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chandlerc
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See #135882 for the introduction of this flag in CMake and TableGen.

Also note that #135882 has been reverted a couple of times -- this should only be merged once it sticks. Let me know @jurahul if you'd like to incorporate this into your PR so it goes in and out together. Otherwise I can just land this once yours is in place.

@llvmbot llvmbot added the bazel "Peripheral" support tier build system: utils/bazel label Apr 17, 2025
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jurahul commented Apr 17, 2025

Thanks. I am still debugging some issues with that PR before it can go in, so I'll incorporate this into the PR when its ready for review.

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jurahul commented Apr 19, 2025

I am attempting to resurrect that change again and have incorporated the bazel build changes there: #136456

jurahul added a commit that referenced this pull request Apr 21, 2025
- Add command line option `num-to-skip-size` to parameterize the size of
`NumToSkip` bytes in the decoder table. Default value will be 2, and
targets that need larger size can use 3.
- Keep all existing targets, except AArch64, to use size 2, and change
AArch64 to use size 3 since it run into the "disassembler decoding table
too large" error with size 2.
- Additional fixes on top of earlier revert: mark `decodeNumToSkip` as
static (not necessary anymore as the generated code is now in anonymous
namespace, but doing it for consistency) and incorporate Bazel build
changes from #136212
- Following is a rough reduction in size for the decoder tables by
switching to size 2.

```
Target         Old Size   New Size   % Reduction
================================================
AArch64           153254     153254        0.00
AMDGPU            471566     412805       12.46
ARC                 5724       5061       11.58
ARM                84936      73831       13.07
AVR                 1497       1306       12.76
BPF                 2172       1927       11.28
CSKY               10064       8692       13.63
Hexagon            47967      41965       12.51
Lanai               1108        982       11.37
LoongArch          24446      21621       11.56
MSP430              4200       3716       11.52
Mips               36330      31415       13.53
PPC                31897      28098       11.91
RISCV              37979      32790       13.66
Sparc               8331       7252       12.95
SystemZ            36722      32248       12.18
VE                 48296      42873       11.23
XCore               2590       2316       10.58
Xtensa              3827       3316       13.35
```
llvm-sync bot pushed a commit to arm/arm-toolchain that referenced this pull request May 6, 2025
…(#136456)

- Add command line option `num-to-skip-size` to parameterize the size of
`NumToSkip` bytes in the decoder table. Default value will be 2, and
targets that need larger size can use 3.
- Keep all existing targets, except AArch64, to use size 2, and change
AArch64 to use size 3 since it run into the "disassembler decoding table
too large" error with size 2.
- Additional fixes on top of earlier revert: mark `decodeNumToSkip` as
static (not necessary anymore as the generated code is now in anonymous
namespace, but doing it for consistency) and incorporate Bazel build
changes from llvm/llvm-project#136212
- Following is a rough reduction in size for the decoder tables by
switching to size 2.

```
Target         Old Size   New Size   % Reduction
================================================
AArch64           153254     153254        0.00
AMDGPU            471566     412805       12.46
ARC                 5724       5061       11.58
ARM                84936      73831       13.07
AVR                 1497       1306       12.76
BPF                 2172       1927       11.28
CSKY               10064       8692       13.63
Hexagon            47967      41965       12.51
Lanai               1108        982       11.37
LoongArch          24446      21621       11.56
MSP430              4200       3716       11.52
Mips               36330      31415       13.53
PPC                31897      28098       11.91
RISCV              37979      32790       13.66
Sparc               8331       7252       12.95
SystemZ            36722      32248       12.18
VE                 48296      42873       11.23
XCore               2590       2316       10.58
Xtensa              3827       3316       13.35
```
IanWood1 pushed a commit to IanWood1/llvm-project that referenced this pull request May 6, 2025
- Add command line option `num-to-skip-size` to parameterize the size of
`NumToSkip` bytes in the decoder table. Default value will be 2, and
targets that need larger size can use 3.
- Keep all existing targets, except AArch64, to use size 2, and change
AArch64 to use size 3 since it run into the "disassembler decoding table
too large" error with size 2.
- Additional fixes on top of earlier revert: mark `decodeNumToSkip` as
static (not necessary anymore as the generated code is now in anonymous
namespace, but doing it for consistency) and incorporate Bazel build
changes from llvm#136212
- Following is a rough reduction in size for the decoder tables by
switching to size 2.

```
Target         Old Size   New Size   % Reduction
================================================
AArch64           153254     153254        0.00
AMDGPU            471566     412805       12.46
ARC                 5724       5061       11.58
ARM                84936      73831       13.07
AVR                 1497       1306       12.76
BPF                 2172       1927       11.28
CSKY               10064       8692       13.63
Hexagon            47967      41965       12.51
Lanai               1108        982       11.37
LoongArch          24446      21621       11.56
MSP430              4200       3716       11.52
Mips               36330      31415       13.53
PPC                31897      28098       11.91
RISCV              37979      32790       13.66
Sparc               8331       7252       12.95
SystemZ            36722      32248       12.18
VE                 48296      42873       11.23
XCore               2590       2316       10.58
Xtensa              3827       3316       13.35
```
IanWood1 pushed a commit to IanWood1/llvm-project that referenced this pull request May 6, 2025
- Add command line option `num-to-skip-size` to parameterize the size of
`NumToSkip` bytes in the decoder table. Default value will be 2, and
targets that need larger size can use 3.
- Keep all existing targets, except AArch64, to use size 2, and change
AArch64 to use size 3 since it run into the "disassembler decoding table
too large" error with size 2.
- Additional fixes on top of earlier revert: mark `decodeNumToSkip` as
static (not necessary anymore as the generated code is now in anonymous
namespace, but doing it for consistency) and incorporate Bazel build
changes from llvm#136212
- Following is a rough reduction in size for the decoder tables by
switching to size 2.

```
Target         Old Size   New Size   % Reduction
================================================
AArch64           153254     153254        0.00
AMDGPU            471566     412805       12.46
ARC                 5724       5061       11.58
ARM                84936      73831       13.07
AVR                 1497       1306       12.76
BPF                 2172       1927       11.28
CSKY               10064       8692       13.63
Hexagon            47967      41965       12.51
Lanai               1108        982       11.37
LoongArch          24446      21621       11.56
MSP430              4200       3716       11.52
Mips               36330      31415       13.53
PPC                31897      28098       11.91
RISCV              37979      32790       13.66
Sparc               8331       7252       12.95
SystemZ            36722      32248       12.18
VE                 48296      42873       11.23
XCore               2590       2316       10.58
Xtensa              3827       3316       13.35
```
IanWood1 pushed a commit to IanWood1/llvm-project that referenced this pull request May 6, 2025
- Add command line option `num-to-skip-size` to parameterize the size of
`NumToSkip` bytes in the decoder table. Default value will be 2, and
targets that need larger size can use 3.
- Keep all existing targets, except AArch64, to use size 2, and change
AArch64 to use size 3 since it run into the "disassembler decoding table
too large" error with size 2.
- Additional fixes on top of earlier revert: mark `decodeNumToSkip` as
static (not necessary anymore as the generated code is now in anonymous
namespace, but doing it for consistency) and incorporate Bazel build
changes from llvm#136212
- Following is a rough reduction in size for the decoder tables by
switching to size 2.

```
Target         Old Size   New Size   % Reduction
================================================
AArch64           153254     153254        0.00
AMDGPU            471566     412805       12.46
ARC                 5724       5061       11.58
ARM                84936      73831       13.07
AVR                 1497       1306       12.76
BPF                 2172       1927       11.28
CSKY               10064       8692       13.63
Hexagon            47967      41965       12.51
Lanai               1108        982       11.37
LoongArch          24446      21621       11.56
MSP430              4200       3716       11.52
Mips               36330      31415       13.53
PPC                31897      28098       11.91
RISCV              37979      32790       13.66
Sparc               8331       7252       12.95
SystemZ            36722      32248       12.18
VE                 48296      42873       11.23
XCore               2590       2316       10.58
Xtensa              3827       3316       13.35
```
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Closing as this has now landed as part of #136456

@chandlerc chandlerc closed this May 13, 2025
@chandlerc chandlerc deleted the fix-bz-aarch64-disasm branch May 13, 2025 14:55
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