[llvm] [llvm-mca] Account for AcquireAtCycles in llvm-mca (PR #80742)

[Wang Pengcheng via llvm-commits]

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@@ -37,13 +37,13 @@ vle64.v v1, (a1)
 
 # CHECK:      Iterations:        1
 # CHECK-NEXT: Instructions:      26
-# CHECK-NEXT: Total Cycles:      234
+# CHECK-NEXT: Total Cycles:      211
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wangpc-pp wrote:

I think `llvm-mca` has over estimated the cycles before. With this change, the cycles of RVV instrcctions should reduce by 1 cycle (for SiFive7VCQ), so here the total cycles reduce 23 cycles (there are 24 RVV instrcutions and extra 1 cycle for first RVV instruction?).

https://github.com/llvm/llvm-project/pull/80742