2021-05-13 Bill Schmidt <[email protected]>
gcc/
* config/rs6000/rs6000.c (rs6000_option_override_internal):
Disable shrink wrap when inserting ROP-protect instructions.
* config/rs6000/rs6000.opt (mrop-protect): New option.
(mprivileged): Likewise.
* doc/invoke.texi: Document mrop-protect and mprivileged.
---
gcc/config/rs6000/rs6000.c | 4 ++++
gcc/config/rs6000/rs6000.opt | 8 ++++++++
gcc/doc/invoke.texi | 20 ++++++++++++++++++--
3 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index d1b76f6ec41..53a9f5411c7 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -4040,6 +4040,10 @@ rs6000_option_override_internal (bool global_init_p)
&& ((rs6000_isa_flags_explicit & OPTION_MASK_QUAD_MEMORY_ATOMIC) == 0))
rs6000_isa_flags |= OPTION_MASK_QUAD_MEMORY_ATOMIC;
+ /* If we are inserting ROP-protect instructions, disable shrink wrap. */
+ if (rs6000_rop_protect)
+ flag_shrink_wrap = 0;
+
/* If we can shrink-wrap the TOC register save separately, then use
-msave-toc-indirect unless explicitly disabled. */
if ((rs6000_isa_flags_explicit & OPTION_MASK_SAVE_TOC_INDIRECT) == 0
diff --git a/gcc/config/rs6000/rs6000.opt b/gcc/config/rs6000/rs6000.opt
index 0dbdf753673..f66ef20a102 100644
--- a/gcc/config/rs6000/rs6000.opt
+++ b/gcc/config/rs6000/rs6000.opt
@@ -619,3 +619,11 @@ Generate (do not generate) MMA instructions.
mrelative-jumptables
Target Undocumented Var(rs6000_relative_jumptables) Init(1) Save
+
+mrop-protect
+Target Var(rs6000_rop_protect) Init(0)
+Enable instructions that guard against return-oriented programming attacks.
+
+mprivileged
+Target Var(rs6000_privileged) Init(0)
+Enable generation of instructions that require privileged state.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 519881509a6..92549524583 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -1240,7 +1240,8 @@ See RS/6000 and PowerPC Options.
-mgnu-attribute -mno-gnu-attribute @gol
-mstack-protector-guard=@var{guard} -mstack-protector-guard-reg=@var{reg} @gol
-mstack-protector-guard-offset=@var{offset} -mprefixed -mno-prefixed @gol
--mpcrel -mno-pcrel -mmma -mno-mmma}
+-mpcrel -mno-pcrel -mmma -mno-mmma -mrop-protect -mno-rop-protect @gol
+-mprivileged -mno-privileged}
@emph{RX Options}
@gccoptlist{-m64bit-doubles -m32bit-doubles -fpu -nofpu@gol
@@ -27029,7 +27030,8 @@ following options:
-mmulhw -mdlmzb -mmfpgpr -mvsx @gol
-mcrypto -mhtm -mpower8-fusion -mpower8-vector @gol
-mquad-memory -mquad-memory-atomic -mfloat128 @gol
--mfloat128-hardware -mprefixed -mpcrel -mmma}
+-mfloat128-hardware -mprefixed -mpcrel -mmma @gol
+-mrop-protect}
The particular options set for any particular CPU varies between
compiler versions, depending on what setting seems to produce optimal
@@ -28034,6 +28036,20 @@ store instructions when the option
@option{-mcpu=future} is used.
Generate (do not generate) the MMA instructions when the option
@option{-mcpu=future} is used.
+@item -mrop-protect
+@itemx -mno-rop-protect
+@opindex mrop-protect
+@opindex mno-rop-protect
+Generate (do not generate) ROP protection instructions when the target
+processor supports them. Currently this option disables the shrink-wrap
+optimization (@option{-fshrink-wrap}).
+
+@item -mprivileged
+@itemx -mno-privileged
+@opindex mprivileged
+@opindex mno-privileged
+Generate (do not generate) instructions for privileged state.
+
@item -mblock-ops-unaligned-vsx
@itemx -mno-block-ops-unaligned-vsx
@opindex block-ops-unaligned-vsx
--
2.27.0