[Hexagon] Fix UB from signed left shift overflow in evaluateEXTRACTi (#181243)
The evaluateEXTRACTi function in HexagonConstPropagation uses a left
shift to position a bitfield at the top of a 64-bit word before
extracting it with a right shift. When the source value has high bits
set, the left shift of the int64_t value overflows, which is undefined
behavior.
Fix by performing the left shift in uint64_t, then casting to int64_t
only for the subsequent arithmetic right shift (signed extract case).
[clangd] Guard against null TemplateName in DumpVisitor (#181554)
Add a guard against null values for TemplateName in
DumpVisitor::TraverseTemplateName.
clangd’s DumpVisitor may attempt to traverse a null TemplateName when
handling dependent nested template names. On LLVM main this can lead to
a crash in TemplateName::getKind().
Add a defensive check in DumpVisitor::TraverseTemplateName() to skip
null TemplateName instances before invoking traverseNode(). Following
the same design as other functions in the class.
No functional change is intended beyond preventing the crash.
Fixes: #180902
---------
Signed-off-by: Emily Dror <emilydror01 at gmail.com>
[clang][TypePrinter] Introduce AnonymousTagMode enum (#182317)
As part of https://github.com/llvm/llvm-project/pull/159592, we want to
emit unique lambda names into debug-info without relying on
`AnonymousTagLocations` (i.e., we don't want the source files included
in the names).
The plan is to implement this as a third `AnonymousTagMode`. This patch
turns the existing `AnonymousTagLocations` into an enum as preparation.
(full prototype is at https://github.com/llvm/llvm-project/pull/168533)
[LFI] Add MCLFIRewriter infrastructure (#172906)
This is the second patch in the LFI series, adding the following
features:
* `MCLFIRewriter` class, which will be used to perform LFI rewrites on a
per-architecture basis. Each architecture where LFI is supported will
implement a subclass (for example,
`Target/AArch64/MCTargetDesc/AArch64MCLFIRewriter.cpp`) that will
implement the `rewriteInst` function to perform the actual rewriting
(the AArch64 version will be added in the next PR). The generic rewriter
class provides some instruction info utilities (`mayLoad`, `mayStore`)
and is used to call `rewriteInst` during instruction emission. It also
provides `onLabel` which allows the rewriter to know possible branch
targets, making certain optimizations like guard elimination possible.
* LFI streamer initialization that marks object files with a NOTE
section to indicate that the object file is using LFI.
* A basic LFI assembly parser that introduces the `.lfi_rewrite_disable`
and `.lfi_rewrite_enable` directives that can be used to control whether
rewriting is enabled or not in hand-written assembly.
[RISCV] Correct the LMUL operand for __riscv_sf_vc_i_se_u8mf4 and __riscv_sf_vc_i_se_u8mf2 intrinsics. (#182345)
mf2 is should 7 (-1 in 3 bits). mf4 should be 6 (-2 in 3 bits).
bhyve: fix USB mouse requests
USB HCI requests may not include HCI transfer block structures (i.e.,
xfer->data[] == NULL), but in several places, the USB mouse emulation
code assumes one will exist. This can lead to a NULL pointer dereference
and a SEGV in the bhyve process as observed via experiments with an
Ubuntu guest and PyUSB code. Note that many of the cases processing
other request types already checked for data == NULL.
While in the neighborhood, fix a typo in the loop iterating over the
usb_data_xfer_block array which used the wrong variable to check for
valid data (idx vs. i).
Reported by: danmcd at edgecast.io
Obtained from: SmartOS
MFC after: 1 week
Relnotes: yes
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D54661
[TableGen][ISel] Add OPC_CheckTypeByHwMode0 to optimize the most frequent getValueTypeForHwMode index. (#182366)
Sort the unique ValueTypeByHwMode combinations by usage and add a
compressed opcode for the most common.
Reduces the RISCVGenDAGISel.inc table by about ~12K. The most common
being XLenVT.
I plan to add EmitIntegerByHwMode0 and EmitRegisterByHwMode0 in
subsequent patches.
Assisted-by: claude
[LV] Add tests with predicated early exits.
Add test coverage for predicated early exits, without instructions that
need predication after the early exits.
[Clang] Introduce OverflowBehaviorType for fine-grained overflow control (#148914)
Introduce `OverflowBehaviorType` (OBT), a new type attribute in Clang
that provides developers with fine-grained control over the overflow
behavior of integer types. This feature allows for a more nuanced
approach to integer safety, achieving better granularity than global
compiler flags like `-fwrapv` and `-ftrapv`. Type specifiers are also
available as keywords `__ob_wrap` and `__ob_trap`.
These can be applied to integer types (both signed and unsigned) as well
as typedef declarations, where the behavior is one of the following:
* `wrap`: Guarantees that arithmetic operations on the type will wrap on
overflow, similar to `-fwrapv`. This suppresses UBSan's integer overflow
checks for the attributed type and prevents eager compiler
optimizations.
* `trap`: Enforces overflow checking for the type, even when global
flags like `-fwrapv` would otherwise suppress it.
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