| commit | 84f3a4c19a17256a66e00ea94232b2004c3eeaf8 | [log] [tgz] |
|---|---|---|
| author | David Spickett <david.spickett@linaro.org> | Tue Feb 13 10:38:38 2024 +0000 |
| committer | Copybara-Service <copybara-worker@google.com> | Tue Feb 13 02:45:15 2024 -0800 |
| tree | fc4cc6a60966ce9101fed19476c2f5cf86914e05 | |
| parent | 0902ffab88b2bf8b4b642eac4f35cc080c8481f4 [diff] |
[flang][Driver] Add -masm option to flang (#81490)
The motivation here was a suggestion over in Compiler Explorer. You can
use `-mllvm` already to do this but since gfortran supports `-masm`, I
figured I'd try to add it.
This is done by flang expanding `-masm` into `-mllvm x86-asm-syntax=`,
then passing that to fc1. Which then collects all the `-mllvm` options
and forwards them on.
The code to expand it comes from clang `Clang::AddX86TargetArgs` (there
are some other places doing the same thing too). However I've removed
the `-inline-asm` that clang adds, as fortran doesn't have inline
assembly.
So `-masm` for flang purely changes the style of assembly output.
```
$ ./bin/flang-new /tmp/test.f90 -o - -S -target x86_64-linux-gnu
<...>
pushq %rbp
$ ./bin/flang-new /tmp/test.f90 -o - -S -target x86_64-linux-gnu -masm=att
<...>
pushq %rbp
$ ./bin/flang-new /tmp/test.f90 -o - -S -target x86_64-linux-gnu -masm=intel
<...>
push rbp
```
The test is adapted from `clang/test/Driver/masm.c` by removing the
clang-cl related lines and changing the 32 bit triples to 64 bit triples
since flang doesn't support 32 bit targets.
GitOrigin-RevId: 9ca1a1575a337931d0e49859f83a0d5b70916abd
Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.
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