Add __clear_cache implementation in libtcc1

Add __clear_cache function for flushing caches to libtcc1.

2 files changed, 34 insertions, 1 deletions

diff --git a/lib/Makefile b/lib/Makefile
index 300fa46..dfd01c3 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -24,6 +24,10 @@ ifndef TARGET
   ifneq ($(TARGETOS),Darwin)
    XCC = $(CC)
   endif
+ else
+ ifeq ($(ARCH),arm)
+  TARGET = arm
+ endif
  endif
  endif
  endif
@@ -41,6 +45,7 @@ cross : TCC = $(TOP)/$(TARGET)-tcc$(EXESUF)
 
 I386_O = libtcc1.o alloca86.o alloca86-bt.o $(BCHECK_O)
 X86_64_O = libtcc1.o alloca86_64.o
+ARM_O = libtcc1.o
 WIN32_O = $(I386_O) crt1.o wincrt1.o dllcrt1.o dllmain.o chkstk.o
 WIN64_O = $(X86_64_O) crt1.o wincrt1.o dllcrt1.o dllmain.o chkstk.o
 
@@ -66,11 +71,17 @@ ifeq "$(TARGET)" "x86_64"
  TGT = -DTCC_TARGET_X86_64
  XCC ?= $(TCC) -B$(TOP)
 else
+ifeq "$(TARGET)" "arm"
+ OBJ = $(addprefix $(DIR)/,$(ARM_O))
+ TGT = -DTCC_TARGET_ARM
+ XCC ?= $(TCC) -B$(TOP)
+else
  $(error libtcc1.a not supported on target '$(TARGET)')
 endif
 endif
 endif
 endif
+endif
 
 XFLAGS = $(CPPFLAGS) $(CFLAGS) $(TGT)
 
diff --git a/lib/libtcc1.c b/lib/libtcc1.c
index a717701..3103691 100644
--- a/lib/libtcc1.c
+++ b/lib/libtcc1.c
@@ -107,7 +107,7 @@ union float_long {
 };
 
 /* XXX: we don't support several builtin supports for now */
-#ifndef __x86_64__
+#if !defined(__x86_64__) && !defined(__arm__)
 
 /* XXX: use gcc/tcc intrinsic ? */
 #if defined(__i386__)
@@ -713,6 +713,28 @@ void __clear_cache(char *beginning, char *end)
 {
 }
 
+#elif defined(__arm__)
+
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <sys/syscall.h>
+
+void __clear_cache(char *beginning, char *end)
+{
+/* __ARM_NR_cacheflush is kernel private and should not be used in user space.
+ * However, there is no ARM asm parser in tcc so we use it for now */
+#if 1
+    syscall(__ARM_NR_cacheflush);
+#else
+    __asm__ ("push {r7}\n\t"
+             "mov r7, #0xf0002\n\t"
+             "mov r2, #0\n\t"
+             "swi 0\n\t"
+             "pop {r7}\n\t"
+             "ret");
+#endif
+}
+
 #else
 #warning __clear_cache not defined for this architecture, avoid using tcc -run
 #endif