[libc-commits] [libc] 4c810ec - [libc] Add arm-32 syscall implementation.
Siva Chandra Reddy via libc-commits
libc-commits at lists.llvm.org
Wed Aug 31 11:11:01 PDT 2022
Author: Siva Chandra Reddy
Date: 2022-08-31T18:10:40Z
New Revision: 4c810ecb68ef8e9090abd1927ec7262b35005ee7
URL: https://github.com/llvm/llvm-project/commit/4c810ecb68ef8e9090abd1927ec7262b35005ee7
DIFF: https://github.com/llvm/llvm-project/commit/4c810ecb68ef8e9090abd1927ec7262b35005ee7.diff
LOG: [libc] Add arm-32 syscall implementation.
The implementation currently supports only non-thumb mode. As a test for
the implementation, mmap and munmap functions have been enabled.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D132825
Added:
libc/src/__support/OSUtil/linux/arm/CMakeLists.txt
libc/src/__support/OSUtil/linux/arm/syscall.h
Modified:
libc/config/linux/arm/entrypoints.txt
libc/src/__support/OSUtil/linux/syscall.h
Removed:
################################################################################
diff --git a/libc/config/linux/arm/entrypoints.txt b/libc/config/linux/arm/entrypoints.txt
index 098300b8b0dc3..c88cbb1c3b5ef 100644
--- a/libc/config/linux/arm/entrypoints.txt
+++ b/libc/config/linux/arm/entrypoints.txt
@@ -48,6 +48,7 @@ set(TARGET_LIBC_ENTRYPOINTS
libc.src.string.strstr
libc.src.string.strtok
libc.src.string.strtok_r
+
# inttypes.h entrypoints
libc.src.inttypes.imaxabs
libc.src.inttypes.imaxdiv
@@ -74,6 +75,10 @@ set(TARGET_LIBC_ENTRYPOINTS
libc.src.stdlib.strtoll
libc.src.stdlib.strtoul
libc.src.stdlib.strtoull
+
+ # sys/mman.h entrypoints
+ libc.src.sys.mman.mmap
+ libc.src.sys.mman.munmap
)
set(TARGET_LIBM_ENTRYPOINTS
diff --git a/libc/src/__support/OSUtil/linux/arm/CMakeLists.txt b/libc/src/__support/OSUtil/linux/arm/CMakeLists.txt
new file mode 100644
index 0000000000000..733366f6d4a2e
--- /dev/null
+++ b/libc/src/__support/OSUtil/linux/arm/CMakeLists.txt
@@ -0,0 +1,7 @@
+add_header_library(
+ linux_arm_util
+ HDRS
+ syscall.h
+ DEPENDS
+ libc.src.__support.common
+)
diff --git a/libc/src/__support/OSUtil/linux/arm/syscall.h b/libc/src/__support/OSUtil/linux/arm/syscall.h
new file mode 100644
index 0000000000000..79cfff8859eee
--- /dev/null
+++ b/libc/src/__support/OSUtil/linux/arm/syscall.h
@@ -0,0 +1,120 @@
+//===--------- inline implementation of arm 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_ARM_SYSCALL_H
+#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
+
+#include "src/__support/common.h"
+
+#ifdef __thumb__
+#error "The arm syscall implementation does not yet support thumb flavor."
+#endif // __thumb__
+
+#define REGISTER_DECL_0 \
+ register long r7 __asm__("r7") = number; \
+ register long r0 __asm__("r0");
+#define REGISTER_DECL_1 \
+ register long r7 __asm__("r7") = number; \
+ register long r0 __asm__("r0") = arg1;
+#define REGISTER_DECL_2 \
+ REGISTER_DECL_1 \
+ register long r1 __asm__("r1") = arg2;
+#define REGISTER_DECL_3 \
+ REGISTER_DECL_2 \
+ register long r2 __asm__("r2") = arg3;
+#define REGISTER_DECL_4 \
+ REGISTER_DECL_3 \
+ register long r3 __asm__("r3") = arg4;
+#define REGISTER_DECL_5 \
+ REGISTER_DECL_4 \
+ register long r4 __asm__("r4") = arg5;
+#define REGISTER_DECL_6 \
+ REGISTER_DECL_5 \
+ register long r5 __asm__("r5") = arg6;
+
+#define REGISTER_CONSTRAINT_0 "r"(r7)
+#define REGISTER_CONSTRAINT_1 REGISTER_CONSTRAINT_0, "r"(r0)
+#define REGISTER_CONSTRAINT_2 REGISTER_CONSTRAINT_1, "r"(r1)
+#define REGISTER_CONSTRAINT_3 REGISTER_CONSTRAINT_2, "r"(r2)
+#define REGISTER_CONSTRAINT_4 REGISTER_CONSTRAINT_3, "r"(r3)
+#define REGISTER_CONSTRAINT_5 REGISTER_CONSTRAINT_4, "r"(r4)
+#define REGISTER_CONSTRAINT_6 REGISTER_CONSTRAINT_5, "r"(r5)
+
+#define SYSCALL_INSTR(input_constraint) \
+ LIBC_INLINE_ASM("svc 0" : "=r"(r0) : input_constraint : "memory", "cc")
+
+namespace __llvm_libc {
+
+__attribute__((always_inline)) inline long syscall(long number) {
+ REGISTER_DECL_0;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_0);
+ return r0;
+}
+
+__attribute__((always_inline)) inline long syscall(long number, long arg1) {
+ REGISTER_DECL_1;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_1);
+ return r0;
+}
+
+__attribute__((always_inline)) inline long syscall(long number, long arg1,
+ long arg2) {
+ REGISTER_DECL_2;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_2);
+ return r0;
+}
+
+__attribute__((always_inline)) inline long syscall(long number, long arg1,
+ long arg2, long arg3) {
+ REGISTER_DECL_3;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_3);
+ return r0;
+}
+
+__attribute__((always_inline)) inline long
+syscall(long number, long arg1, long arg2, long arg3, long arg4) {
+ REGISTER_DECL_4;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_4);
+ return r0;
+}
+
+__attribute__((always_inline)) inline long
+syscall(long number, long arg1, long arg2, long arg3, long arg4, long arg5) {
+ REGISTER_DECL_5;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_5);
+ return r0;
+}
+
+__attribute__((always_inline)) inline long syscall(long number, long arg1,
+ long arg2, long arg3,
+ long arg4, long arg5,
+ long arg6) {
+ REGISTER_DECL_6;
+ SYSCALL_INSTR(REGISTER_CONSTRAINT_6);
+ return r0;
+}
+
+} // namespace __llvm_libc
+
+#undef REGISTER_DECL_0
+#undef REGISTER_DECL_1
+#undef REGISTER_DECL_2
+#undef REGISTER_DECL_3
+#undef REGISTER_DECL_4
+#undef REGISTER_DECL_5
+#undef REGISTER_DECL_6
+
+#undef REGISTER_CONSTRAINT_0
+#undef REGISTER_CONSTRAINT_1
+#undef REGISTER_CONSTRAINT_2
+#undef REGISTER_CONSTRAINT_3
+#undef REGISTER_CONSTRAINT_4
+#undef REGISTER_CONSTRAINT_5
+#undef REGISTER_CONSTRAINT_6
+
+#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/linux/syscall.h b/libc/src/__support/OSUtil/linux/syscall.h
index 5887a62902b96..1756ee65e16d3 100644
--- a/libc/src/__support/OSUtil/linux/syscall.h
+++ b/libc/src/__support/OSUtil/linux/syscall.h
@@ -15,6 +15,8 @@
#include "x86_64/syscall.h"
#elif defined(LLVM_LIBC_ARCH_AARCH64)
#include "aarch64/syscall.h"
+#elif defined(LLVM_LIBC_ARCH_ARM)
+#include "arm/syscall.h"
#endif
namespace __llvm_libc {
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