Shadow stack solution introduces a new stack for return addresses only.
The stack has a Shadow Stack Pointer (SSP) that points to the last address to which we expect to return.
If we return to a different address an exception is triggered.
This patch includes shadow stack intrinsics as well as the corresponding CET header.
It includes CET clang flags for shadow stack and Indirect Branch Tracking.
For more information, please see the following:
https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf
Differential Revision: https://reviews.llvm.org/D40224
Change-Id: I79ad0925a028bbc94c8ecad75f6daa2f214171f1
llvm-svn: 318995
1. Adds the command line flag for clzero.
2. Includes the clzero flag under znver1.
3. Defines the macro for clzero.
4. Adds a new file which has the intrinsic definition for clzero instruction.
Patch by Ganesh Gopalasubramanian with some additional tests from me.
Differential revision: https://reviews.llvm.org/D29386
llvm-svn: 294559
Add -m[no-]x87 and -m[no-]80387 options to control FeatureX87.
-m[no-]80387 options is added for compatibility with GCC.
Differential Revision: http://reviews.llvm.org/D19658
llvm-svn: 268489