brintos

brintos / llvm-project-archived public Read only

0
0
Text · 924 B · 57e512e Raw
29 lines · cpp
1/*2 * This file is used to test dsymutil support for call site entries with tail3 * calls (DW_AT_call_pc).4 *5 * Instructions for regenerating binaries (on Darwin/x86_64):6 *7 * 1. Copy the source to a top-level directory to work around having absolute8 *    paths in the symtab's OSO entries.9 *10 *    mkdir -p /Inputs/ && cp tail-call.c /Inputs && cd /Inputs11 *12 * 2. Compile with call site info enabled. -O2 is used to get tail call13 *    promotion.14 *15 *    clang -g -O2 tail-call.c -c -o tail-call.macho.x86_64.o16 *    clang tail-call.macho.x86_64.o -o tail-call.macho.x86_6417 *18 * 3. Copy the binaries back into the repo's Inputs directory. You'll need19 *    -oso-prepend-path=%p to link.20 */21 22volatile int x;23 24__attribute__((disable_tail_calls, noinline)) void func2() { x++; }25 26__attribute__((noinline)) void func1() { func2(); /* tail */ }27 28__attribute__((disable_tail_calls)) int main() { func1(); /* regular */ }29