[libc][i386] syscall support

[nickdesaulniers]

Link: #93709

[llvmbot]

@llvm/pr-subscribers-libc

Author: Nick Desaulniers (nickdesaulniers)

Changes

Link: #93709

---

Full diff: https://github.com/llvm/llvm-project/pull/114264.diff

2 Files Affected:

• (added) libc/src/__support/OSUtil/linux/i386/syscall.h (+76)
• (modified) libc/src/__support/OSUtil/linux/syscall.h (+3-1)

diff --git a/libc/src/__support/OSUtil/linux/i386/syscall.h b/libc/src/__support/OSUtil/linux/i386/syscall.h
new file mode 100644
index 00000000000000..ddc51c543077ed
--- /dev/null
+++ b/libc/src/__support/OSUtil/linux/i386/syscall.h
@@ -0,0 +1,76 @@
+//===---------- inline implementation of i386 syscalls ------------* C++ *-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_I386_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_I386_SYSCALL_H
+
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE {
+
+LIBC_INLINE long syscall_impl(long num) {
+  long ret;
+  LIBC_INLINE_ASM("int $128" : "=a"(ret) : "a"(num) : "memory");
+  return ret;
+}
+
+LIBC_INLINE long syscall_impl(long num, long arg1) {
+  long ret;
+  LIBC_INLINE_ASM("int $128" : "=a"(ret) : "a"(num), "b"(arg1) : "memory");
+  return ret;
+}
+
+LIBC_INLINE long syscall_impl(long num, long arg1, long arg2) {
+  long ret;
+  LIBC_INLINE_ASM("int $128" : "=a"(ret) : "a"(num), "b"(arg1),
+                  "c"(arg2) : "memory");
+  return ret;
+}
+
+LIBC_INLINE long syscall_impl(long num, long arg1, long arg2, long arg3) {
+  long ret;
+  LIBC_INLINE_ASM("int $128" : "=a"(ret) : "a"(num), "b"(arg1), "c"(arg2),
+                  "d"(arg3) : "memory");
+  return ret;
+}
+
+LIBC_INLINE long syscall_impl(long num, long arg1, long arg2, long arg3,
+                              long arg4) {
+  long ret;
+  LIBC_INLINE_ASM("int $128" : "=a"(ret) : "a"(num), "b"(arg1), "c"(arg2),
+                  "d"(arg3), "S"(arg4) : "memory");
+  return ret;
+}
+
+LIBC_INLINE long syscall_impl(long num, long arg1, long arg2, long arg3,
+                              long arg4, long arg5) {
+  long ret;
+  LIBC_INLINE_ASM("int $128" : "=a"(ret) : "a"(num), "b"(arg1), "c"(arg2),
+                  "d"(arg3), "S"(arg4), "D"(arg5) : "memory");
+  return ret;
+}
+
+LIBC_INLINE long syscall_impl(long num, long arg1, long arg2, long arg3,
+                              long arg4, long arg5, long arg6) {
+  long ret;
+  LIBC_INLINE_ASM(R"(
+    push %[arg6]
+    push %%ebp
+    mov 4(%%esp), %%ebp
+    int $128
+    pop %%ebp
+    add $4, %%esp
+  )" : "=a"(ret) : "a"(num),
+                  "b"(arg1), "c"(arg2), "d"(arg3), "S"(arg4),
+                  "D"(arg5), [arg6] "m"(arg6) : "memory");
+  return ret;
+}
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_I386_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/linux/syscall.h b/libc/src/__support/OSUtil/linux/syscall.h
index ad3f6947d0a06a..24e0fca73c1678 100644
--- a/libc/src/__support/OSUtil/linux/syscall.h
+++ b/libc/src/__support/OSUtil/linux/syscall.h
@@ -14,7 +14,9 @@
 #include "src/__support/macros/config.h"
 #include "src/__support/macros/properties/architectures.h"
 
-#ifdef LIBC_TARGET_ARCH_IS_X86_64
+#ifdef LIBC_TARGET_ARCH_IS_X86_32
+#include "i386/syscall.h"
+#elif defined(LIBC_TARGET_ARCH_IS_X86_64)
 #include "x86_64/syscall.h"
 #elif defined(LIBC_TARGET_ARCH_IS_AARCH64)
 #include "aarch64/syscall.h"

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[llvm-ci]

LLVM Buildbot has detected a new failure on builder openmp-offload-libc-amdgpu-runtime running on omp-vega20-1 while building libc at step 11 "Add check check-libc-amdgcn-amd-amdhsa".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/73/builds/7852

Here is the relevant piece of the build log for the reference

Step 11 (Add check check-libc-amdgcn-amd-amdhsa) failure: 1200 seconds without output running [b'ninja', b'-j 32', b'check-libc-amdgcn-amd-amdhsa'], attempting to kill
...
[2555/2681] Linking CXX executable libc/test/src/string/libc.test.src.string.memcmp_test.__hermetic__.__build__
[2556/2681] Linking CXX executable libc/test/src/stdlib/libc.test.src.stdlib.strtof_test.__hermetic__.__build__
[2557/2681] Linking CXX executable libc/test/src/string/libc.test.src.string.strncat_test.__hermetic__.__build__
[2558/2681] Linking CXX executable libc/test/src/string/libc.test.src.string.memmove_test.__hermetic__.__build__
[2559/2681] Linking CXX executable libc/test/src/string/libc.test.src.string.strxfrm_test.__hermetic__.__build__
[2560/2681] Linking CXX executable libc/test/src/inttypes/libc.test.src.inttypes.strtoimax_test.__hermetic__.__build__
[2561/2681] Linking CXX executable libc/test/src/string/libc.test.src.string.strlcat_test.__hermetic__.__build__
[2562/2681] Linking CXX executable libc/test/src/time/libc.test.src.time.clock_gettime_test.__hermetic__.__build__
[2563/2681] Linking CXX executable libc/test/src/stdio/libc.test.src.stdio.vasprintf_test.__hermetic__.__build__
[2564/2681] Linking CXX executable libc/test/src/stdio/libc.test.src.stdio.asprintf_test.__hermetic__.__build__
command timed out: 1200 seconds without output running [b'ninja', b'-j 32', b'check-libc-amdgcn-amd-amdhsa'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1470.388382