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[RISCV] Rework IDiv and FDiv pipes on SiFive7 #73970

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Dec 4, 2023
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4 changes: 2 additions & 2 deletions llvm/lib/Target/RISCV/RISCVSchedSiFive7.td
Original file line number Diff line number Diff line change
Expand Up @@ -213,12 +213,12 @@ let SchedModel = SiFive7Model in {
let BufferSize = 0 in {
def SiFive7PipeA : ProcResource<1>;
def SiFive7PipeB : ProcResource<1>;
def SiFive7IDiv : ProcResource<1>; // Int Division
def SiFive7FDiv : ProcResource<1>; // FP Division/Sqrt
def SiFive7PipeV : ProcResource<1>;
}

let BufferSize = 1 in {
def SiFive7IDiv : ProcResource<1> { let Super = SiFive7PipeB; } // Int Division
def SiFive7FDiv : ProcResource<1> { let Super = SiFive7PipeB; } // FP Division/Sqrt
def SiFive7VA : ProcResource<1> { let Super = SiFive7PipeV; } // Arithmetic sequencer
def SiFive7VL : ProcResource<1> { let Super = SiFive7PipeV; } // Load sequencer
def SiFive7VS : ProcResource<1> { let Super = SiFive7PipeV; } // Store sequencer
Expand Down
65 changes: 65 additions & 0 deletions llvm/test/tools/llvm-mca/RISCV/SiFive7/div-fdiv.s
Original file line number Diff line number Diff line change
@@ -0,0 +1,65 @@
# NOTE: Assertions have been autogenerated by utils/update_mca_test_checks.py
# RUN: llvm-mca -mtriple=riscv64 -mcpu=sifive-u74 -timeline -iterations=1 < %s \
# RUN: | FileCheck %s

div a0, a1, a2
fdiv.s f1, f2, f3

# CHECK: Iterations: 1
# CHECK-NEXT: Instructions: 2
# CHECK-NEXT: Total Cycles: 67
# CHECK-NEXT: Total uOps: 2

# CHECK: Dispatch Width: 2
# CHECK-NEXT: uOps Per Cycle: 0.03
# CHECK-NEXT: IPC: 0.03
# CHECK-NEXT: Block RThroughput: 65.0

# CHECK: Instruction Info:
# CHECK-NEXT: [1]: #uOps
# CHECK-NEXT: [2]: Latency
# CHECK-NEXT: [3]: RThroughput
# CHECK-NEXT: [4]: MayLoad
# CHECK-NEXT: [5]: MayStore
# CHECK-NEXT: [6]: HasSideEffects (U)

# CHECK: [1] [2] [3] [4] [5] [6] Instructions:
# CHECK-NEXT: 1 66 65.00 div a0, a1, a2
# CHECK-NEXT: 1 27 26.00 fdiv.s ft1, ft2, ft3

# CHECK: Resources:
# CHECK-NEXT: [0] - SiFive7FDiv
# CHECK-NEXT: [1] - SiFive7IDiv
# CHECK-NEXT: [2] - SiFive7PipeA
# CHECK-NEXT: [3] - SiFive7PipeB
# CHECK-NEXT: [4] - SiFive7PipeV
# CHECK-NEXT: [5] - SiFive7VA
# CHECK-NEXT: [6] - SiFive7VL
# CHECK-NEXT: [7] - SiFive7VS

# CHECK: Resource pressure per iteration:
# CHECK-NEXT: [0] [1] [2] [3] [4] [5] [6] [7]
# CHECK-NEXT: 26.00 65.00 - 2.00 - - - -

# CHECK: Resource pressure by instruction:
# CHECK-NEXT: [0] [1] [2] [3] [4] [5] [6] [7] Instructions:
# CHECK-NEXT: - 65.00 - 1.00 - - - - div a0, a1, a2
# CHECK-NEXT: 26.00 - - 1.00 - - - - fdiv.s ft1, ft2, ft3

# CHECK: Timeline view:
# CHECK-NEXT: 0123456789 0123456789 0123456789
# CHECK-NEXT: Index 0123456789 0123456789 0123456789 0123456

# CHECK: [0,0] DeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeE div a0, a1, a2
# CHECK-NEXT: [0,1] . . . . . . . . DeeeeeeeeeeeeeeeeeeeeeeeeeeE fdiv.s ft1, ft2, ft3

# CHECK: Average Wait times (based on the timeline view):
# CHECK-NEXT: [0]: Executions
# CHECK-NEXT: [1]: Average time spent waiting in a scheduler's queue
# CHECK-NEXT: [2]: Average time spent waiting in a scheduler's queue while ready
# CHECK-NEXT: [3]: Average time elapsed from WB until retire stage

# CHECK: [0] [1] [2] [3]
# CHECK-NEXT: 0. 1 0.0 0.0 0.0 div a0, a1, a2
# CHECK-NEXT: 1. 1 0.0 0.0 0.0 fdiv.s ft1, ft2, ft3
# CHECK-NEXT: 1 0.0 0.0 0.0 <total>