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author | Oren Ben Simhon <oren.ben.simhon@intel.com> | 2018-03-17 13:29:46 +0000 |
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committer | Oren Ben Simhon <oren.ben.simhon@intel.com> | 2018-03-17 13:29:46 +0000 |
commit | fdd72fd5225dedb4431473fb3ac7b3d45fc8ed00 (patch) | |
tree | b1819bd5c756e40209091ea07d752efab4cf83ac /llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp | |
parent | dbcf1bf503880084e33e57e9fb916a66703d18d7 (diff) | |
download | bcm5719-llvm-fdd72fd5225dedb4431473fb3ac7b3d45fc8ed00.tar.gz bcm5719-llvm-fdd72fd5225dedb4431473fb3ac7b3d45fc8ed00.zip |
[X86] Added support for nocf_check attribute for indirect Branch Tracking
X86 Supports Indirect Branch Tracking (IBT) as part of Control-Flow Enforcement Technology (CET).
IBT instruments ENDBR instructions used to specify valid targets of indirect call / jmp.
TheĀ `nocf_check` attribute has two roles in the context of X86 IBT technology:
1. Appertains to a function - do not add ENDBR instruction at the beginning of the function.
2. Appertains to a function pointer - do not track the target function of this pointer by adding nocf_check prefix to the indirect-call instruction.
This patch implementsĀ `nocf_check` context for Indirect Branch Tracking.
It also auto generatesĀ `nocf_check` prefixes before indirect branchs to jump tables that are guarded by range checks.
Differential Revision: https://reviews.llvm.org/D41879
llvm-svn: 327767
Diffstat (limited to 'llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp')
-rw-r--r-- | llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp b/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp index 5860285378e..5941e06d76c 100644 --- a/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp +++ b/llvm/lib/Target/X86/InstPrinter/X86ATTInstPrinter.cpp @@ -54,6 +54,9 @@ void X86ATTInstPrinter::printInst(const MCInst *MI, raw_ostream &OS, if ((TSFlags & X86II::LOCK) || (Flags & X86::IP_HAS_LOCK)) OS << "\tlock\t"; + if ((TSFlags & X86II::NOTRACK) || (Flags & X86::IP_HAS_NOTRACK)) + OS << "\tnotrack\t"; + if (Flags & X86::IP_HAS_REPEAT_NE) OS << "\trepne\t"; else if (Flags & X86::IP_HAS_REPEAT) |