forked from OSchip/llvm-project
524f276c74
This patch moves formation of LOC-type instructions from (late) IfConversion to the early if-conversion pass, and in some cases additionally creates them directly from select instructions during DAG instruction selection. To make early if-conversion work, the patch implements the canInsertSelect / insertSelect callbacks. It also implements the commuteInstructionImpl and FoldImmediate callbacks to enable generation of the full range of LOC instructions. Finally, the patch adds support for all instructions of the load-store-on-condition-2 facility, which allows using LOC instructions also for high registers. Due to the use of the GRX32 register class to enable high registers, we now also have to handle the cases where there are still no single hardware instructions (conditional move from a low register to a high register or vice versa). These are converted back to a branch sequence after register allocation. Since the expandRAPseudos callback is not allowed to create new basic blocks, this requires a simple new pass, modelled after the ARM/AArch64 ExpandPseudos pass. Overall, this patch causes significantly more LOC-type instructions to be used, and results in a measurable performance improvement. llvm-svn: 288028 |
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AArch64 | ||
AMDGPU | ||
ARM | ||
Hexagon | ||
Lanai | ||
Mips | ||
PowerPC | ||
Sparc | ||
SystemZ | ||
X86 | ||
XCore |