ff281f7d37
This patch extends the PGO infrastructure with an option to prefer the
instrumentation of loop entry blocks.
This option is a generalization of
19fb5b467b,
and helps to cover cases where the loop exit is never executed.
An example where this can occur are event handling loops.
Note that change does NOT change the default behavior.
107 lines
2.6 KiB
LLVM
107 lines
2.6 KiB
LLVM
; RUN: rm -rf %t && split-file %s %t
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; RUN: llvm-profdata merge %t/default.proftext -o %t/default.profdata
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; RUN: opt %t/main.ll -passes=pgo-instr-use -pgo-test-profile-file=%t/default.profdata -S | FileCheck %s
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; RUN: llvm-profdata merge %t/loop_entries.proftext -o %t/loop_entries.profdata
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; RUN: opt %t/main.ll -passes=pgo-instr-use -pgo-test-profile-file=%t/loop_entries.profdata -S | FileCheck %s
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; RUN: llvm-profdata merge %t/function_entry.proftext -o %t/function_entry.profdata
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; RUN: opt %t/main.ll -passes=pgo-instr-use -pgo-test-profile-file=%t/function_entry.profdata -S | FileCheck %s
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;--- main.ll
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define i32 @test_simple_for_with_bypass(i32 %n) {
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; CHECK: define i32 @test_simple_for_with_bypass(i32 %n)
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; CHECK-SAME: !prof ![[ENTRY_COUNT:[0-9]*]]
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entry:
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; CHECK: entry:
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%mask = and i32 %n, 65535
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%skip = icmp eq i32 %mask, 0
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br i1 %skip, label %end, label %for.entry
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; CHECK: br i1 %skip, label %end, label %for.entry
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; CHECK-SAME: !prof ![[BW_FOR_BYPASS:[0-9]+]]
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for.entry:
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; CHECK: for.entry:
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br label %for.cond
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for.cond:
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; CHECK: for.cond:
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%i = phi i32 [ 0, %for.entry ], [ %inc1, %for.inc ]
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%sum = phi i32 [ 1, %for.entry ], [ %inc, %for.inc ]
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%cmp = icmp slt i32 %i, %n
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br i1 %cmp, label %for.body, label %for.end, !prof !1
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; CHECK: br i1 %cmp, label %for.body, label %for.end
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; CHECK-SAME: !prof ![[BW_FOR_COND:[0-9]+]]
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for.body:
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; CHECK: for.body:
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%inc = add nsw i32 %sum, 1
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br label %for.inc
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for.inc:
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; CHECK: for.inc:
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%inc1 = add nsw i32 %i, 1
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br label %for.cond
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for.end:
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; CHECK: for.end:
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br label %end
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end:
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; CHECK: end:
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%final_sum = phi i32 [ %sum, %for.end ], [ 0, %entry ]
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ret i32 %final_sum
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}
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!1 = !{!"branch_weights", i32 100000, i32 80}
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; CHECK: ![[ENTRY_COUNT]] = !{!"function_entry_count", i64 12}
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; CHECK: ![[BW_FOR_BYPASS]] = !{!"branch_weights", i32 4, i32 8}
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; CHECK: ![[BW_FOR_COND]] = !{!"branch_weights", i32 123456, i32 8}
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;--- default.proftext
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# :ir is the flag to indicate this is IR level profile.
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:ir
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test_simple_for_with_bypass
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# Func Hash:
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536873292337293370
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# Num Counters:
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3
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# Counter Values:
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123456
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12
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8
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;--- loop_entries.proftext
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# :ir is the flag to indicate this is IR level profile.
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:ir
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# Always instrument the loop entry blocks
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:instrument_loop_entries
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test_simple_for_with_bypass
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# Func Hash:
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536873292337293370
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# Num Counters:
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3
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# Counter Values:
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123456
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12
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8
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;--- function_entry.proftext
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# :ir is the flag to indicate this is IR level profile.
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:ir
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# Always instrument the function entry block
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:entry_first
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test_simple_for_with_bypass
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# Func Hash:
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536873292337293370
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# Num Counters:
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3
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# Counter Values:
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12
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123456
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8
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