[PATCH] D139135: [RISCV] Teach RISCVMatInt to prefer li+slli over lui+addi(w) for compressibility.

[Craig Topper via Phabricator via llvm-commits]

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With C extension, li with a 6 bit immediate followed by slli is 4 bytes.
The lui+addi(w) sequence is at least 6 bytes.

The two sequences probably have similar execution latency. The exception
being if the target supports lui+addi(w) macrofusion.

Since the execution latency is probably the same I didn't restrict
this to C extension.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D139135

Files:
  llvm/lib/Target/RISCV/MCTargetDesc/RISCVMatInt.cpp
  llvm/test/CodeGen/RISCV/calling-conv-half.ll
  llvm/test/CodeGen/RISCV/i32-icmp.ll
  llvm/test/CodeGen/RISCV/i64-icmp.ll
  llvm/test/CodeGen/RISCV/macro-fusion-lui-addi.ll
  llvm/test/CodeGen/RISCV/mul.ll
  llvm/test/CodeGen/RISCV/pr58511.ll
  llvm/test/CodeGen/RISCV/rv32zbs.ll
  llvm/test/CodeGen/RISCV/rv64zbs.ll
  llvm/test/CodeGen/RISCV/rvv/active_lane_mask.ll
  llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll
  llvm/test/CodeGen/RISCV/rvv/large-rvv-stack-size.mir
  llvm/test/CodeGen/RISCV/rvv/vscale-power-of-two.ll
  llvm/test/MC/RISCV/rv32c-aliases-valid.s
  llvm/test/MC/RISCV/rv32i-aliases-valid.s
  llvm/test/MC/RISCV/rv64c-aliases-valid.s
  llvm/test/MC/RISCV/rv64i-aliases-valid.s

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