2012-03-21 Harshit Chopra <hars...@google.com> Minor changes: i386.c: made check_should_patch_current_function C90 compatible. i386.md: Added '\t' to bytes generated by ix86_output_function_nops_prologue_epilogue for proper formatting of assembly. patch-functions-*.c: Fixed verification in tests. Added a test to verify nop-bytes generated for sibling calls and another test to verify a binary with nop-bytes runs properly.
* gcc/config/i386/i386.c (check_should_patch_current_function): * gcc/config/i386/i386.md: * gcc/testsuite/gcc.target/i386/patch-functions-1.c (void foo): (int main): * gcc/testsuite/gcc.target/i386/patch-functions-2.c: * gcc/testsuite/gcc.target/i386/patch-functions-3.c: * gcc/testsuite/gcc.target/i386/patch-functions-4.c: * gcc/testsuite/gcc.target/i386/patch-functions-5.c: * gcc/testsuite/gcc.target/i386/patch-functions-6.c: * gcc/testsuite/gcc.target/i386/patch-functions-7.c: * gcc/testsuite/gcc.target/i386/patch-functions-8.c (int foo): (int bar): * gcc/testsuite/gcc.target/i386/patch-functions-sibling-call.c: Testing method: make check-gcc RUNTESTFLAGS="i386.exp=patch-functions* --target_board=\"unix{-m32,}\"" Patch to be applied to google/main. diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 08bd5f0..be1f7a4 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -10981,6 +10981,7 @@ check_should_patch_current_function (void) const char* func_name = NULL; struct loops loops; int num_loops = 0; + int min_functions_instructions; /* Patch the function if it has at least a loop. */ if (!patch_functions_ignore_loops) @@ -11007,7 +11008,7 @@ check_should_patch_current_function (void) strcmp("main", func_name) == 0) return true; - int min_functions_instructions = + min_functions_instructions = PARAM_VALUE (PARAM_FUNCTION_PATCH_MIN_INSTRUCTIONS); if (min_functions_instructions > 0) { diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index 08353ff..38a04ae 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -11688,7 +11688,7 @@ /* Emit 10 nop bytes after ret. */ if (ix86_output_function_nops_prologue_epilogue (asm_out_file, FUNCTION_PATCH_EPILOGUE_SECTION, - "ret", + "\tret", 10)) return ""; } @@ -11712,7 +11712,7 @@ /* Emit 9 nop bytes after rep;ret. */ if (ix86_output_function_nops_prologue_epilogue (asm_out_file, FUNCTION_PATCH_EPILOGUE_SECTION, - "rep\;ret", + "\trep\;ret", 9)) return ""; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-1.c b/gcc/testsuite/gcc.target/i386/patch-functions-1.c index 308e8c3..aa1f424 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-1.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-1.c @@ -1,5 +1,5 @@ /* Verify -mpatch-functions-for-instrumentation works. */ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation" } */ @@ -8,13 +8,16 @@ /* Check nop-bytes at end. */ /* { dg-final { scan-assembler "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -void foo() { +__attribute__ ((noinline)) +void foo() +{ /* Dummy loop. */ int x = 0; while (++x); } -int main() { +int main() +{ foo(); return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-2.c b/gcc/testsuite/gcc.target/i386/patch-functions-2.c index 6baad32..78de867 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-2.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-2.c @@ -1,4 +1,4 @@ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation -mno-patch-functions-main-always" } */ @@ -8,11 +8,14 @@ /* { dg-final { scan-assembler-not ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ /* { dg-final { scan-assembler-not "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -void foo() { +__attribute__ ((noinline)) +void foo() +{ int x = 0; } -int main() { +int main() +{ foo(); return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-3.c b/gcc/testsuite/gcc.target/i386/patch-functions-3.c index 49b57a8..9e8eb52 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-3.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-3.c @@ -1,4 +1,4 @@ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation --param function-patch-min-instructions=0" } */ @@ -8,11 +8,14 @@ /* { dg-final { scan-assembler ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ /* { dg-final { scan-assembler "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -void foo() { +__attribute__ ((noinline)) +void foo() +{ int x = 0; } -int main() { +int main() +{ foo(); return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-4.c b/gcc/testsuite/gcc.target/i386/patch-functions-4.c index 5fcbd0f..7a031d7 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-4.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-4.c @@ -1,4 +1,4 @@ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation -mpatch-functions-ignore-loops -mno-patch-functions-main-always" } */ @@ -8,12 +8,15 @@ /* { dg-final { scan-assembler-not ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ /* { dg-final { scan-assembler-not "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -void foo() { +__attribute__ ((noinline)) +void foo() +{ int x = 0; while (++x); } -int main() { +int main() +{ foo(); return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-5.c b/gcc/testsuite/gcc.target/i386/patch-functions-5.c index 1f9cccf..cd6a014 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-5.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-5.c @@ -1,4 +1,4 @@ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation -mpatch-functions-ignore-loops --param function-patch-min-instructions=0" } */ @@ -8,12 +8,15 @@ /* { dg-final { scan-assembler ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ /* { dg-final { scan-assembler "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -void foo() { +__attribute__ ((noinline)) +void foo() +{ int x = 0; while (++x); } -int main() { +int main() +{ foo(); return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-6.c b/gcc/testsuite/gcc.target/i386/patch-functions-6.c index 5bf844f..c1d6446 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-6.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-6.c @@ -1,4 +1,4 @@ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation" } */ @@ -8,7 +8,8 @@ /* { dg-final { scan-assembler ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ /* { dg-final { scan-assembler "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -int main(int argc, char **argv) { +int main() +{ int x = 0; return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-7.c b/gcc/testsuite/gcc.target/i386/patch-functions-7.c index e2c50a0..f625298 100644 --- a/gcc/testsuite/gcc.target/i386/patch-functions-7.c +++ b/gcc/testsuite/gcc.target/i386/patch-functions-7.c @@ -1,4 +1,4 @@ -/* { dg-do run } */ +/* { dg-do compile } */ /* { dg-require-effective-target lp64 } */ /* { dg-options "-mpatch-functions-for-instrumentation -mno-patch-functions-main-always" } */ @@ -8,7 +8,8 @@ /* { dg-final { scan-assembler-not ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ /* { dg-final { scan-assembler-not "ret(.*).byte\t0x90(.*).byte\t0x90" } } */ -int main(int argc, char **argv) { +int main() +{ int x = 0; return 0; } diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-8.c b/gcc/testsuite/gcc.target/i386/patch-functions-8.c new file mode 100644 index 0000000..436379c --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/patch-functions-8.c @@ -0,0 +1,29 @@ +/* Verify -mpatch-functions-for-instrumentation works. */ +/* { dg-do run } */ +/* { dg-require-effective-target lp64 } */ + +/* -O2 forces a sibling call for foo from bar. */ +/* { dg-options "-O2 -mpatch-functions-for-instrumentation --param function-patch-min-instructions=0" } */ + +__attribute__ ((noinline)) +int foo() +{ + /* Dummy loop. */ + int x = 10; + int y = 100; + while (--x) + ++y; + return y; +} + +__attribute__ ((noinline)) +int bar() +{ + return foo(); +} + +int main() +{ + bar(); + return 0; +} diff --git a/gcc/testsuite/gcc.target/i386/patch-functions-sibling-call.c b/gcc/testsuite/gcc.target/i386/patch-functions-sibling-call.c new file mode 100644 index 0000000..847a95c --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/patch-functions-sibling-call.c @@ -0,0 +1,26 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target lp64 } */ +/* -O2 forces a sibling call. */ +/* { dg-options "-O2 -mpatch-functions-for-instrumentation" } */ + +/* { dg-final { scan-assembler ".byte\t0xeb,0x09(.*).byte\t0x90" } } */ + +/* Checks correct nop-bytes are generated just before a sibling call. */ +/* { dg-final { scan-assembler ".byte\t0xeb,0x09(.*).byte\t0x90(.*)jmp" } } */ + +/* Not instrumented as function has no loop and is small. */ +__attribute__ ((noinline)) +int foo(int n) +{ + int x = 0; + return n + 10; +} + +__attribute__ ((noinline)) +int bar(int n) +{ + /* Dummy loop. */ + while (--n) + n = n * 2; + return foo(n); +} -- This patch is available for review at http://codereview.appspot.com/5877043