[libc-commits] [libc] [libc] Add `scanf` support to the GPU build (PR #104812)
Joseph Huber via libc-commits
libc-commits at lists.llvm.org
Wed Aug 21 15:04:02 PDT 2024
https://github.com/jhuber6 updated https://github.com/llvm/llvm-project/pull/104812
>From ff7dcb8e8431d4a35ea21a91436e27a47832521c Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Mon, 19 Aug 2024 11:22:36 -0500
Subject: [PATCH 1/3] [libc] Add `scanf` support to the GPU build
Summary:
The `scanf` function has a "system file" configuration, which is pretty
much what the GPU implementation does at this point. So we should be
able to use it in much the same way.
---
libc/config/gpu/entrypoints.txt | 2 +
libc/docs/gpu/support.rst | 2 +
libc/src/stdio/CMakeLists.txt | 2 +-
libc/src/stdio/scanf_core/CMakeLists.txt | 46 ++++++++++++--------
libc/src/stdio/scanf_core/vfscanf_internal.h | 26 ++++++++++-
5 files changed, 59 insertions(+), 19 deletions(-)
diff --git a/libc/config/gpu/entrypoints.txt b/libc/config/gpu/entrypoints.txt
index bbae3298fae615..d7f35bc1edf5a0 100644
--- a/libc/config/gpu/entrypoints.txt
+++ b/libc/config/gpu/entrypoints.txt
@@ -192,6 +192,8 @@ set(TARGET_LIBC_ENTRYPOINTS
libc.src.stdio.vsprintf
libc.src.stdio.asprintf
libc.src.stdio.vasprintf
+ libc.src.stdio.scanf
+ libc.src.stdio.fscanf
libc.src.stdio.sscanf
libc.src.stdio.vsscanf
libc.src.stdio.feof
diff --git a/libc/docs/gpu/support.rst b/libc/docs/gpu/support.rst
index 5ef298a2ba58f2..c8b1052ce16895 100644
--- a/libc/docs/gpu/support.rst
+++ b/libc/docs/gpu/support.rst
@@ -239,6 +239,8 @@ snprintf |check|
vsprintf |check|
vsnprintf |check|
sscanf |check|
+scanf |check|
+fscanf |check|
putchar |check| |check|
fclose |check| |check|
fopen |check| |check|
diff --git a/libc/src/stdio/CMakeLists.txt b/libc/src/stdio/CMakeLists.txt
index bc5ef5fe0e9b48..372b8fc8192455 100644
--- a/libc/src/stdio/CMakeLists.txt
+++ b/libc/src/stdio/CMakeLists.txt
@@ -101,7 +101,7 @@ list(APPEND scanf_deps
libc.hdr.types.FILE
)
-if(LLVM_LIBC_FULL_BUILD)
+if(LLVM_LIBC_FULL_BUILD AND NOT LIBC_TARGET_OS_IS_GPU)
list(APPEND scanf_deps
libc.src.__support.File.file
libc.src.__support.File.platform_file
diff --git a/libc/src/stdio/scanf_core/CMakeLists.txt b/libc/src/stdio/scanf_core/CMakeLists.txt
index e2b49e0c915284..5c00ae0c9973c2 100644
--- a/libc/src/stdio/scanf_core/CMakeLists.txt
+++ b/libc/src/stdio/scanf_core/CMakeLists.txt
@@ -92,21 +92,33 @@ add_object_library(
libc.src.__support.str_to_float
)
-if(NOT (TARGET libc.src.__support.File.file) AND LLVM_LIBC_FULL_BUILD)
- # Not all platforms have a file implementation. If file is unvailable, and a
- # full build is requested, then we must skip all file based printf sections.
- return()
+if(LIBC_TARGET_OS_IS_GPU)
+ add_header_library(
+ vfscanf_internal
+ HDRS
+ vfscanf_internal.h
+ DEPENDS
+ .reader
+ .scanf_main
+ libc.include.stdio
+ libc.src.__support.arg_list
+ libc.src.stdio.getc
+ libc.src.stdio.ungetc
+ libc.src.stdio.ferror
+ COMPILE_OPTIONS
+ -DLIBC_COPT_STDIO_USE_SYSTEM_FILE
+ )
+elseif(TARGET libc.src.__support.File.file OR (NOT LLVM_LIBC_FULL_BUILD))
+ add_header_library(
+ vfscanf_internal
+ HDRS
+ vfscanf_internal.h
+ DEPENDS
+ .reader
+ .scanf_main
+ libc.include.stdio
+ libc.src.__support.File.file
+ libc.src.__support.arg_list
+ ${use_system_file}
+ )
endif()
-
-add_header_library(
- vfscanf_internal
- HDRS
- vfscanf_internal.h
- DEPENDS
- .reader
- .scanf_main
- libc.include.stdio
- libc.src.__support.File.file
- libc.src.__support.arg_list
- ${use_system_file}
-)
diff --git a/libc/src/stdio/scanf_core/vfscanf_internal.h b/libc/src/stdio/scanf_core/vfscanf_internal.h
index 2b0072a6ae35f3..68848375eee229 100644
--- a/libc/src/stdio/scanf_core/vfscanf_internal.h
+++ b/libc/src/stdio/scanf_core/vfscanf_internal.h
@@ -12,9 +12,16 @@
#include "src/__support/File/file.h"
#include "src/__support/arg_list.h"
#include "src/__support/macros/config.h"
+#include "src/__support/macros/properties/architectures.h"
#include "src/stdio/scanf_core/reader.h"
#include "src/stdio/scanf_core/scanf_main.h"
+#if defined(LIBC_TARGET_ARCH_IS_GPU)
+#include "src/stdio/ferror.h"
+#include "src/stdio/getc.h"
+#include "src/stdio/ungetc.h"
+#endif
+
#include "hdr/types/FILE.h"
#include <stddef.h>
@@ -22,7 +29,24 @@ namespace LIBC_NAMESPACE_DECL {
namespace internal {
-#ifndef LIBC_COPT_STDIO_USE_SYSTEM_FILE
+#if defined(LIBC_TARGET_ARCH_IS_GPU)
+// Since ungetc_unlocked isn't always available, we don't acquire the lock for
+// system files.
+LIBC_INLINE void flockfile(::FILE *) { return; }
+
+LIBC_INLINE void funlockfile(::FILE *) { return; }
+
+LIBC_INLINE int getc(void *f) {
+ return LIBC_NAMESPACE::getc(reinterpret_cast<::FILE *>(f));
+}
+
+LIBC_INLINE void ungetc(int c, void *f) {
+ LIBC_NAMESPACE::ungetc(c, reinterpret_cast<::FILE *>(f));
+}
+
+LIBC_INLINE int ferror_unlocked(::FILE *f) { return LIBC_NAMESPACE::ferror(f); }
+
+#elif !defined(LIBC_COPT_STDIO_USE_SYSTEM_FILE)
LIBC_INLINE void flockfile(FILE *f) {
reinterpret_cast<LIBC_NAMESPACE::File *>(f)->lock();
>From d1bc5fc4a11b51d29a7f0594dfeadacc56ff6f45 Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Tue, 20 Aug 2024 13:35:05 -0500
Subject: [PATCH 2/3] Update vfscanf_internal.h
---
libc/src/stdio/scanf_core/vfscanf_internal.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/libc/src/stdio/scanf_core/vfscanf_internal.h b/libc/src/stdio/scanf_core/vfscanf_internal.h
index 68848375eee229..46a22e3731f165 100644
--- a/libc/src/stdio/scanf_core/vfscanf_internal.h
+++ b/libc/src/stdio/scanf_core/vfscanf_internal.h
@@ -30,8 +30,10 @@ namespace LIBC_NAMESPACE_DECL {
namespace internal {
#if defined(LIBC_TARGET_ARCH_IS_GPU)
-// Since ungetc_unlocked isn't always available, we don't acquire the lock for
-// system files.
+// The GPU build provides FILE access through the host operating system's
+// library. So here we simply use the public entrypoints like in the SYSTEM_FILE
+// interface.
+// FIXME: We do not acquire any locks here, so this is not thread safe.
LIBC_INLINE void flockfile(::FILE *) { return; }
LIBC_INLINE void funlockfile(::FILE *) { return; }
>From ee2831d2702bd945a738a420462dc4bfa400a5c2 Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Wed, 21 Aug 2024 17:03:52 -0500
Subject: [PATCH 3/3] Update vfscanf_internal.h
---
libc/src/stdio/scanf_core/vfscanf_internal.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libc/src/stdio/scanf_core/vfscanf_internal.h b/libc/src/stdio/scanf_core/vfscanf_internal.h
index 46a22e3731f165..67126431fcded5 100644
--- a/libc/src/stdio/scanf_core/vfscanf_internal.h
+++ b/libc/src/stdio/scanf_core/vfscanf_internal.h
@@ -32,7 +32,7 @@ namespace internal {
#if defined(LIBC_TARGET_ARCH_IS_GPU)
// The GPU build provides FILE access through the host operating system's
// library. So here we simply use the public entrypoints like in the SYSTEM_FILE
-// interface.
+// interface. Entrypoints should normally not call others, this is an exception.
// FIXME: We do not acquire any locks here, so this is not thread safe.
LIBC_INLINE void flockfile(::FILE *) { return; }
More information about the libc-commits
mailing list