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#!/bin/bash
if [ -z $1 ]; then
echo "Path to clang required!"
echo "Usage: update_memprof_inputs.sh /path/to/updated/clang"
exit 1
else
CLANG=$1
fi
# Allows the script to be invoked from other directories.
OUTDIR=$(dirname $(realpath -s $0))
# Note that changes in the code below which affect relative line number
# offsets of calls from their parent function can affect callsite matching in
# the LLVM IR.
cat > ${OUTDIR}/memprof.cc << EOF
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
char *foo() {
return new char[10];
}
char *foo2() {
return foo();
}
char *bar() {
return foo2();
}
char *baz() {
return foo2();
}
char *recurse(unsigned n) {
if (!n)
return foo();
return recurse(n-1);
}
int main(int argc, char **argv) {
// Test allocations with different combinations of stack contexts and
// coldness (based on lifetime, since they are all accessed a single time
// per byte via the memset).
char *a = new char[10];
char *b = new char[10];
char *c = foo();
char *d = foo();
char *e = bar();
char *f = baz();
memset(a, 0, 10);
memset(b, 0, 10);
memset(c, 0, 10);
memset(d, 0, 10);
memset(e, 0, 10);
memset(f, 0, 10);
// a and c have short lifetimes
delete[] a;
delete[] c;
// b, d, e, and f have long lifetimes and will be detected as cold by default.
sleep(200);
delete[] b;
delete[] d;
delete[] e;
delete[] f;
// Loop ensures the two calls to recurse have stack contexts that only differ
// in one level of recursion. We should get two stack contexts reflecting the
// different levels of recursion and different allocation behavior (since the
// first has a very long lifetime and the second has a short lifetime).
for (unsigned i = 0; i < 2; i++) {
char *g = recurse(i + 3);
memset(g, 0, 10);
if (!i)
sleep(200);
delete[] g;
}
return 0;
}
EOF
COMMON_FLAGS="-fuse-ld=lld -Wl,--no-rosegment -gmlt -fdebug-info-for-profiling -mno-omit-leaf-frame-pointer -fno-omit-frame-pointer -fno-optimize-sibling-calls -m64 -Wl,-build-id -no-pie"
${CLANG} ${COMMON_FLAGS} -fmemory-profile ${OUTDIR}/memprof.cc -o ${OUTDIR}/memprof.exe
env MEMPROF_OPTIONS=log_path=stdout ${OUTDIR}/memprof.exe > ${OUTDIR}/memprof.memprofraw
${CLANG} ${COMMON_FLAGS} -fprofile-generate=. \
${OUTDIR}/memprof.cc -o ${OUTDIR}/pgo.exe
env LLVM_PROFILE_FILE=${OUTDIR}/memprof_pgo.profraw ${OUTDIR}/pgo.exe
rm ${OUTDIR}/memprof.cc
rm ${OUTDIR}/pgo.exe
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