Changes

[NFC] [ASTReader] Remove unused variables

[clang] Move the soname declaration in a variable at the top of the file

Currently, it is a bit buried in the file even if this is
pretty important for distro.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D108533

polly: remove the old reference to svn in the doc

[analyzer] Catch leaking stack addresses via stack variables

Not only global variables can hold references to dead stack variables.
Consider this example:

  void write_stack_address_to(char **q) {
    char local;
    *q = &local;
  }

  void test_stack() {
    char *p;
    write_stack_address_to(&p);
  }

The address of 'local' is assigned to 'p', which becomes a dangling
pointer after 'write_stack_address_to()' returns.

The StackAddrEscapeChecker was looking for bindings in the store which
referred to variables of the popped stack frame, but it only considered
global variables in this regard. This patch relaxes this, catching
stack variable bindings as well.

---

This patch also works for temporary objects like:

  struct Bar {
    const int &ref;
    explicit Bar(int y) : ref(y) {
      // Okay.
    } // End of the constructor call, `ref` is dangling now. Warning!
  };

  void test() {
    Bar{33}; // Temporary object, so the corresponding memregion is
             // *not* a VarRegion.
  }

---

The return value optimization aka. copy-elision might kick in but that
is modeled by passing an imaginary CXXThisRegion which refers to the
parent stack frame which is supposed to be the 'return slot'.
Objects residing in the 'return slot' outlive the scope of the inner
call, thus we should expect no warning about them - except if we
explicitly disable copy-elision.

Reviewed By: NoQ, martong

Differential Revision: https://reviews.llvm.org/D107078

[docs] Add DIA register instructions to Getting Started with Visual Studio page

Since Visual Studio 2017 the DIA libs are not registered by default, see:
https://docs.microsoft.com/en-us/visualstudio/extensibility/breaking-changes-2017?view=vs-2019#change-reduce-registry-impact
LLDB building instruction already specify registering these DLLs, required
both the LLVM PDB tests and LLDB build.

Differential Revision: https://reviews.llvm.org/D108811

[NFC][X86][MCA] AMD Zen 3: improve MULX test coverage

Latency for MULX isn't right

[X86] AMD Zen 3: MULX produces low part of the result in 3cy, +1cy for high part

As per llvm-exegesis measurements.

[X86] AMD Zen 3: MULX w/ mem operand has the same throughput as with reg op

Exegesis is faulty and sometimes when measuring throughput^-1
produces snippets that have loop-carried dependencies,
which must be what caused me to incorrectly measure it originally.

After looking much more carefully, the inverse throughput should match
that of the MULX w/ reg op.

As per llvm-exegesis measurements.

[M68k] Update pointer data layout

Fixes PR51626.

The M68k requires that all instruction, word and long word reads are
aligned to word boundaries. From the 68020 onwards, there is a
performance benefit from aligning long words to long word boundaries.

The M68k uses the same data layout for pointers and integers.

In line with this, this commit updates the pointer data layout to
match the layout already set for 32-bit integers: 32:16:32.

Differential Revision: https://reviews.llvm.org/D108792

[DAGCombine] Allow FMA combine with both FMA and FMAD

Without this change only the preferred fusion opcode is tested
when attempting to combine FMA operations.
If both FMA and FMAD are available then FMA ops formed prior to
legalization will not be merged post legalization as FMAD becomes
the preferred fusion opcode.

Reviewed By: foad

Differential Revision: https://reviews.llvm.org/D108619

[NFC][X86] Sret return register cleanup

There are no paths into LowerFormalParms that have already specified
the sret register. We always materialize a virtual and then assign it
to the physical reg at the point of the return.

Differential Revision: https://reviews.llvm.org/D108762

[X86] Implement llvm.isnan(x86_fp80) as unordered comparison

x86_fp80 format allows values that do not fit any of IEEE-754 category.
Previously they were recognized by intrinsic __builtin_isnan as NaNs.
Now this intrinsic is implemented using instruction FXAM, which
distinguish between NaNs and unsupported values. It can make some
programs behave differently.

As a solution, this fix changes lowering of the intrinsic. If floating
point exceptions are ignored, llvm.isnan is lowered into unordered
comparison, as __buildtin_isnan was implemented earlier. In strictfp
functions the intrinsic is lowered using FXAM, which does not raise
exceptions even for signaling NaN, as required by IEEE-754 and C
standards.

Differential Revision: https://reviews.llvm.org/D108037

[openmp][amdgpu] Initial gfx10 offloading implementation

Lets wavefront size be 32 for amdgpu openmp, as well as 64.

Fixes up as little as possible to pass that through the libraries. This change
is end to end, as opposed to updating clang/devicertl/plugin separately. It can
be broken up for review/commit if preferred. Posting as-is so that others with
a gfx10 can try it out. It works roughly as well as gfx9 for me, but there are
probably bugs remaining as well as the todo: for letting grid values vary more.

Reviewed By: ronlieb

Differential Revision: https://reviews.llvm.org/D108708

 [MCA][NFC] Removed unused method, and fixed a coverity issue.

The coverity issue was reported agaist class MCAOperand
due to the lack of proper initialization for field Index.

No functional change intended.

[AArch64][SVE] Use getPTrue uniformly.NFC.

[AArch64][SVE] Add API for conversion between SVE predicate pattern and element number. NFC

This patch solely moves convert operation between SVE predicate pattern
and element number into two small functions. It's pre-commit patch for optimize
pture with known sve register width.

Differential Revision: https://reviews.llvm.org/D108705

[AArch64][SVE] Optimize ptrue predicate pattern with known sve register width.

For vectors that are exactly equal to getMaxSVEVectorSizeInBits, just use
AArch64SVEPredPattern::all, which can enable the use of unpredicated ptrue when available.

TestPlan: check-llvm

Differential Revision: https://reviews.llvm.org/D108706

[GlobalOpt] don't hoist constant expressions that can trap

We try to forward a stored-once-constant-value from one global access
to another, but that's not safe if the constant value is an expression
that can trap.

The tests are reduced from the miscompile examples in:
https://llvm.org/PR47578

Differential Revision: https://reviews.llvm.org/D108771

[analyzer] MallocOverflow should consider comparisons only preceding malloc

MallocOverflow works in two phases:

1) Collects suspicious malloc calls, whose argument is a multiplication
2) Filters the aggregated list of suspicious malloc calls by iterating
   over the BasicBlocks of the CFG looking for comparison binary
   operators over the variable constituting in any suspicious malloc.

Consequently, it suppressed true-positive cases when the comparison
check was after the malloc call.
In this patch the checker will consider the relative position of the
relation check to the malloc call.

E.g.:

```lang=C++
void *check_after_malloc(int n, int x) {
  int *p = NULL;
  if (x == 42)
    p = malloc(n * sizeof(int)); // Previously **no** warning, now it
                                 // warns about this.

  // The check is after the allocation!
  if (n > 10) {
    // Do something conditionally.
  }
  return p;
}
```

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D107804

[lld/COFF] Use P_priv more

P_priv does the same as the old QF further down. Standardize on P_priv.

No behavior change.

Differential Revision: https://reviews.llvm.org/D108798

[lld/COFF] Ignore /LTCG, /LTCG:, /LTCGOUT:, /ILK: flags

We currently complain "could not open /LTCG: no such file or directory",
which isn't very useful.  We could emit a warning when we see this flag, but
just ignoring it seems fine.

Final missing part of PR38799.

Differential Revision: https://reviews.llvm.org/D108799

GlobalISel: Remove check for empty functions as these are invalid IR

[clang-format] Group options that pack constructor initializers

Add a new option PackConstructorInitializers and deprecate the
related options ConstructorInitializerAllOnOneLineOrOnePerLine and
AllowAllConstructorInitializersOnNextLine. Below is the mapping:

PackConstructorInitializers  ConstructorInitializer... AllowAll...
        Never                            -                  -
        BinPack                        false                -
        CurrentLine                    true               false
        NextLine                       true               true

The option value Never fixes PR50549 by always placing each
constructor initializer on its own line.

Differential Revision: https://reviews.llvm.org/D108752

Revert "[CMake] Enable LLVM_ENABLE_PER_TARGET_RUNTIME_DIR by default on Linux"

This reverts commit abb956370ee71d018e9a88ae196f039f6c4e0dae, which broke
the libc++ CI on Linux.

[libc++][NFC] Remove extra __ranges/take_view.h entry in CMakeLists.txt

Differential Revision: https://reviews.llvm.org/D108802

[AMDGPU][MC][NFC][DOC] Updated AMD GPU assembler syntax description.

Summary of changes:
- Added f16 omod modifier (bug 51386).
- Corrected names of data types (bug 48638).
- Enabled a16 with most GFX10 MIMG opcodes (see https://reviews.llvm.org/D102231).
- Corrected description of integer operands (bug 51130).
- Corrected description of 8-bit DS offsets (bug 51536).
- Improved PERMLANE op_sel description.
- Corrected *SAD* opcode types.

[IR] Remove getWithOperandReplaced (NFC)

The function hasn't been used for at least 10 years.

[MCParser][z/OS] Mark test as unsupported for the z/OS Target

Marking test as unsupported for the same reason as https://reviews.llvm.org/D105204

Reviewed By: abhina.sreeskantharajan

Differential Revision: https://reviews.llvm.org/D108819

[libc++][NFC] Remove unused helper function in the test suite

[gn build] Don't copy xray includes

The gn build doesn't support xray, so there's no reason to make the xray
headers available. Some CMake checks check if xray includes are
available to determine if xray is usable. Since we don't build the xray
runtime, there are link errors.

Reviewed By: thakis

Differential Revision: https://reviews.llvm.org/D108737

[MC] Change ELFOSABI_NONE to ELFOSABI_GNU for STB_GNU_UNIQUE

Similar to D97976.
On Linux, most GCC installations are configured with
`--enable-gnu-unique-object` and such GCC emits `@gnu_unique_object` assembly.

The feature is highly controversial and disliked by many folks.
(On glibc DF_1_NODELETE is implicitly enabled and makes dlclose a no-op).

In llvm-project STB_GNU_UNIQUE is assembly only. Clang does not use STB_GNU_UNIQUE.

Use ELFOSABI_GNU to match GNU as behavior and avoid collision with other
OSABI binding values.

Reviewed By: jrtc27

Differential Revision: https://reviews.llvm.org/D107861

[libc][Obvious] Add header guards for the generated linux syscall header file.

[trace] [intel pt] Create a "process trace save" command

added new command "process trace save -d <directory>".
-it saves a JSON file as <directory>/trace.json, with the main properties of the trace session.
-it saves binary Intel-pt trace as <directory>/thread_id.trace; each file saves each thread.
-it saves modules to the directory <directory>/modules .
-it only works for live process and it only support Intel-pt right now.

Example:
```
b main
run
process trace start
n
process trace save -d /tmp/mytrace
```
A file named trace.json and xxx.trace should be generated in /tmp/mytrace. To load the trace that was just saved:
```
trace load /tmp/mytrace
thread trace dump instructions
```
You should see the instructions of the trace got printed.

To run a test:
```
cd ~/llvm-sand/build/Release/fbcode-x86_64/toolchain
ninja lldb-dotest
./bin/lldb-dotest -p TestTraceSave
```

Reviewed By: wallace

Differential Revision: https://reviews.llvm.org/D107669

[libc++][NFC] Remove useless _LIBCPP_PUSH_MACROS

Only files that actually use min/max are required to do this dance.

Differential Revision: https://reviews.llvm.org/D108778

[libc++][NFC] Fix include guard for decay_copy.h and remove underscores from the header

We don't use double underscores for private header names when they are
in a subdirectory with double underscores already.

Differential Revision: https://reviews.llvm.org/D108820

[gn build] Port c8b14c03ec74

[test] exercise breakLoopBackedge with a switch latch cond

This was reduced from a test case which triggered a revert to my recent change to same function.  It turns out we didn't have *any* coverage of the non-branch latch and my patch was blatantly broken.

[libcxx] Use GetSystemTimePreciseAsFileTime() if available

We will try to use GetSystemTimePreciseAsFileTime if possible.
Reference: https://sourceforge.net/p/mingw-w64/mingw-w64/ci/59195b2d7fe26549f70969b0dd487293819f023e/.

Reviewed By: compnerd, #libc, mstorsjo, ldionne

Differential Revision: https://reviews.llvm.org/D104987

[RISCV] Add -riscv-v-fixed-length-vector-elen-max to limit the ELEN used for fixed length vectorization.

This adds an ELEN limit for fixed length vectors. This will scalarize
any elements larger than this. It will also disable some fractional
LMULs. For example, if ELEN=32 then mf8 becomes illegal, i32/f32
vectors can't use any fractional LMULs, i16/f16 can only use mf2,
and i8 can use mf2 and mf4.

We may also need something for the scalable vectors, but that has
interactions with the intrinsics and we can't scalarize a scalable
vector.

Longer term this should come from one of the Zve* features

[MC][RISCV] Add RISCV MCObjectFileInfo

This makes sure, that the text section will have a 2-byte alignment, if
the +c extension is enabled.

Reviewed By: MaskRay, luismarques

Differential Revision: https://reviews.llvm.org/D102052

[Codegen][X86] EltsFromConsecutiveLoads(): if only have AVX1, ensure that the "load" is actually foldable (PR51615)

This fixes another reproducer from https://bugs.llvm.org/show_bug.cgi?id=51615
And again, the fix lies not in the code added in D105390

In this case, we completely don't check that the "broadcast-from-mem" we create
can actually fold the load. In this case, it's operand was not a load at all:
```
Combining: t16: v8i32 = vector_shuffle<0,u,u,u,0,u,u,u> t14, undef:v8i32
Creating new node: t29: i32 = undef
RepeatLoad:
t8: i32 = truncate t7
  t7: i64 = extract_vector_elt t5, Constant:i64<0>
    t5: v2i64,ch = load<(load (s128) from %ir.arg)> t0, t2, undef:i64
      t2: i64,ch = CopyFromReg t0, Register:i64 %0
        t1: i64 = Register %0
      t4: i64 = undef
    t3: i64 = Constant<0>
Combining: t15: v8i32 = undef

```

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D108821

Special case common branch patterns in breakLoopBackedge (try 2)

Changes since aec08e:
* Adjust placement of a closing brace so that the general case actually runs.  Turns out we had *no* coverage of the switch case.  I added one in eae90fd.
* Drop .llvm.loop.* metadata from the new branch as there is no longer a loop to annotate.

Original commit message:

This special cases an unconditional latch and a conditional branch latch exit to improve codegen and test readability. I am hoping to reuse this function in the runtime unroll code, but without this change, the test diffs are far too complex to assess.

[gn build] Port 54e8cae56529

Fix assertion when passing function into inline asm's input operand

This seem to be a regression caused by this change:
https://reviews.llvm.org/D60943.
Since we delayed report the error, we would run into some invalid
state in clang and llvm.

Without this fix, clang would assert when passing function into
inline asm's input operand.

Differential Revision: https://reviews.llvm.org/D107941

[Attributor][FIX] Do not treat byval args as local memory (for now)

For now we do should not treat byval arguments as local copies performed
on the call edge, though, in general we should. To make that happen we
need to teach various passes, e.g., DSE, about the copy effect of a
byval. That would also allow us to mark functions only accessing byval
arguments as readnone again, atguably their acceses have no effect
outside of the function, like accesses to allocas.

Reviewed By: kuter

Differential Revision: https://reviews.llvm.org/D108140

[Attributor][FIX] Recursion via memory needs to be tracked explicitly

Recursion can happen when we see a PHI use the second time or when we
look at a store value operand use again. We already visited the
potential copies and doing so again will just cause endless looping.

Reviewed By: kuter

Differential Revision: https://reviews.llvm.org/D108190

[OpenMP][FIX] Allow declare variant to work with reference types

Reference types in the return or parameter position did cause the OpenMP
declare variant overload reasoning to give up. We should allow them as
we allow any other type.

This should fix the bug reported on the mailing list:
https://lists.llvm.org/pipermail/openmp-dev/2021-August/004094.html

Reviewed By: ABataev, pdhaliwal

Differential Revision: https://reviews.llvm.org/D108774

[clang-format] [PR51640] - New AfterEnum brace wrapping changes have cause C# behaviour to change

LLVM 13.0.0-rc2 shows change of behaviour in enum and interface BraceWrapping (likely before we simply didn't wrap)  but may be related to {D99840}

Logged as https://bugs.llvm.org/show_bug.cgi?id=51640

This change ensure AfterEnum works for

`internal|public|protected|private enum A {`  in the same way as it works for `enum A {` in C++

A similar issue was also observed with `interface` in C#

Reviewed By: krasimir, owenpan

Differential Revision: https://reviews.llvm.org/D108810

[ifs] Add option to hide undefined symbols

This change add an option to llvm-ifs to hide undefined symbols from
its output.

Differential Revision: https://reviews.llvm.org/D108428

[test] More test precommits for D108734

[llvm] [lit] Support forcing lexical test order

Add a new --order option to choose between available test orders:
the default "smart" order, predictable "lexical" order or "random"
order.  Default to using lexical order and one job in the lit test
suite.

Differential Revision: https://reviews.llvm.org/D107695

[RISCV] Use ~0ULL instead of ~0U when checking for invalid ErrorInfo.

ErrorInfo is a uint64_t and is initialized to all 1s.

Not sure how to test this. Noticed while working on .insn support.

Use std::less instead of operator < in less_first and less_second

According to the standard, if p1 and p2 are both pointers, p1 < p2 and
p2 < p1 can both be false in theory in some cases:

https://eel.is/c++draft/expr.rel#4.3

std::less<void> yields a implementation-defined strict total order over
pointers:

https://eel.is/c++draft/comparisons.general

Differential Revision: https://reviews.llvm.org/D108733

[Profile] Support __llvm_profile_set_file_object in continuous mode.

Replace D107203, because __llvm_profile_set_file_object is usually used when the
process doesn't have permission to open/create file. That patch trying to copy
from old profile to new profile contradicts with the usage.

Differential Revision: https://reviews.llvm.org/D108242

[MergeICmps] Don't merge icmps derived from pointers with addressspaces

IIUC we can't emit `memcmp` between pointers in addressspaces,
doing so will trigger an assertion since the signature of the memcmp
will not match it's arguments (https://bugs.llvm.org/show_bug.cgi?id=48661).

This PR disables the attempt to merge icmps,
when the pointer is in an addressspace.

Reviewed By: #julialang, vtjnash

Differential Revision: https://reviews.llvm.org/D94813

[test] Precommit test for D108837

Support LLVM_ENABLE_PER_TARGET_RUNTIME_DIR in the sanitizer symbolizer build.

In this mode libc++ headers end up in two directories:
* include/<triple>/c++/v1 for the site config header
* include/c++/v1 for everything else

Also switch from -I to -isystem.

Differential Revision: https://reviews.llvm.org/D108841

[libc] Fix various -Wconversion warnings in strto*l test code.

The Fuchsia build compiles the libc and test code with lots
of warnings enabled, including all the integer conversion warnings.
There was some sloppy type usage here that triggered some of those.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D108800

[libc][NFC] Fix onre more -Wconversion warning in strtoul test code.

The last change missed one spot.

Differential Revision: https://reviews.llvm.org/D108845

[lld/test/ELF] Test fetch from archive to resolve undefined symbols in shared libs

Add missing test coverage uncovered in review of D108006.

Differential Revision: https://reviews.llvm.org/D108328

[LoopDeletion] Use max trip count to break backedge in addition to exact one

We'd added support a while back from breaking the backedge if SCEV can prove the trip count is zero. However, we used the exact trip count which requires *all* exits be analyzeable. I noticed while writing test cases for another patch that this disallows cases where one exit is provably taken paired with another which is unknown. This patch adds the upper bound case.

We could use a symbolic max trip count here instead, but we use an isKnownNonZero filter (presumably for compile time?) for the first-iteration reasoning. I decided this was a more obvious incremental step, and we could go back and untangle the schemes separately.

Differential Revision: https://reviews.llvm.org/D108833

[clang-format] [NFC] Fix the coding style of unit tests header file

[MergeICmps] Ignore clobbering instructions before the loads

This is another followup to D106591. Even if there is an
instruction that clobbers one of the loads, this doesn't matter if
it happens before the loads. Those instructions aren't affected by
the transform at all.

The gep-references-bb.ll is modified to preserve the spirit of the
test, as the store to @g no longer impacts the transform.

Differential Revision: https://reviews.llvm.org/D108782

[Attributor][NFC] Silence unused variable warning

[clang-format] Fix AllowAllConstructorInitializersOnNextLine value

The default value of the now deprecated
AllowAllConstructorInitializersOnNextLine was always true
regardless of the value of BasedOnStyle. This patch fixes the typo
in the code that handles the related backward compatibility.

[IRSim][IROutliner] Canonicalizing commutative value numbering between similarity sections.

When the initial relationship between two pairs of values between
similar sections is ambiguous to commutativity, arguments to the
outlined functions can be passed in such that the order is incorrect,
causing miscompilations.  This adds a canonical mapping to each
similarity section, so that we can maintain the relationship of global
value numbering from one section to another.

Added Tests:
Transforms/IROutliner/outlining-commutative-operands-opposite-order.ll
unittests/Analysis/IRSimilarityIdentifierTest.cpp - IRSimilarityCandidate:CanonicalNumbering

Reviewers: jroelofs, jpaquette, yroux

Differential Revision: https://reviews.llvm.org/D104143

[mlir][sparse] fully implement sparse tensor to sparse tensor conversions

with rigorous integration test

Reviewed By: bixia

Differential Revision: https://reviews.llvm.org/D108721

[ARMISelLowering] avoid emitting libcalls to __mulodi4()

__has_builtin(__builtin_mul_overflow) returns true for 32b ARM targets,
but Clang is deferring to compiler RT when encountering `long long`
types. This breaks sanitizer builds of the Linux kernel that are using
__builtin_mul_overflow with these types for these targets.

If the semantics of __has_builtin mean "the compiler resolves these,
always" then we shouldn't conditionally emit a libcall.

This will still need to be worked around in the Linux kernel in order to
continue to support allmodconfig builds of the Linux kernel for this
target with older releases of clang.

Link: https://bugs.llvm.org/show_bug.cgi?id=28629
Link: https://github.com/ClangBuiltLinux/linux/issues/1438

Reviewed By: rengolin

Differential Revision: https://reviews.llvm.org/D108842

[MipsISelLowering] avoid emitting libcalls to __mulodi4()

__has_builtin(__builtin_mul_overflow) returns true for 32b MIPS targets,
but Clang is deferring to compiler RT when encountering `long long`
types. This breaks sanitizer builds of the Linux kernel that are using
__builtin_mul_overflow with these types for these targets.

If the semantics of __has_builtin mean "the compiler resolves these,
always" then we shouldn't conditionally emit a libcall.

This will still need to be worked around in the Linux kernel in order to
continue to support malta_defconfig builds of the Linux kernel for this
target with older releases of clang.

Link: https://bugs.llvm.org/show_bug.cgi?id=28629
Link: https://github.com/ClangBuiltLinux/linux/issues/1438

Reviewed By: rengolin

Differential Revision: https://reviews.llvm.org/D108844

[compiler-rt] fix real strlens that were missed

In reviews.llvm.org/D108316 I missed a few instances of REAL(strlen) and
this change fixes that, as well as restoring one that seems like it
shouldn't have been changed.

Reviewed By: hctim, vitalybuka

Differential Revision: https://reviews.llvm.org/D108843

[compiler-rt][obvious] fix typo, delete paren

I should've deleted a parenthesis on line 4222 in
https://reviews.llvm.org/D108843 and this patch fixes it.

Differential Revision: https://reviews.llvm.org/D108852

[Sanitizers] wordexp interceptor build fix on FreeBSD.

Reviewers: vitalybuka

Reviewed-By: vitalybuka

Differential Revision: https://reviews.llvm.org/D108838

Specify argument to be `const` for `debugString()` helper (NFC)

This allows using this helper with rvalues.

TypePrinter:printTo remove redundant parameter (IsPack/SkipBrackets)

Use a universal reference (&& instead of const &) for `debugString()` helper (NFC)

Some classes like mlir::Operation have a non-const print() method.

Remove `const` from `const T &&` in debugString() helper to make it a universal reference (NFC)

It broke lvalue arguments otherwise:

[Modules] Change result of reading AST block to llvm::Error instead

Reading the AST block can never fail with a recoverable error as modules
cannot be removed during this phase. Change the return type of these
functions to return an llvm::Error instead, ie. either success or
failure.

NFC other than the wording of some of the errors.

Differential Revision: https://reviews.llvm.org/D108268

[lld/mac] Don't assert on -dead_strip + arm64 range extension thunks

The assert is harmless and thinks worked fine in builds with asserts enabled,
but it's still nice to fix the assert.

Differential Revision: https://reviews.llvm.org/D108853

[JITLink][RISCV] Support GOT/PLT relocations

This patch add the R_RISCV_GOT_HI20 and R_RISCV_CALL_PLT relocation support. And the basic got/plt was implemented. Because of riscv32 and riscv64 has different pointer size, the got entry size and instructions of plt entry is different. This patch is the basic support, the optimization pass at preFixup stage has not been implemented.

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D107688