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Re: ARM: Clear icache when creating a closure
On 07/25/2011 10:33 AM, Andrew Haley wrote:
> On 21/07/11 16:33, Joseph S. Myers wrote:
>> My suggestion would be putting the instruction sequence in a .s file,
>> rather than hardcoding the instruction encodings here, and writing the
>> code to read from the sequence as assembled by the assembler. That way it
>> will have the appropriate mapping symbols to mark it as ARM-mode code and
>> the linker will deal with adjusting endianness, so you don't need to test
>> for BE-8 at all.
I did this, and it passes the testsuite. Is it OK?
Andrew.
2011-07-26 Andrew Haley <aph@redhat.com>
* src/arm/ffi.c (FFI_INIT_TRAMPOLINE): Remove hard-coded assembly
instructions.
* src/arm/sysv.S (ffi_arm_trampoline): Put them here instead.
Index: src/arm/ffi.c
===================================================================
--- src/arm/ffi.c (revision 176744)
+++ src/arm/ffi.c (working copy)
@@ -337,14 +337,14 @@
/* How to make a trampoline. */
+extern unsigned int ffi_arm_trampoline[3];
+
#define FFI_INIT_TRAMPOLINE(TRAMP,FUN,CTX) \
({ unsigned char *__tramp = (unsigned char*)(TRAMP); \
unsigned int __fun = (unsigned int)(FUN); \
unsigned int __ctx = (unsigned int)(CTX); \
unsigned char *insns = (unsigned char *)(CTX); \
- *(unsigned int*) &__tramp[0] = 0xe92d000f; /* stmfd sp!, {r0-r3} */ \
- *(unsigned int*) &__tramp[4] = 0xe59f0000; /* ldr r0, [pc] */ \
- *(unsigned int*) &__tramp[8] = 0xe59ff000; /* ldr pc, [pc] */ \
+ memcpy (__tramp, ffi_arm_trampoline, sizeof ffi_arm_trampoline); \
*(unsigned int*) &__tramp[12] = __ctx; \
*(unsigned int*) &__tramp[16] = __fun; \
__clear_cache((&__tramp[0]), (&__tramp[19])); /* Clear data mapping. */ \
Index: src/arm/sysv.S
===================================================================
--- src/arm/sysv.S (revision 176744)
+++ src/arm/sysv.S (working copy)
@@ -461,6 +461,11 @@
UNWIND .fnend
.size CNAME(ffi_closure_VFP),.ffi_closure_VFP_end-CNAME(ffi_closure_VFP)
+ENTRY(ffi_arm_trampoline)
+ stmfd sp!, {r0-r3}
+ ldr r0, [pc]
+ ldr pc, [pc]
+
#if defined __ELF__ && defined __linux__
.section .note.GNU-stack,"",%progbits
#endif