clang/test/Profile/misexpect-branch.c

   1 // Test that misexpect detects mis-annotated branches
   2
   3 // test diagnostics are issued when profiling data mis-matches annotations
   4 // RUN: llvm-profdata merge %S/Inputs/misexpect-branch.proftext -o %t.profdata
   5 // RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=imprecise -Wmisexpect
   6 // RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=exact -Wmisexpect -debug-info-kind=line-tables-only
   7
   8 // there should be no diagnostics when the tolerance is sufficiently high, or when -Wmisexpect is not requested
   9 // RUN: %clang_cc1 %s -O2 -o - -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=foo -fdiagnostics-misexpect-tolerance=10 -Wmisexpect -debug-info-kind=line-tables-only
  10 // RUN: %clang_cc1 %s -O2 -o - -disable-llvm-passes -emit-llvm -fprofile-instrument-use-path=%t.profdata -verify=foo
  11
  12 // Ensure we emit an error when we don't use pgo with tolerance threshold
  13 // RUN: %clang_cc1 %s -O2 -o - -emit-llvm  -fdiagnostics-misexpect-tolerance=10 -Wmisexpect -debug-info-kind=line-tables-only 2>&1 | FileCheck -check-prefix=NO_PGO %s
  14
  15 // Test -fdiagnostics-misexpect-tolerance=  requires pgo profile
  16 // NO_PGO: '-fdiagnostics-misexpect-tolerance=' requires profile-guided optimization information
  17
  18 // foo-no-diagnostics
  19 #define likely(x) __builtin_expect(!!(x), 1)
  20 #define unlikely(x) __builtin_expect(!!(x), 0)
  21
  22 int foo(int);
  23 int baz(int);
  24 int buzz();
  25
  26 const int inner_loop = 100;
  27 const int outer_loop = 2000;
  28
  29 int bar() { // imprecise-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}}
  30   int rando = buzz();
  31   int x = 0;
  32   if (likely(rando % (outer_loop * inner_loop) == 0)) { // exact-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}}
  33     x = baz(rando);
  34   } else {
  35     x = foo(50);
  36   }
  37   return x;
  38 }
  39
  40 int fizz() { // imprecise-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}}
  41   int rando = buzz();
  42   int x = 0;
  43   if (unlikely(rando % (outer_loop * inner_loop) == 0)) { // exact-warning-re {{Potential performance regression from use of __builtin_expect(): Annotation was correct on {{.+}}% ({{[0-9]+ / [0-9]+}}) of profiled executions.}}
  44     x = baz(rando);
  45   } else {
  46     x = foo(50);
  47   }
  48   return x;
  49 }