preprocessor::HandleDirective(clang::Token&) clang/lib/Lex/PPDirectives.cpp:1338:14 swiftlang#16 0x562cdafa84bc in clang::Lexer::LexTokenInternal(clang::Token&, bool) clang/lib/Lex/Lexer.cpp:4512:7 swiftlang#17 0x562cdaf9f20b in clang::Lexer::Lex(clang::Token&) clang/lib/Lex/Lexer.cpp:3729:24 swiftlang#18 0x562cdb0d4ffa in clang::Preprocessor::Lex(clang::Token&) clang/lib/Lex/Preprocessor.cpp:896:11 swiftlang#19 0x562cd77da950 in clang::ParseAST(clang::Sema&, bool, bool) clang/lib/Parse/ParseAST.cpp:163:7 [...] SUMMARY: AddressSanitizer: heap-buffer-overflow clang/lib/Serialization/ASTReader.cpp:10171:15 in clang::ASTReader::ReadString(llvm::SmallVectorImpl<unsigned long> const&, unsigned int&) ``` The reason is this particular RUN line: ``` // RUN: env CC_PRINT_HEADERS_FORMAT=json CC_PRINT_HEADERS_FILTERING=direct-per-file CC_PRINT_HEADERS_FILE=%t.txt %clang -fsyntax-only -I %S/Inputs/print-header-json -isystem %S/Inputs/print-header-json/system -fmodules -fimplicit-module-maps -fmodules-cache-path=%t %s -o /dev/null ``` which was added in 8df194f ("[Clang] Support includes translated to module imports in -header-include-filtering=direct-per-file (llvm#156756)"). The problem is caused by an incremental build reusing stale cached module files (.pcm) that are no longer binary-compatible with the updated compiler. Adding a new sanitizer option altered the implicit binary layout of the serialized LangOptions data structure. The build + test system is oblivious to such changes. When the new compiler attempted to read the old module file (from the previous test invocation), it misinterpreted the data due to the layout mismatch, resulting in a heap-buffer-overflow. Unfortunately Clang's PCM format does not encode nor detect version mismatches here; a more graceful failure mode would be preferable. For now, fix the test to be more robust with incremental build + test.

Otherwise debug-info is stripped, which influences the language of the current frame. Also, set explicit breakpoint because Windows seems to not obey the debugtrap. Log from failing test on Windows: ``` (lldb) command source -s 0 'lit-lldb-init-quiet' Executing commands in 'D:\test\lit-lldb-init-quiet'. (lldb) command source -C --silent-run true lit-lldb-init (lldb) target create "main.out" Current executable set to 'D:\test\main.out' (x86_64). (lldb) settings set interpreter.stop-command-source-on-error false (lldb) command source -s 0 'with-target.input' Executing commands in 'D:\test\with-target.input'. (lldb) expr blah ^ error: use of undeclared identifier 'blah' note: Falling back to default language. Ran expression as 'Objective C++'. (lldb) run Process 29404 launched: 'D:\test\main.out' (x86_64) Process 29404 stopped * thread #1, stop reason = Exception 0x80000003 encountered at address 0x7ff7b3df7189 frame #0: 0x00007ff7b3df718a main.out -> 0x7ff7b3df718a: xorl %eax, %eax 0x7ff7b3df718c: popq %rcx 0x7ff7b3df718d: retq 0x7ff7b3df718e: int3 (lldb) expr blah ^ error: use of undeclared identifier 'blah' note: Falling back to default language. Ran expression as 'Objective C++'. (lldb) expr -l objc -- blah ^ error: use of undeclared identifier 'blah' note: Expression evaluation in pure Objective-C not supported. Ran expression as 'Objective C++'. (lldb) expr -l c -- blah ^ error: use of undeclared identifier 'blah' note: Expression evaluation in pure C not supported. Ran expression as 'ISO C++'. ```

The Tkinter module was renamed to tkinter in Python 3.0. https://docs.python.org/2/library/tkinter.html https://docs.python.org/3/library/tkinter.html Rest of it appears to work when imported inside of LLDB: ``` $ ./bin/lldb /tmp/test.o (lldb) target create "/tmp/test.o" Current executable set to '/tmp/test.o' (x86_64). (lldb) b main Breakpoint 1: where = test.o`main + 8 at test.c:1:18, address = 0x0000000000001131 (lldb) run Process 121572 launched: '/tmp/test.o' (x86_64) Process 121572 stopped * thread #1, name = 'test.o', stop reason = breakpoint 1.1 frame #0: 0x0000555555555131 test.o`main at test.c:1:18 -> 1 int main() { int a = 1; char b = '?'; return 0; } (lldb) command script import <...>/llvm-project/lldb/examples/python/lldbtk.py (lldb) tk- Available completions: tk-process -- For more information run 'help tk-process' tk-target -- For more information run 'help tk-target' tk-variables -- For more information run 'help tk-variables' (lldb) tk-process (lldb) tk-target (lldb) tk-variables ```

…ypes (llvm#162278) When we take the following C program: ``` int main() { return 0; } ``` and create a statically-linked executable from it: ``` clang -static -g -o main main.c ``` Then we can observe the following `lldb` behavior: ``` $ lldb (lldb) target create main Current executable set to '.../main' (x86_64). (lldb) breakpoint set --name main Breakpoint 1: where = main`main + 11 at main.c:2:3, address = 0x000000000022aa7b (lldb) process launch Process 3773637 launched: '/home/me/tmp/built-in/main' (x86_64) Process 3773637 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000000000022aa7b main`main at main.c:2:3 1 int main() { -> 2 return 0; 3 } (lldb) script lldb.debugger.GetSelectedTarget().FindFirstType("__int128").size 0 (lldb) script lldb.debugger.GetSelectedTarget().FindFirstType("unsigned __int128").size 0 (lldb) quit ``` The value return by the `SBTarget::FindFirstType` method is wrong for the `__int128` and `unsigned __int128` basic types. The proposed changes make the `TypeSystemClang::GetBasicTypeEnumeration` method consistent with `gcc` and `clang` C [language extension](https://gcc.gnu.org/onlinedocs/gcc/_005f_005fint128.html) related to 128-bit integer types as well as with the `BuiltinType::getName` method in the LLVM codebase itself. When the above change is applied, the behavior of the `lldb` changes in the following (desired) way: ``` $ lldb (lldb) target create main Current executable set to '.../main' (x86_64). (lldb) breakpoint set --name main Breakpoint 1: where = main`main + 11 at main.c:2:3, address = 0x000000000022aa7b (lldb) process launch Process 3773637 launched: '/home/me/tmp/built-in/main' (x86_64) Process 3773637 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000000000022aa7b main`main at main.c:2:3 1 int main() { -> 2 return 0; 3 } (lldb) script lldb.debugger.GetSelectedTarget().FindFirstType("__int128").size 16 (lldb) script lldb.debugger.GetSelectedTarget().FindFirstType("unsigned __int128").size 16 (lldb) quit ``` --------- Co-authored-by: Matej Košík <[email protected]>

**Mitigation for:** google/sanitizers#749 **Disclosure:** I'm not an ASan compiler expert yet (I'm trying to learn!), I primarily work in the runtime. Some of this PR was developed with the help of AI tools (primarily as a "fuzzy `grep` engine"), but I've manually refined and tested the output, and can speak for every line. In general, I used it only to orient myself and for "rubberducking". **Context:** The msvc ASan team (👋 ) has received an internal request to improve clang's exception handling under ASan for Windows. Namely, we're interested in **mitigating** this bug: google/sanitizers#749 To summarize, today, clang + ASan produces a false-positive error for this program: ```C++ #include <cstdio> #include <exception> int main() { try { throw std::exception("test"); }catch (const std::exception& ex){ puts(ex.what()); } return 0; } ``` The error reads as such: ``` C:\Users\dajusto\source\repros\upstream>type main.cpp #include <cstdio> #include <exception> int main() { try { throw std::exception("test"); }catch (const std::exception& ex){ puts(ex.what()); } return 0; } C:\Users\dajusto\source\repros\upstream>"C:\Users\dajusto\source\repos\llvm-project\build.runtimes\bin\clang.exe" -fsanitize=address -g -O0 main.cpp C:\Users\dajusto\source\repros\upstream>a.exe ================================================================= ==19112==ERROR: AddressSanitizer: access-violation on unknown address 0x000000000000 (pc 0x7ff72c7c11d9 bp 0x0080000ff960 sp 0x0080000fcf50 T0) ==19112==The signal is caused by a READ memory access. ==19112==Hint: address points to the zero page. #0 0x7ff72c7c11d8 in main C:\Users\dajusto\source\repros\upstream\main.cpp:8 #1 0x7ff72c7d479f in _CallSettingFrame C:\repos\msvc\src\vctools\crt\vcruntime\src\eh\amd64\handlers.asm:49 #2 0x7ff72c7c8944 in __FrameHandler3::CxxCallCatchBlock(struct _EXCEPTION_RECORD *) C:\repos\msvc\src\vctools\crt\vcruntime\src\eh\frame.cpp:1567 swiftlang#3 0x7ffb4a90e3e5 (C:\WINDOWS\SYSTEM32\ntdll.dll+0x18012e3e5) swiftlang#4 0x7ff72c7c1128 in main C:\Users\dajusto\source\repros\upstream\main.cpp:6 swiftlang#5 0x7ff72c7c33db in invoke_main C:\repos\msvc\src\vctools\crt\vcstartup\src\startup\exe_common.inl:78 swiftlang#6 0x7ff72c7c33db in __scrt_common_main_seh C:\repos\msvc\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288 swiftlang#7 0x7ffb49b05c06 (C:\WINDOWS\System32\KERNEL32.DLL+0x180035c06) swiftlang#8 0x7ffb4a8455ef (C:\WINDOWS\SYSTEM32\ntdll.dll+0x1800655ef) ==19112==Register values: rax = 0 rbx = 80000ff8e0 rcx = 27d76d00000 rdx = 80000ff8e0 rdi = 80000fdd50 rsi = 80000ff6a0 rbp = 80000ff960 rsp = 80000fcf50 r8 = 100 r9 = 19930520 r10 = 8000503a90 r11 = 80000fd540 r12 = 80000fd020 r13 = 0 r14 = 80000fdeb8 r15 = 0 AddressSanitizer can not provide additional info. SUMMARY: AddressSanitizer: access-violation C:\Users\dajusto\source\repros\upstream\main.cpp:8 in main ==19112==ABORTING ``` The root of the issue _appears to be_ that ASan's instrumentation is incompatible with Window's assumptions for instantiating `catch`-block's parameters (`ex` in the snippet above). The nitty gritty details are lost on me, but I understand that to make this work without loss of ASan coverage, a "serious" refactoring is needed. In the meantime, users risk false positive errors when pairing ASan + catch-block parameters on Windows. **To mitigate this** I think we should avoid instrumenting catch-block parameters on Windows. It appears to me this is as "simple" as marking catch block parameters as "uninteresting" in `AddressSanitizer::isInterestingAlloca`. My manual tests seem to confirm this. I believe this is strictly better than today's status quo, where the runtime generates false positives. Although we're now explicitly choosing to instrument less, the benefit is that now more programs can run with ASan without _funky_ macros that disable ASan on exception blocks. **This PR:** implements the mitigation above, and creates a simple new test for it. _Thanks!_ --------- Co-authored-by: Antonio Frighetto <[email protected]>

…nteger registers (llvm#163646) Fix the `RegisterValue::SetValueFromData` method so that it works also for 128-bit registers that contain integers. Without this change, the `RegisterValue::SetValueFromData` method does not work correctly for 128-bit registers that contain (signed or unsigned) integers. --- Steps to reproduce the problem: (1) Create a program that writes a 128-bit number to a 128-bit registers `xmm0`. E.g.: ``` #include <stdint.h> int main() { __asm__ volatile ( "pinsrq $0, %[lo], %%xmm0\n\t" // insert low 64 bits "pinsrq $1, %[hi], %%xmm0" // insert high 64 bits : : [lo]"r"(0x7766554433221100), [hi]"r"(0xffeeddccbbaa9988) ); return 0; } ``` (2) Compile this program with LLVM compiler: ``` $ $YOUR/clang -g -o main main.c ``` (3) Modify LLDB so that when it will be reading value from the `xmm0` register, instead of assuming that it is vector register, it will treat it as if it contain an integer. This can be achieved e.g. this way: ``` diff --git a/lldb/source/Utility/RegisterValue.cpp b/lldb/source/Utility/RegisterValue.cpp index 0e99451..a4b51db3e56d 100644 --- a/lldb/source/Utility/RegisterValue.cpp +++ b/lldb/source/Utility/RegisterValue.cpp @@ -188,6 +188,7 @@ Status RegisterValue::SetValueFromData(const RegisterInfo &reg_info, break; case eEncodingUint: case eEncodingSint: + case eEncodingVector: if (reg_info.byte_size == 1) SetUInt8(src.GetMaxU32(&src_offset, src_len)); else if (reg_info.byte_size <= 2) @@ -217,23 +218,6 @@ Status RegisterValue::SetValueFromData(const RegisterInfo &reg_info, else if (reg_info.byte_size == sizeof(long double)) SetLongDouble(src.GetLongDouble(&src_offset)); break; - case eEncodingVector: { - m_type = eTypeBytes; - assert(reg_info.byte_size <= kMaxRegisterByteSize); - buffer.bytes.resize(reg_info.byte_size); - buffer.byte_order = src.GetByteOrder(); - if (src.CopyByteOrderedData( - src_offset, // offset within "src" to start extracting data - src_len, // src length - buffer.bytes.data(), // dst buffer - buffer.bytes.size(), // dst length - buffer.byte_order) == 0) // dst byte order - { - error = Status::FromErrorStringWithFormat( - "failed to copy data for register write of %s", reg_info.name); - return error; - } - } } if (m_type == eTypeInvalid) ``` (4) Rebuild the LLDB. (5) Observe what happens how LLDB will print the content of this register after it was initialized with 128-bit value. ``` $YOUR/lldb --source ./main (lldb) target create main Current executable set to '.../main' (x86_64). (lldb) breakpoint set --file main.c --line 11 Breakpoint 1: where = main`main + 45 at main.c:11:3, address = 0x000000000000164d (lldb) settings set stop-line-count-before 20 (lldb) process launch Process 2568735 launched: '.../main' (x86_64) Process 2568735 stopped * thread #1, name = 'main', stop reason = breakpoint 1.1 frame #0: 0x000055555555564d main`main at main.c:11:3 1 #include <stdint.h> 2 3 int main() { 4 __asm__ volatile ( 5 "pinsrq $0, %[lo], %%xmm0\n\t" // insert low 64 bits 6 "pinsrq $1, %[hi], %%xmm0" // insert high 64 bits 7 : 8 : [lo]"r"(0x7766554433221100), 9 [hi]"r"(0xffeeddccbbaa9988) 10 ); -> 11 return 0; 12 } (lldb) register read --format hex xmm0 xmm0 = 0x7766554433221100ffeeddccbbaa9988 ``` You can see that the upper and lower 64-bit wide halves are swapped. --------- Co-authored-by: Matej Košík <[email protected]>

…lvm#162993) Early if conversion can create instruction sequences such as ``` mov x1, #1 csel x0, x1, x2, eq ``` which could be simplified into the following instead ``` csinc x0, x2, xzr, ne ``` One notable example that generates code like this is `cmpxchg weak`. This is fixed by handling an immediate value of 1 as `add(wzr, 1)` so that the addition can be folded into CSEL by using CSINC instead.

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