From: Andreas Krebbel Date: Thu, 14 May 2020 06:16:27 +0000 (+0200) Subject: IBM Z: stack clash prot: add missing updates of last_probe_offset X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=868d351e232371eec4b40e83014a617d0d46f985;p=gcc.git IBM Z: stack clash prot: add missing updates of last_probe_offset After emitting probes in a loop last_probe_offset needs to be updated. Not doing this usually assumes a too low distance to the last access when emitting the remainder leading to stack probes being omitted. gcc/ChangeLog: 2020-05-14 Andreas Krebbel * config/s390/s390.c (allocate_stack_space): Add missing updates of last_probe_offset. gcc/testsuite/ChangeLog: 2020-05-14 Andreas Krebbel * gcc.target/s390/stack-clash-1.c: New test. --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 0b326ee09e8..51d3e425ad5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2020-05-14 Andreas Krebbel + + * config/s390/s390.c (allocate_stack_space): Add missing updates + of last_probe_offset. + 2020-05-14 Andreas Krebbel * config/s390/s390.md ("allocate_stack"): Call diff --git a/gcc/config/s390/s390.c b/gcc/config/s390/s390.c index 18332271ed7..b4897256af5 100644 --- a/gcc/config/s390/s390.c +++ b/gcc/config/s390/s390.c @@ -10996,6 +10996,8 @@ allocate_stack_space (rtx size, HOST_WIDE_INT last_probe_offset, stack_pointer_rtx, offset)); } + if (num_probes > 0) + last_probe_offset = INTVAL (offset); dump_stack_clash_frame_info (PROBE_INLINE, residual != 0); } else @@ -11029,6 +11031,7 @@ allocate_stack_space (rtx size, HOST_WIDE_INT last_probe_offset, s390_prologue_plus_offset (stack_pointer_rtx, temp_reg, const0_rtx, true); temp_reg_clobbered_p = true; + last_probe_offset = INTVAL (offset); dump_stack_clash_frame_info (PROBE_LOOP, residual != 0); } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index bb3e4c86adc..8ff0bbcc85b 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2020-05-14 Andreas Krebbel + + * gcc.target/s390/stack-clash-1.c: New test. + 2020-05-14 Andreas Krebbel * gcc.target/s390/stack-clash-3.c: New test. diff --git a/gcc/testsuite/gcc.target/s390/stack-clash-1.c b/gcc/testsuite/gcc.target/s390/stack-clash-1.c new file mode 100644 index 00000000000..3d29cab9446 --- /dev/null +++ b/gcc/testsuite/gcc.target/s390/stack-clash-1.c @@ -0,0 +1,17 @@ +/* Make sure a stack probe is emitted also for the remaining bytes + after the loop probing the large chunk. */ + +/* { dg-do compile } */ +/* { dg-options "-O2 -march=z9-ec -fstack-clash-protection" } */ + +void large_stack() { + volatile int stack[8000]; + int i; + for (i = 0; i < sizeof(stack) / sizeof(int); ++i) + stack[i] = i; +} + +/* We use a compare for the stack probe. There needs to be one inside + a loop and another for the remaining bytes. */ +/* { dg-final { scan-assembler-times "cg\t" 2 { target lp64 } } } */ +/* { dg-final { scan-assembler-times "c\t" 2 { target { ! lp64 } } } } */