[AArch64] Fix sched model for TSV110 core. (#82343)

Accumulator operand of MADD instruction can be bypassed from another
MUL-like operation. Before this fix bypassing was incorrectly applied to
multiplier operand.

Co-authored-by: Yury Gribov <[email protected]>

Author: yugr

llvm/lib/Target/AArch64/AArch64SchedTSV110.td

@@ -419,10 +419,10 @@ def : InstRW<[TSV110Wr_12cyc_1MDU],  (instregex "^(S|U)DIVWr$")>;
 def : InstRW<[TSV110Wr_20cyc_1MDU],  (instregex "^(S|U)DIVXr$")>;
 
 def TSV110ReadMAW : SchedReadAdvance<2, [TSV110Wr_3cyc_1MDU]>;
-def : InstRW<[TSV110Wr_3cyc_1MDU, TSV110ReadMAW], (instrs MADDWrrr, MSUBWrrr)>;
+def : InstRW<[TSV110Wr_3cyc_1MDU, ReadIM, ReadIM, TSV110ReadMAW], (instrs MADDWrrr, MSUBWrrr)>;
 def TSV110ReadMAQ : SchedReadAdvance<3, [TSV110Wr_4cyc_1MDU]>;
-def : InstRW<[TSV110Wr_4cyc_1MDU, TSV110ReadMAQ], (instrs MADDXrrr, MSUBXrrr)>;
-def : InstRW<[TSV110Wr_3cyc_1MDU, TSV110ReadMAW], (instregex "(S|U)(MADDL|MSUBL)rrr")>;
+def : InstRW<[TSV110Wr_4cyc_1MDU, ReadIM, ReadIM, TSV110ReadMAQ], (instrs MADDXrrr, MSUBXrrr)>;
+def : InstRW<[TSV110Wr_3cyc_1MDU, ReadIM, ReadIM, TSV110ReadMAW], (instregex "(S|U)(MADDL|MSUBL)rrr")>;
 def : InstRW<[TSV110Wr_4cyc_1MDU], (instregex "^(S|U)MULHrr$")>;
 
 

llvm/test/tools/llvm-mca/AArch64/HiSilicon/tsv110-forwarding.s

@@ -0,0 +1,83 @@
+# NOTE: Assertions have been autogenerated by utils/update_mca_test_checks.py
+# RUN: llvm-mca -mtriple=aarch64 -mcpu=tsv110 --instruction-info=0 --resource-pressure=0 --timeline --iterations=1 < %s | FileCheck %s
+
+# LLVM-MCA-BEGIN madd nobypass
+mul  x0, x1, x2
+add  x0, x0, x1
+add  x0, x0, x1
+add  x0, x0, x1
+# LLVM-MCA-END
+
+# LLVM-MCA-BEGIN madd bypass
+mul  x0, x1, x2
+madd x0, x1, x2, x0
+madd x0, x1, x2, x0
+madd x0, x0, x0, x0
+# LLVM-MCA-END
+
+# CHECK:      [0] Code Region - madd nobypass
+
+# CHECK:      Iterations:        1
+# CHECK-NEXT: Instructions:      4
+# CHECK-NEXT: Total Cycles:      10
+# CHECK-NEXT: Total uOps:        4
+
+# CHECK:      Dispatch Width:    4
+# CHECK-NEXT: uOps Per Cycle:    0.40
+# CHECK-NEXT: IPC:               0.40
+# CHECK-NEXT: Block RThroughput: 1.0
+
+# CHECK:      Timeline view:
+# CHECK-NEXT: Index     0123456789
+
+# CHECK:      [0,0]     DeeeeER  .   mul	x0, x1, x2
+# CHECK-NEXT: [0,1]     D====eER .   add	x0, x0, x1
+# CHECK-NEXT: [0,2]     D=====eER.   add	x0, x0, x1
+# CHECK-NEXT: [0,3]     D======eER   add	x0, x0, x1
+
+# 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     1.0    1.0    0.0       mul	x0, x1, x2
+# CHECK-NEXT: 1.     1     5.0    0.0    0.0       add	x0, x0, x1
+# CHECK-NEXT: 2.     1     6.0    0.0    0.0       add	x0, x0, x1
+# CHECK-NEXT: 3.     1     7.0    0.0    0.0       add	x0, x0, x1
+# CHECK-NEXT:        1     4.8    0.3    0.0       <total>
+
+# CHECK:      [1] Code Region - madd bypass
+
+# CHECK:      Iterations:        1
+# CHECK-NEXT: Instructions:      4
+# CHECK-NEXT: Total Cycles:      13
+# CHECK-NEXT: Total uOps:        4
+
+# CHECK:      Dispatch Width:    4
+# CHECK-NEXT: uOps Per Cycle:    0.31
+# CHECK-NEXT: IPC:               0.31
+# CHECK-NEXT: Block RThroughput: 4.0
+
+# CHECK:      Timeline view:
+# CHECK-NEXT:                     012
+# CHECK-NEXT: Index     0123456789
+
+# CHECK:      [0,0]     DeeeeER   . .   mul	x0, x1, x2
+# CHECK-NEXT: [0,1]     D=eeeeER  . .   madd	x0, x1, x2, x0
+# CHECK-NEXT: [0,2]     D==eeeeER . .   madd	x0, x1, x2, x0
+# CHECK-NEXT: [0,3]     D======eeeeER   madd	x0, x0, x0, x0
+
+# 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     1.0    1.0    0.0       mul	x0, x1, x2
+# CHECK-NEXT: 1.     1     2.0    0.0    0.0       madd	x0, x1, x2, x0
+# CHECK-NEXT: 2.     1     3.0    0.0    0.0       madd	x0, x1, x2, x0
+# CHECK-NEXT: 3.     1     7.0    0.0    0.0       madd	x0, x0, x0, x0
+# CHECK-NEXT:        1     3.3    0.3    0.0       <total>