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About the unnamed insn defined in the machine.md
- From: "redriver jiang" <jiangpeople at gmail dot com>
- To: gcc at gcc dot gnu dot org
- Date: Sat, 3 Mar 2007 22:24:37 +0800
- Subject: About the unnamed insn defined in the machine.md
Hello, recently I am porting the GCC backend to a DSP. The GCC
Internals document says that the unnamed insns are used to translate
RTL insns to the assembler insns, but I find that the unnamed insn
patterns can be used in combine phase to combine insns by reading the
"*arith_shiftsi" insn pattern in arm.md file..This "*arith_shiftsi"
insn pattern is used to combine the "plus insn" and "shift insn" into
"add rd,Rn,rm,shift immediate_operand".Is my understanding correct?