1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-26 12:43:36 +01:00

[X86] AMD Zen 3: same-reg SSE XMM XORPD is a 1-cycle(!) dep-breaking zero-idiom

Same as with it's float friend, unlike their AVX versions.
As confirmed by exegesis, and ref docs.
This commit is contained in:
Roman Lebedev 2021-05-14 11:24:22 +03:00
parent ada20786f6
commit 456286cdbe
2 changed files with 19 additions and 19 deletions

View File

@ -1534,7 +1534,7 @@ def Zn3WriteFZeroIdiom : SchedWriteVariant<[
SchedVar<MCSchedPredicate<ZeroIdiomPredicate>, [Zn3WriteZeroLatency]>,
SchedVar<NoSchedPred, [WriteFLogic]>
]>;
// NOTE: XORPSrr is not zero-cycle!
// NOTE: XORPSrr, XORPDrr are not zero-cycle!
def : InstRW<[Zn3WriteFZeroIdiom], (instrs VXORPSrr)>;
def Zn3WriteFZeroIdiomY : SchedWriteVariant<[
@ -1551,7 +1551,7 @@ def : IsZeroIdiomFunction<[
SUB64rr, SUB64rr_REV ], ZeroIdiomPredicate>,
// SSE XMM Zero-idioms.
DepBreakingClass<[ XORPSrr ], ZeroIdiomPredicate>,
DepBreakingClass<[ XORPSrr, XORPDrr ], ZeroIdiomPredicate>,
// AVX XMM Zero-idioms.
DepBreakingClass<[ VXORPSrr ], ZeroIdiomPredicate>,

View File

@ -106,12 +106,12 @@ xorpd %xmm0, %xmm1
# CHECK: Iterations: 10000
# CHECK-NEXT: Instructions: 20000
# CHECK-NEXT: Total Cycles: 20003
# CHECK-NEXT: Total Cycles: 5004
# CHECK-NEXT: Total uOps: 20000
# CHECK: Dispatch Width: 6
# CHECK-NEXT: uOps Per Cycle: 1.00
# CHECK-NEXT: IPC: 1.00
# CHECK-NEXT: uOps Per Cycle: 4.00
# CHECK-NEXT: IPC: 4.00
# CHECK-NEXT: Block RThroughput: 0.5
# CHECK: Instruction Info:
@ -127,13 +127,13 @@ xorpd %xmm0, %xmm1
# CHECK-NEXT: 1 1 0.25 xorpd %xmm0, %xmm1
# 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: 37
# 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: 37
# CHECK: * Register File #2 -- Zn3IntegerPRF:
# CHECK-NEXT: Number of physical registers: 192
@ -171,16 +171,16 @@ xorpd %xmm0, %xmm1
# 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 - - - - - - - - - - - xorpd %xmm1, %xmm1
# CHECK-NEXT: - - - - - - - - 0.50 - 0.50 - - - - - - - - - - - - xorpd %xmm0, %xmm1
# CHECK-NEXT: - - - - - - - - - 0.50 0.25 0.25 - - - - - - - - - - - xorpd %xmm1, %xmm1
# CHECK-NEXT: - - - - - - - - 0.50 - 0.25 0.25 - - - - - - - - - - - xorpd %xmm0, %xmm1
# CHECK: Timeline view:
# CHECK-NEXT: Index 0123456
# CHECK-NEXT: Index 01234
# CHECK: [0,0] DeER .. xorpd %xmm1, %xmm1
# CHECK-NEXT: [0,1] D=eER.. xorpd %xmm0, %xmm1
# CHECK-NEXT: [1,0] D==eER. xorpd %xmm1, %xmm1
# CHECK-NEXT: [1,1] D===eER xorpd %xmm0, %xmm1
# CHECK: [0,0] DeER. xorpd %xmm1, %xmm1
# CHECK-NEXT: [0,1] D=eER xorpd %xmm0, %xmm1
# CHECK-NEXT: [1,0] DeE-R xorpd %xmm1, %xmm1
# CHECK-NEXT: [1,1] D=eER xorpd %xmm0, %xmm1
# CHECK: Average Wait times (based on the timeline view):
# CHECK-NEXT: [0]: Executions
@ -189,6 +189,6 @@ xorpd %xmm0, %xmm1
# 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 xorpd %xmm1, %xmm1
# CHECK-NEXT: 1. 2 3.0 0.0 0.0 xorpd %xmm0, %xmm1
# CHECK-NEXT: 2 2.5 0.3 0.0 <total>
# CHECK-NEXT: 0. 2 1.0 1.0 0.5 xorpd %xmm1, %xmm1
# CHECK-NEXT: 1. 2 2.0 0.0 0.0 xorpd %xmm0, %xmm1
# CHECK-NEXT: 2 1.5 0.5 0.3 <total>