Merge llvm-project main llvmorg-18-init-18359-g93248729cfae

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvm-project main llvmorg-18-init-18359-g93248729cfae, the
last commit before the upstream release/18.x branch was created.

PR: 276104
MFC after: 1 month

Merge llvm-project main llvmorg-18-init-16595-g7c00a5be5cde

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvm-project main llvmorg-18-init-16595-g7c00a5be5cde.

PR: 276104
MFC after: 1 month

Merge llvm-project main llvmorg-18-init-15088-gd14ee76181fb

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvm-project main llvmorg-18-init-15088-gd14ee76181fb.

PR: 276104
MFC after: 1 month

Merge llvm-project main llvmorg-17-init-19304-gd0b54bb50e51

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvm-project main llvmorg-17-init-19304-gd0b54bb50e51, the
last commit before the upstream release/17.x branch was created.

PR: 273753
MFC after: 1 month

Merge llvm-project main llvmorg-16-init-18548-gb0daacf58f41

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-16-init-18548-gb0daacf58f41.

PR: 271047
MFC after: 1 month

Merge llvm-project main llvmorg-15-init-17826-g1f8ae9d7e7e4

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-17826-g1f8ae9d7e7e4, the last commit before
the upstream release/16.x branch was created.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-15-init-15358-g53dc0f10787

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-15358-g53dc0f10787.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-18294-gdb01b123d012

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-18294-gdb01b123d012, the last commit before
the upstream release/14.x branch was created.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-17616-g024a1fab5c35

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-17616-g024a1fab5c35.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-13186-g0c553cc1af2e

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-13186-g0c553cc1af2e.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-11187-g222442ec2d71

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-11187-g222442ec2d71.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-10186-gff7f2cfa959b

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-10186-gff7f2cfa959b.

PR: 261742
MFC after: 2 weeks

Merge llvm-project release/13.x llvmorg-13.0.0-rc1-97-g23ba3732246a

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13.0.0-rc1-97-g23ba3732246a.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-13-init-16847-g88e66fa60ae5

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13-init-16847-g88e66fa60ae5, the last commit before
the upstream release/13.x branch was created.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.1-rc2-0-g43ff75f2c3f (aka 11.0.1 rc2).

MFC after: 4 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.0-rc2-91-g6e042866c30.

MFC after: 6 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
master 2e10b7a39b9, the last commit before the llvmorg-12-init tag, from
which release/11.x was branched.

Note that for now, I rolled back all our local changes to make merging
easier, and I will reapply the still-relevant ones after updating to
11.0.0-rc1.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Merge ^/vendor/lvm-project/master up to its last change (upstream commit
e26a78e70), and resolve conflicts.

Merge ^/vendor/lld/dist up to its last change, and resolve conflicts.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Merge llvm-project main llvmorg-17-init-19304-gd0b54bb50e51

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvm-project main llvmorg-17-init-19304-gd0b54bb50e51, the
last commit before the upstream release/17.x branch was created.

PR: 273753
MFC after: 1 month

Merge llvm-project main llvmorg-16-init-18548-gb0daacf58f41

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-16-init-18548-gb0daacf58f41.

PR: 271047
MFC after: 1 month

Merge llvm-project main llvmorg-15-init-17826-g1f8ae9d7e7e4

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-17826-g1f8ae9d7e7e4, the last commit before
the upstream release/16.x branch was created.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-15-init-15358-g53dc0f10787

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-15358-g53dc0f10787.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-18294-gdb01b123d012

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-18294-gdb01b123d012, the last commit before
the upstream release/14.x branch was created.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-17616-g024a1fab5c35

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-17616-g024a1fab5c35.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-13186-g0c553cc1af2e

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-13186-g0c553cc1af2e.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-11187-g222442ec2d71

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-11187-g222442ec2d71.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-10186-gff7f2cfa959b

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-10186-gff7f2cfa959b.

PR: 261742
MFC after: 2 weeks

Merge llvm-project release/13.x llvmorg-13.0.0-rc1-97-g23ba3732246a

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13.0.0-rc1-97-g23ba3732246a.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-13-init-16847-g88e66fa60ae5

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13-init-16847-g88e66fa60ae5, the last commit before
the upstream release/13.x branch was created.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.1-rc2-0-g43ff75f2c3f (aka 11.0.1 rc2).

MFC after: 4 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.0-rc2-91-g6e042866c30.

MFC after: 6 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
master 2e10b7a39b9, the last commit before the llvmorg-12-init tag, from
which release/11.x was branched.

Note that for now, I rolled back all our local changes to make merging
easier, and I will reapply the still-relevant ones after updating to
11.0.0-rc1.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Merge ^/vendor/lvm-project/master up to its last change (upstream commit
e26a78e70), and resolve conflicts.

Merge ^/vendor/lld/dist up to its last change, and resolve conflicts.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Merge llvm-project main llvmorg-16-init-18548-gb0daacf58f41

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-16-init-18548-gb0daacf58f41.

PR: 271047
MFC after: 1 month

Merge llvm-project main llvmorg-15-init-17826-g1f8ae9d7e7e4

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-17826-g1f8ae9d7e7e4, the last commit before
the upstream release/16.x branch was created.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-15-init-15358-g53dc0f10787

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-15358-g53dc0f10787.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-18294-gdb01b123d012

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-18294-gdb01b123d012, the last commit before
the upstream release/14.x branch was created.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-17616-g024a1fab5c35

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-17616-g024a1fab5c35.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-13186-g0c553cc1af2e

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-13186-g0c553cc1af2e.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-11187-g222442ec2d71

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-11187-g222442ec2d71.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-10186-gff7f2cfa959b

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-10186-gff7f2cfa959b.

PR: 261742
MFC after: 2 weeks

Merge llvm-project release/13.x llvmorg-13.0.0-rc1-97-g23ba3732246a

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13.0.0-rc1-97-g23ba3732246a.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-13-init-16847-g88e66fa60ae5

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13-init-16847-g88e66fa60ae5, the last commit before
the upstream release/13.x branch was created.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.1-rc2-0-g43ff75f2c3f (aka 11.0.1 rc2).

MFC after: 4 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.0-rc2-91-g6e042866c30.

MFC after: 6 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
master 2e10b7a39b9, the last commit before the llvmorg-12-init tag, from
which release/11.x was branched.

Note that for now, I rolled back all our local changes to make merging
easier, and I will reapply the still-relevant ones after updating to
11.0.0-rc1.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Merge ^/vendor/lvm-project/master up to its last change (upstream commit
e26a78e70), and resolve conflicts.

Merge ^/vendor/lld/dist up to its last change, and resolve conflicts.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Merge llvm-project main llvmorg-15-init-17826-g1f8ae9d7e7e4

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-17826-g1f8ae9d7e7e4, the last commit before
the upstream release/16.x branch was created.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-15-init-15358-g53dc0f10787

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-15-init-15358-g53dc0f10787.

PR: 265425
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-18294-gdb01b123d012

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-18294-gdb01b123d012, the last commit before
the upstream release/14.x branch was created.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-17616-g024a1fab5c35

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-17616-g024a1fab5c35.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-13186-g0c553cc1af2e

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-13186-g0c553cc1af2e.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-11187-g222442ec2d71

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-11187-g222442ec2d71.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-10186-gff7f2cfa959b

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-10186-gff7f2cfa959b.

PR: 261742
MFC after: 2 weeks

Merge llvm-project release/13.x llvmorg-13.0.0-rc1-97-g23ba3732246a

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13.0.0-rc1-97-g23ba3732246a.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-13-init-16847-g88e66fa60ae5

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13-init-16847-g88e66fa60ae5, the last commit before
the upstream release/13.x branch was created.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.1-rc2-0-g43ff75f2c3f (aka 11.0.1 rc2).

MFC after: 4 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.0-rc2-91-g6e042866c30.

MFC after: 6 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
master 2e10b7a39b9, the last commit before the llvmorg-12-init tag, from
which release/11.x was branched.

Note that for now, I rolled back all our local changes to make merging
easier, and I will reapply the still-relevant ones after updating to
11.0.0-rc1.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Merge ^/vendor/lvm-project/master up to its last change (upstream commit
e26a78e70), and resolve conflicts.

Merge ^/vendor/lld/dist up to its last change, and resolve conflicts.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Merge llvm-project main llvmorg-14-init-18294-gdb01b123d012

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-18294-gdb01b123d012, the last commit before
the upstream release/14.x branch was created.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-17616-g024a1fab5c35

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-17616-g024a1fab5c35.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-13186-g0c553cc1af2e

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-13186-g0c553cc1af2e.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-11187-g222442ec2d71

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-11187-g222442ec2d71.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-14-init-10186-gff7f2cfa959b

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-10186-gff7f2cfa959b.

PR: 261742
MFC after: 2 weeks

Merge llvm-project release/13.x llvmorg-13.0.0-rc1-97-g23ba3732246a

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13.0.0-rc1-97-g23ba3732246a.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-13-init-16847-g88e66fa60ae5

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13-init-16847-g88e66fa60ae5, the last commit before
the upstream release/13.x branch was created.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.1-rc2-0-g43ff75f2c3f (aka 11.0.1 rc2).

MFC after: 4 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.0-rc2-91-g6e042866c30.

MFC after: 6 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
master 2e10b7a39b9, the last commit before the llvmorg-12-init tag, from
which release/11.x was branched.

Note that for now, I rolled back all our local changes to make merging
easier, and I will reapply the still-relevant ones after updating to
11.0.0-rc1.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Merge ^/vendor/lvm-project/master up to its last change (upstream commit
e26a78e70), and resolve conflicts.

Merge ^/vendor/lld/dist up to its last change, and resolve conflicts.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Merge llvm-project release/13.x llvmorg-13.0.0-rc1-97-g23ba3732246a

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13.0.0-rc1-97-g23ba3732246a.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-13-init-16847-g88e66fa60ae5

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-13-init-16847-g88e66fa60ae5, the last commit before
the upstream release/13.x branch was created.

PR: 258209
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.1-rc2-0-g43ff75f2c3f (aka 11.0.1 rc2).

MFC after: 4 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
release/11.x llvmorg-11.0.0-rc2-91-g6e042866c30.

MFC after: 6 weeks
X-MFC-With: r364284

Merge llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and openmp
master 2e10b7a39b9, the last commit before the llvmorg-12-init tag, from
which release/11.x was branched.

Note that for now, I rolled back all our local changes to make merging
easier, and I will reapply the still-relevant ones after updating to
11.0.0-rc1.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Merge ^/vendor/lvm-project/master up to its last change (upstream commit
e26a78e70), and resolve conflicts.

Merge ^/vendor/lld/dist up to its last change, and resolve conflicts.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Revert r357259, after the merge from head which added linker scripts for
stand/i386 boot:

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

Revert upstream lld r371957 (git commit 06bb7dfbd) by Fangrui Song:

[ELF] Map the ELF header at imageBase

If there is no readonly section, we map:

* The ELF header at imageBase+maxPageSize
* Program headers at imageBase+maxPageSize+sizeof(Ehdr)
* The first section .text at imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)

Due to the interaction between Writer<ELFT>::fixSectionAlignments and
LinkerScript::allocateHeaders,
`alignDown(p_vaddr(R PT_LOAD)) = alignDown(p_vaddr(RX PT_LOAD))`.
The RX PT_LOAD will override the R PT_LOAD at runtime, which is not ideal:

```
// PHDR at 0x401034, should be 0x400034
PHDR 0x000034 0x00401034 0x00401034 0x000a0 0x000a0 R 0x4
// R PT_LOAD contains just Ehdr and program headers.
// At 0x401000, should be 0x400000
LOAD 0x000000 0x00401000 0x00401000 0x000d4 0x000d4 R 0x1000
LOAD 0x0000d4 0x004010d4 0x004010d4 0x00001 0x00001 R E 0x1000
```

* createPhdrs allocates the headers to the R PT_LOAD.
* fixSectionAlignments assigns `imageBase+maxPageSize+sizeof(Ehdr)+sizeof(program headers)` (formula: `alignTo(dot, maxPageSize) + dot % config->maxPageSize`) to addrExpr of .text
* allocateHeaders computes the minimum address among SHF_ALLOC sections, i.e. addr(.text)
* allocateHeaders sets address of ELF header to `addr(.text)-sizeof(Ehdr)-sizeof(program headers) = imageBase+maxPageSize`

The main observation is that when the SECTIONS command is not used, we
don't have to call allocateHeaders. This requires an assumption that
the presence of PT_PHDR and addresses of headers can be decided
regardless of address information.

This may seem natural because dot is not manipulated by a linker script.
The other thing is that we have to drop the special rule for -T<section>
in `getInitialDot`. If -Ttext is smaller than the image base, the headers
will not be allocated with the old behavior (allocateHeaders is called)
but always allocated with the new behavior.

The behavior change is not a problem. Whether and where headers are
allocated can vary among linkers, or ld.bfd across different versions
(--enable-separate-code or not). It is thus advised to use a linker
script with the PHDRS command to have a consistent behavior across
linkers. If PT_PHDR is needed, an explicit --image-base can be a simpler
alternative.

Differential Revision: https://reviews.llvm.org/D67325

llvm-svn: 371957

This causes "ld: error: output file too large: 18446744073707016908
bytes" when linking our loader_4th and loader_lua. Clearly, something
is wrong when using -Ttext 0x0: I will file an upstream bug report for
this.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.