dependency-breaking-cmp.s
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# NOTE: Assertions have been autogenerated by utils/update_mca_test_checks.py
# RUN: llvm-mca -mtriple=x86_64-unknown-unknown -mcpu=btver2 -timeline -timeline-max-iterations=3 -iterations=1500 < %s | FileCheck %s
# Perf stat reports an IPC of 1.97 for this block of code.
# The CMP instruction doesn't depend on the value of EAX. It can set the flags
# without having to read the inputs.
cmp %eax, %eax
cmovae %ebx, %eax
# CHECK: Iterations: 1500
# CHECK-NEXT: Instructions: 3000
# CHECK-NEXT: Total Cycles: 1504
# CHECK-NEXT: Total uOps: 3000
# CHECK: Dispatch Width: 2
# CHECK-NEXT: uOps Per Cycle: 1.99
# CHECK-NEXT: IPC: 1.99
# CHECK-NEXT: Block RThroughput: 1.0
# 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 1 0.50 cmpl %eax, %eax
# CHECK-NEXT: 1 1 0.50 cmovael %ebx, %eax
# CHECK: Resources:
# CHECK-NEXT: [0] - JALU0
# CHECK-NEXT: [1] - JALU1
# CHECK-NEXT: [2] - JDiv
# CHECK-NEXT: [3] - JFPA
# CHECK-NEXT: [4] - JFPM
# CHECK-NEXT: [5] - JFPU0
# CHECK-NEXT: [6] - JFPU1
# CHECK-NEXT: [7] - JLAGU
# CHECK-NEXT: [8] - JMul
# CHECK-NEXT: [9] - JSAGU
# CHECK-NEXT: [10] - JSTC
# CHECK-NEXT: [11] - JVALU0
# CHECK-NEXT: [12] - JVALU1
# CHECK-NEXT: [13] - JVIMUL
# CHECK: Resource pressure per iteration:
# CHECK-NEXT: [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13]
# CHECK-NEXT: 1.00 1.00 - - - - - - - - - - - -
# CHECK: Resource pressure by instruction:
# CHECK-NEXT: [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] Instructions:
# CHECK-NEXT: - 1.00 - - - - - - - - - - - - cmpl %eax, %eax
# CHECK-NEXT: 1.00 - - - - - - - - - - - - - cmovael %ebx, %eax
# CHECK: Timeline view:
# CHECK-NEXT: Index 0123456
# CHECK: [0,0] DeER .. cmpl %eax, %eax
# CHECK-NEXT: [0,1] D=eER.. cmovael %ebx, %eax
# CHECK-NEXT: [1,0] .DeER.. cmpl %eax, %eax
# CHECK-NEXT: [1,1] .D=eER. cmovael %ebx, %eax
# CHECK-NEXT: [2,0] . DeER. cmpl %eax, %eax
# CHECK-NEXT: [2,1] . D=eER cmovael %ebx, %eax
# 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. 3 1.0 1.0 0.0 cmpl %eax, %eax
# CHECK-NEXT: 1. 3 2.0 0.0 0.0 cmovael %ebx, %eax
# CHECK-NEXT: 3 1.5 0.5 0.0 <total>