A UD2 might make its way into the program via a call to @llvm.trap.
Obviously, calls are not terminators. However, we modeled the X86
instruction, UD2, as a terminator. Later on, this confuses the epilogue
insertion machinery which results in the epilogue getting inserted
before the UD2. For some platforms, like x64, the result is a
violation of the ABI.
Instead, model UD2/UD2B as a side effecting instruction which may
observe memory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278144 91177308-0d34-0410-b5e6-96231b3b80d8
Their opcodes are used as part of the VEX prefix in 64-bit mode. Clearly the disassembler implicitly decoded them as AVX instructions in 64-bit mode, but I think the AsmParser would have encoded them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258793 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes an issue where MS inline assembly containing xgetbv wouldn't
be marked as clobbering EAX:EDX. Test for that forthcoming on the Clang
side.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217173 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support for a new builtin instruction called
__builtin_ia32_rdpmc.
Builtin '__builtin_ia32_rdpmc' is defined as a 'GCC builtin'; on X86, it can
be used to read performance monitoring counters. It takes as input the index
of the performance counter to read, and returns the value of the specified
performance counter as a 64-bit number.
Calls to this new builtin will map to instruction RDPMC.
The index in input to the builtin call is moved to register %ECX. The result
of the builtin call is the value of the specified performance counter (RDPMC
would return that quantity in registers RDX:RAX).
This patch:
- Adds builtin int_x86_rdpmc as a GCCBuiltin;
- Adds a new x86 DAG node called 'RDPMC_DAG';
- Teaches how to lower this new builtin;
- Adds an ISel pattern to select instruction RDPMC;
- Fixes the definition of instruction RDPMC adding %RAX and %RDX as
implicit definitions, and adding %ECX as implicit use;
- Adds a LLVM test to verify that the new builtin is correctly selected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212049 91177308-0d34-0410-b5e6-96231b3b80d8
This patch:
- Adds two new X86 builtin intrinsics ('int_x86_rdtsc' and
'int_x86_rdtscp') as GCCBuiltin intrinsics;
- Teaches the backend how to lower the two new builtins;
- Introduces a common function to lower READCYCLECOUNTER dag nodes
and the two new rdtsc/rdtscp intrinsics;
- Improves (and extends) the existing x86 test 'rdtsc.ll'; now test 'rdtsc.ll'
correctly verifies that both READCYCLECOUNTER and the two new intrinsics
work fine for both 64bit and 32bit Subtargets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207127 91177308-0d34-0410-b5e6-96231b3b80d8
This avoids miscompiling MS inline asm in LLVM where we have to infer
clobbers. Test case forthcoming in Clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200279 91177308-0d34-0410-b5e6-96231b3b80d8
This should allow SSE instructions to be encoded correctly in 16-bit mode which r198586 probably broke.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199193 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes the bulk of 16-bit output, and the corresponding test case
x86-16.s now looks mostly like the x86-32.s test case that it was
originally based on. A few irrelevant instructions have been dropped,
and there are still some corner cases to be fixed in subsequent patches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198752 91177308-0d34-0410-b5e6-96231b3b80d8
That's what it actually means, and with 16-bit support it's going to be
a little more relevant since in a few corner cases we may actually want
to distinguish between 16-bit and 32-bit mode (for example the bare 'push'
aliases to pushw/pushl etc.)
Patch by David Woodhouse
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197768 91177308-0d34-0410-b5e6-96231b3b80d8
As these two instructions in AVX extension are privileged instructions for
special purpose, it's only expected to be used in inlined assembly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179266 91177308-0d34-0410-b5e6-96231b3b80d8
