[X86] WaitPKG instructions
Three new instructions:
umonitor - Sets up a linear address range to be
monitored by hardware and activates the monitor.
The address range should be a writeback memory
caching type.
umwait - A hint that allows the processor to
stop instruction execution and enter an
implementation-dependent optimized state
until occurrence of a class of events.
tpause - Directs the processor to enter an
implementation-dependent optimized state
until the TSC reaches the value in EDX:EAX.
Also modifying the description of the mfence
instruction, as the rep prefix (0xF3) was allowed
before, which would conflict with umonitor during
disassembly.
Before:
$ echo 0xf3,0x0f,0xae,0xf0 | llvm-mc -disassemble
.text
mfence
After:
$ echo 0xf3,0x0f,0xae,0xf0 | llvm-mc -disassemble
.text
umonitor %rax
Reviewers: craig.topper, zvi
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D45253
llvm-svn: 330462
diff --git a/llvm/lib/Support/Host.cpp b/llvm/lib/Support/Host.cpp
index 3337d8a..5a55e55 100644
--- a/llvm/lib/Support/Host.cpp
+++ b/llvm/lib/Support/Host.cpp
@@ -1250,6 +1250,7 @@
Features["prefetchwt1"] = HasLeaf7 && ((ECX >> 0) & 1);
Features["avx512vbmi"] = HasLeaf7 && ((ECX >> 1) & 1) && HasAVX512Save;
Features["pku"] = HasLeaf7 && ((ECX >> 4) & 1);
+ Features["waitpkg"] = HasLeaf7 && ((ECX >> 5) & 1);
Features["avx512vbmi2"] = HasLeaf7 && ((ECX >> 6) & 1) && HasAVX512Save;
Features["shstk"] = HasLeaf7 && ((ECX >> 7) & 1);
Features["gfni"] = HasLeaf7 && ((ECX >> 8) & 1);