Add Hardware Transactional Memory (HTM) Support
This patch adds Hardware Transaction Memory (HTM) support supported by ISA 2.07
(POWER8). The intrinsic support is based on GCC one [1], but currently only the
'PowerPC HTM Low Level Built-in Function' are implemented.
The HTM instructions follows the RC ones and the transaction initiation result
is set on RC0 (with exception of tcheck). Currently approach is to create a
register copy from CR0 to GPR and comapring. Although this is suboptimal, since
the branch could be taken directly by comparing the CR0 value, it generates code
correctly on both test and branch and just return value. A possible future
optimization could be elimitate the MFCR instruction to branch directly.
The HTM usage requires a recently newer kernel with PPC HTM enabled. Tested on
powerpc64 and powerpc64le.
This is send along a clang patch to enabled the builtins and option switch.
[1] https://gcc.gnu.org/onlinedocs/gcc/PowerPC-Hardware-Transactional-Memory-Built-in-Functions.html
Phabricator Review: http://reviews.llvm.org/D8247
llvm-svn: 233204
diff --git a/llvm/lib/Target/PowerPC/PPCInstr64Bit.td b/llvm/lib/Target/PowerPC/PPCInstr64Bit.td
index 36479e2..183d088 100644
--- a/llvm/lib/Target/PowerPC/PPCInstr64Bit.td
+++ b/llvm/lib/Target/PowerPC/PPCInstr64Bit.td
@@ -329,6 +329,12 @@
Requires<[In64BitMode]>;
}
+def MFSPR8 : XFXForm_1<31, 339, (outs g8rc:$RT), (ins i32imm:$SPR),
+ "mfspr $RT, $SPR", IIC_SprMFSPR>;
+def MTSPR8 : XFXForm_1<31, 467, (outs), (ins i32imm:$SPR, g8rc:$RT),
+ "mtspr $SPR, $RT", IIC_SprMTSPR>;
+
+
//===----------------------------------------------------------------------===//
// 64-bit SPR manipulation instrs.