[X86] AMD Zen 3: same-reg AVX XMM VANDNPS is a zero-cycle(!) dep-breaking zero-idiom

As confirmed by exegesis measurements, and ref docs.
This commit is contained in:
Roman Lebedev 2021-05-14 13:39:37 +03:00
parent f38dcbecb6
commit fd4cbc822b
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GPG Key ID: 083C3EBB4A1689E0
2 changed files with 24 additions and 22 deletions

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@ -1535,7 +1535,8 @@ def Zn3WriteFZeroIdiom : SchedWriteVariant<[
SchedVar<NoSchedPred, [WriteFLogic]>
]>;
// NOTE: XORPSrr, XORPDrr are not zero-cycle!
def : InstRW<[Zn3WriteFZeroIdiom], (instrs VXORPSrr, VXORPDrr)>;
def : InstRW<[Zn3WriteFZeroIdiom], (instrs VXORPSrr, VXORPDrr,
VANDNPSrr)>;
def Zn3WriteFZeroIdiomY : SchedWriteVariant<[
SchedVar<MCSchedPredicate<ZeroIdiomPredicate>, [Zn3WriteZeroLatency]>,
@ -1555,7 +1556,8 @@ def : IsZeroIdiomFunction<[
ANDNPSrr ], ZeroIdiomPredicate>,
// AVX XMM Zero-idioms.
DepBreakingClass<[ VXORPSrr, VXORPDrr ], ZeroIdiomPredicate>,
DepBreakingClass<[ VXORPSrr, VXORPDrr,
VANDNPSrr ], ZeroIdiomPredicate>,
// AVX YMM Zero-idioms.
DepBreakingClass<[ VXORPSYrr, VXORPDYrr ], ZeroIdiomPredicate>,

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@ -202,13 +202,13 @@ vandnps %xmm1, %xmm0, %xmm0
# CHECK: Iterations: 10000
# CHECK-NEXT: Instructions: 20000
# CHECK-NEXT: Total Cycles: 20003
# CHECK-NEXT: Total Cycles: 3337
# CHECK-NEXT: Total uOps: 20000
# CHECK: Dispatch Width: 6
# CHECK-NEXT: uOps Per Cycle: 1.00
# CHECK-NEXT: IPC: 1.00
# CHECK-NEXT: Block RThroughput: 0.5
# CHECK-NEXT: uOps Per Cycle: 5.99
# CHECK-NEXT: IPC: 5.99
# CHECK-NEXT: Block RThroughput: 0.3
# CHECK: Instruction Info:
# CHECK-NEXT: [1]: #uOps
@ -219,17 +219,17 @@ vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: [6]: HasSideEffects (U)
# CHECK: [1] [2] [3] [4] [5] [6] Instructions:
# CHECK-NEXT: 1 1 0.25 vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: 1 0 0.17 vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: 1 1 0.25 vandnps %xmm1, %xmm0, %xmm0
# CHECK: Register File statistics:
# CHECK-NEXT: Total number of mappings created: 20000
# CHECK-NEXT: Max number of mappings used: 66
# CHECK-NEXT: Total number of mappings created: 10000
# CHECK-NEXT: Max number of mappings used: 9
# CHECK: * Register File #1 -- Zn3FpPRF:
# CHECK-NEXT: Number of physical registers: 160
# CHECK-NEXT: Total number of mappings created: 20000
# CHECK-NEXT: Max number of mappings used: 66
# CHECK-NEXT: Total number of mappings created: 10000
# CHECK-NEXT: Max number of mappings used: 9
# CHECK: * Register File #2 -- Zn3IntegerPRF:
# CHECK-NEXT: Number of physical registers: 192
@ -263,20 +263,20 @@ vandnps %xmm1, %xmm0, %xmm0
# CHECK: Resource pressure per iteration:
# CHECK-NEXT: [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12.0] [12.1] [13] [14.0] [14.1] [14.2] [15.0] [15.1] [15.2] [16.0] [16.1]
# CHECK-NEXT: - - - - - - - - 0.50 0.50 0.50 0.50 - - - - - - - - - - -
# CHECK-NEXT: - - - - - - - - 0.25 0.25 0.25 0.25 - - - - - - - - - - -
# CHECK: Resource pressure by instruction:
# CHECK-NEXT: [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12.0] [12.1] [13] [14.0] [14.1] [14.2] [15.0] [15.1] [15.2] [16.0] [16.1] Instructions:
# CHECK-NEXT: - - - - - - - - - 0.50 - 0.50 - - - - - - - - - - - vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: - - - - - - - - 0.50 - 0.50 - - - - - - - - - - - - vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: - - - - - - - - - - - - - - - - - - - - - - - vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: - - - - - - - - 0.25 0.25 0.25 0.25 - - - - - - - - - - - vandnps %xmm1, %xmm0, %xmm0
# CHECK: Timeline view:
# CHECK-NEXT: Index 0123456
# CHECK-NEXT: Index 0123
# CHECK: [0,0] DeER .. vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: [0,1] D=eER.. vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: [1,0] D==eER. vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: [1,1] D===eER vandnps %xmm1, %xmm0, %xmm0
# CHECK: [0,0] DR . vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: [0,1] DeER vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: [1,0] D--R vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: [1,1] DeER vandnps %xmm1, %xmm0, %xmm0
# CHECK: Average Wait times (based on the timeline view):
# CHECK-NEXT: [0]: Executions
@ -285,6 +285,6 @@ vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: [3]: Average time elapsed from WB until retire stage
# CHECK: [0] [1] [2] [3]
# CHECK-NEXT: 0. 2 2.0 0.5 0.0 vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: 1. 2 3.0 0.0 0.0 vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: 2 2.5 0.3 0.0 <total>
# CHECK-NEXT: 0. 2 0.0 0.0 1.0 vandnps %xmm0, %xmm0, %xmm0
# CHECK-NEXT: 1. 2 1.0 1.0 0.0 vandnps %xmm1, %xmm0, %xmm0
# CHECK-NEXT: 2 0.5 0.5 0.5 <total>