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| author | Andi Kleen <ak@linux.intel.com> | 2010-08-07 21:24:05 -0700 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2010-08-07 21:24:05 -0700 |
| commit | d22e4cc9397ed41534c9422d0b0ffef8c77bfa53 (patch) | |
| tree | cf2a4b5b9970dcb959f2b41e44e38ff2914657bd /sysdeps | |
| parent | 805bc17d6883bf6d47e49620d6f8e1b97cac9901 (diff) | |
| download | glibc-d22e4cc9397ed41534c9422d0b0ffef8c77bfa53.tar.gz glibc-d22e4cc9397ed41534c9422d0b0ffef8c77bfa53.tar.xz glibc-d22e4cc9397ed41534c9422d0b0ffef8c77bfa53.zip | |
x86: Add support for frame pointer less mcount
Diffstat (limited to 'sysdeps')
| -rw-r--r-- | sysdeps/i386/i386-mcount.S | 25 | ||||
| -rw-r--r-- | sysdeps/x86_64/_mcount.S | 38 |
2 files changed, 63 insertions, 0 deletions
diff --git a/sysdeps/i386/i386-mcount.S b/sysdeps/i386/i386-mcount.S index 8b11adb2e3..43bc0194dd 100644 --- a/sysdeps/i386/i386-mcount.S +++ b/sysdeps/i386/i386-mcount.S @@ -53,3 +53,28 @@ C_LABEL(_mcount) #undef mcount weak_alias (_mcount, mcount) + + /* Same as above, but doesn't require a frame pointer */ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(__fentry__) + ASM_TYPE_DIRECTIVE(C_SYMBOL_NAME(__fentry__), @function) + .align ALIGNARG(4) +C_LABEL(__fentry__) + /* Save the caller-clobbered registers. */ + pushl %eax + pushl %ecx + pushl %edx + + movl 12(%esp), %edx + movl 16(%esp), %eax + + /* No need to access the PLT or GOT, __mcount_internal is an + internal function and we can make a relative call. */ + call C_SYMBOL_NAME(__mcount_internal) + + /* Pop the saved registers. Please note that `__fentry__' has no + return value. */ + popl %edx + popl %ecx + popl %eax + ret + ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(__fentry__)) diff --git a/sysdeps/x86_64/_mcount.S b/sysdeps/x86_64/_mcount.S index c005932c0c..ef046dc3c5 100644 --- a/sysdeps/x86_64/_mcount.S +++ b/sysdeps/x86_64/_mcount.S @@ -65,3 +65,41 @@ C_LABEL(_mcount) #undef mcount weak_alias (_mcount, mcount) + + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(__fentry__) + ASM_TYPE_DIRECTIVE(C_SYMBOL_NAME(__fentry__), @function) + .align ALIGNARG(4) +C_LABEL(__fentry__) + /* Allocate space for 7 registers. */ + subq $64,%rsp + movq %rax,(%rsp) + movq %rcx,8(%rsp) + movq %rdx,16(%rsp) + movq %rsi,24(%rsp) + movq %rdi,32(%rsp) + movq %r8,40(%rsp) + movq %r9,48(%rsp) + + /* Setup parameter for __mcount_internal. */ + /* selfpc is the return address on the stack. */ + movq 64(%rsp),%rsi + /* caller is the return address above it */ + movq 72(%rsp),%rdi +#ifdef PIC + call C_SYMBOL_NAME(__mcount_internal)@PLT +#else + call C_SYMBOL_NAME(__mcount_internal) +#endif + /* Pop the saved registers. Please note that `__fentry__' has no + return value. */ + movq 48(%rsp),%r9 + movq 40(%rsp),%r8 + movq 32(%rsp),%rdi + movq 24(%rsp),%rsi + movq 16(%rsp),%rdx + movq 8(%rsp),%rcx + movq (%rsp),%rax + addq $64,%rsp + ret + + ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(__fentry__)) |