[PATCH dwarves 9/9] tests: Add a few clang true signature tests

[Yonghong Song <yonghong.song@linux.dev>]

Three tests are added.

Test 1: clang_parm_optimized.sh
  BTF:   char * foo(struct t * a, struct t * d);
  DWARF: char * foo(struct t * a, int b, struct t * d);
where parameber 'b' is unused.

Test 2: clang_parm_optimized_stack.sh
  BTF:   char * foo(struct t * a, struct t * d);
  DWARF: char * foo(struct t * a, int b1, int b2, int b3, int b4, int b5, int b6, struct t * d);
where parameters 'b1' to 'b6' are unused.

Test 3: clang_parm_aggregate.sh
  BTF:   long foo(long a__f1, struct t b, int i);
  DWARF: long foo(struct t a, struct t b, int i);
where the 'struct t' definition is 'struct t { long f1; long f2; };', and
a.f2 is not used in the function.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 tests/true_signatures/clang_parm_aggregate.sh | 83 ++++++++++++++++
 tests/true_signatures/clang_parm_optimized.sh | 95 +++++++++++++++++++
 .../clang_parm_optimized_stack.sh             | 95 +++++++++++++++++++
 .../gcc_true_signatures.sh                    |  0
 4 files changed, 273 insertions(+)
 create mode 100755 tests/true_signatures/clang_parm_aggregate.sh
 create mode 100755 tests/true_signatures/clang_parm_optimized.sh
 create mode 100755 tests/true_signatures/clang_parm_optimized_stack.sh
 rename tests/{ => true_signatures}/gcc_true_signatures.sh (100%)

diff --git a/tests/true_signatures/clang_parm_aggregate.sh b/tests/true_signatures/clang_parm_aggregate.sh
new file mode 100755
index 0000000..6d92701
--- /dev/null
+++ b/tests/true_signatures/clang_parm_aggregate.sh
@@ -0,0 +1,83 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
+
+outdir=
+
+fail()
+{
+	# Do not remove test dir; might be useful for analysis
+	trap - EXIT
+	if [[ -d "$outdir" ]]; then
+		echo "Test data is in $outdir"
+	fi
+	exit 1
+}
+
+cleanup()
+{
+	rm ${outdir}/*
+	rmdir $outdir
+}
+
+outdir=$(mktemp -d /tmp/clang_true.sh.XXXXXX)
+
+trap cleanup EXIT
+
+echo -n "Validation of BTF encoding of true_signatures: "
+
+clang_true="${outdir}/clang_true"
+CC=$(which clang 2>/dev/null)
+
+if [[ -z "$CC" ]]; then
+	echo "skip: clang not available"
+	exit 2
+fi
+
+cat > ${clang_true}.c << EOF
+struct t { long f1; long f2; };
+__attribute__((noinline)) static long foo(struct t a, struct t b, int i)
+{
+        return a.f1 + b.f1 + b.f2 + i;
+}
+
+struct t p1, p2;
+int i;
+int main()
+{
+        return (int)foo(p1, p2, i);
+}
+EOF
+
+CFLAGS="$CFLAGS -g -O2"
+${CC} ${CFLAGS} -o $clang_true ${clang_true}.c
+if [[ $? -ne 0 ]]; then
+	echo "Could not compile ${clang_true}.c" >& 2
+	exit 1
+fi
+LLVM_OBJCOPY=objcopy pahole -J --btf_features=+true_signature $clang_true
+if [[ $? -ne 0 ]]; then
+	echo "Could not encode BTF for $clang_true"
+	exit 1
+fi
+
+btf_optimized=$(pfunct --all --format_path=btf $clang_true |grep "foo")
+if [[ -z "$btf_optimized" ]]; then
+	echo "skip: no optimizations applied."
+	exit 2
+fi
+
+btf_cmp=$btf_optimized
+dwarf=$(pfunct --all $clang_true |grep "foo")
+
+test -n "$VERBOSE" && printf "\nBTF: $btf_optimized  DWARF: $dwarf \n"
+
+if [[ "$btf_cmp" == "$dwarf" ]]; then
+	echo "BTF and DWARF signatures should be different and they are not: BTF: $btf_optimized ; DWARF $dwarf"
+	exit 1
+else
+        echo ""
+        echo "  BTF:   $btf_optimized"
+        echo "  DWARF: $dwarf"
+fi
+echo "Ok"
+exit 0
diff --git a/tests/true_signatures/clang_parm_optimized.sh b/tests/true_signatures/clang_parm_optimized.sh
new file mode 100755
index 0000000..3022e2b
--- /dev/null
+++ b/tests/true_signatures/clang_parm_optimized.sh
@@ -0,0 +1,95 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
+
+outdir=
+
+fail()
+{
+	# Do not remove test dir; might be useful for analysis
+	trap - EXIT
+	if [[ -d "$outdir" ]]; then
+		echo "Test data is in $outdir"
+	fi
+	exit 1
+}
+
+cleanup()
+{
+	rm ${outdir}/*
+	rmdir $outdir
+}
+
+outdir=$(mktemp -d /tmp/clang_true.sh.XXXXXX)
+
+trap cleanup EXIT
+
+echo -n "Validation of BTF encoding of true_signatures: "
+
+clang_true="${outdir}/clang_true"
+CC=$(which clang 2>/dev/null)
+
+if [[ -z "$CC" ]]; then
+	echo "skip: clang not available"
+	exit 2
+fi
+
+cat > ${clang_true}.c << EOF
+struct t { int a; };
+__attribute__((noinline)) char *tar(struct t *a, struct t *d)
+{
+	if (a->a == d->a)
+		return (char *)10;
+	else
+		return (char *)0;
+}
+
+__attribute__((noinline)) static char * foo(struct t *a, int b, struct t *d)
+{
+	return tar(a, d);
+}
+
+__attribute__((noinline)) char *bar(struct t *a, struct t *d)
+{
+	return foo(a, 1, d);
+}
+
+struct t p1, p2;
+int main()
+{
+	return !!bar(&p1, &p2);
+}
+EOF
+
+CFLAGS="$CFLAGS -g -O2"
+${CC} ${CFLAGS} -o $clang_true ${clang_true}.c
+if [[ $? -ne 0 ]]; then
+	echo "Could not compile ${clang_true}.c" >& 2
+	exit 1
+fi
+LLVM_OBJCOPY=objcopy pahole -J --btf_features=+true_signature $clang_true
+if [[ $? -ne 0 ]]; then
+	echo "Could not encode BTF for $clang_true"
+	exit 1
+fi
+
+btf_optimized=$(pfunct --all --format_path=btf $clang_true |grep "foo")
+if [[ -z "$btf_optimized" ]]; then
+	echo "skip: no optimizations applied."
+	exit 2
+fi
+
+btf_cmp=$btf_optimized
+dwarf=$(pfunct --all $clang_true |grep "foo")
+
+test -n "$VERBOSE" && printf "\nBTF: $btf_optimized  DWARF: $dwarf \n"
+
+if [[ "$btf_cmp" == "$dwarf" ]]; then
+	echo "BTF and DWARF signatures should be different and they are not: BTF: $btf_optimized ; DWARF $dwarf"
+	exit 1
+else
+        echo ""
+        echo "  BTF:   $btf_optimized"
+        echo "  DWARF: $dwarf"
+fi
+echo "Ok"
+exit 0
diff --git a/tests/true_signatures/clang_parm_optimized_stack.sh b/tests/true_signatures/clang_parm_optimized_stack.sh
new file mode 100755
index 0000000..1abb96d
--- /dev/null
+++ b/tests/true_signatures/clang_parm_optimized_stack.sh
@@ -0,0 +1,95 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
+
+outdir=
+
+fail()
+{
+	# Do not remove test dir; might be useful for analysis
+	trap - EXIT
+	if [[ -d "$outdir" ]]; then
+		echo "Test data is in $outdir"
+	fi
+	exit 1
+}
+
+cleanup()
+{
+	rm ${outdir}/*
+	rmdir $outdir
+}
+
+outdir=$(mktemp -d /tmp/clang_true.sh.XXXXXX)
+
+trap cleanup EXIT
+
+echo -n "Validation of BTF encoding of true_signatures: "
+
+clang_true="${outdir}/clang_true"
+CC=$(which clang 2>/dev/null)
+
+if [[ -z "$CC" ]]; then
+	echo "skip: clang not available"
+	exit 2
+fi
+
+cat > ${clang_true}.c << EOF
+struct t { int a; };
+__attribute__((noinline)) char *tar(struct t *a, struct t *d)
+{
+        if (a->a == d->a)
+                return (char *)10;
+        else
+                return (char *)0;
+}
+
+__attribute__((noinline)) static char * foo(struct t *a, int b1, int b2, int b3, int b4, int b5, int b6, struct t *d)
+{
+        return tar(a, d);
+}
+
+__attribute__((noinline)) char *bar(struct t *a, struct t *d)
+{
+        return foo(a, 1, 2, 3, 4, 5, 6, d);
+}
+
+struct t p1, p2;
+int main()
+{
+        return !!bar(&p1, &p2);
+}
+EOF
+
+CFLAGS="$CFLAGS -g -O2"
+${CC} ${CFLAGS} -o $clang_true ${clang_true}.c
+if [[ $? -ne 0 ]]; then
+	echo "Could not compile ${clang_true}.c" >& 2
+	exit 1
+fi
+LLVM_OBJCOPY=objcopy pahole -J --btf_features=+true_signature $clang_true
+if [[ $? -ne 0 ]]; then
+	echo "Could not encode BTF for $clang_true"
+	exit 1
+fi
+
+btf_optimized=$(pfunct --all --format_path=btf $clang_true |grep "foo")
+if [[ -z "$btf_optimized" ]]; then
+	echo "skip: no optimizations applied."
+	exit 2
+fi
+
+btf_cmp=$btf_optimized
+dwarf=$(pfunct --all $clang_true |grep "foo")
+
+test -n "$VERBOSE" && printf "\nBTF: $btf_optimized  DWARF: $dwarf \n"
+
+if [[ "$btf_cmp" == "$dwarf" ]]; then
+	echo "BTF and DWARF signatures should be different and they are not: BTF: $btf_optimized ; DWARF $dwarf"
+	exit 1
+else
+        echo ""
+        echo "  BTF:   $btf_optimized"
+        echo "  DWARF: $dwarf"
+fi
+echo "Ok"
+exit 0
diff --git a/tests/gcc_true_signatures.sh b/tests/true_signatures/gcc_true_signatures.sh
similarity index 100%
rename from tests/gcc_true_signatures.sh
rename to tests/true_signatures/gcc_true_signatures.sh
-- 
2.47.3