[PATCH] LoongArch: Fix the problem of structure parameter passing in C++. This structure has empty structure members and less than three floating point members.
Lulu Cheng
chenglulu@loongson.cn
Wed May 24 06:04:08 GMT 2023
An empty struct type that is not non-trivial for the purposes of calls
will be treated as though it were the following C type:
struct {
char c;
};
Before this patch was added, a structure parameter containing an empty structure and
less than three floating-point members was passed through one or two floating-point
registers, while nested empty structures are ignored. Which did not conform to the
calling convention.
After adding this patch, empty structs will always be passed.
gcc/ChangeLog:
* config/loongarch/loongarch.cc (loongarch_flatten_aggregate_field):
Mark out nested empty structs.
(loongarch_pass_aggregate_in_fpr_and_gpr_p): If an empty structure exists,
increment the number of fixed-point registers required.
gcc/testsuite/ChangeLog:
* g++.target/loongarch/empty1.C: New test.
* g++.target/loongarch/empty2.C: New test.
* g++.target/loongarch/empty3.C: New test.
---
gcc/config/loongarch/loongarch.cc | 13 +++++++++++++
gcc/testsuite/g++.target/loongarch/empty1.C | 18 ++++++++++++++++++
gcc/testsuite/g++.target/loongarch/empty2.C | 20 ++++++++++++++++++++
gcc/testsuite/g++.target/loongarch/empty3.C | 19 +++++++++++++++++++
4 files changed, 70 insertions(+)
create mode 100644 gcc/testsuite/g++.target/loongarch/empty1.C
create mode 100644 gcc/testsuite/g++.target/loongarch/empty2.C
create mode 100644 gcc/testsuite/g++.target/loongarch/empty3.C
diff --git a/gcc/config/loongarch/loongarch.cc b/gcc/config/loongarch/loongarch.cc
index 7f4e0e59573..77506410501 100644
--- a/gcc/config/loongarch/loongarch.cc
+++ b/gcc/config/loongarch/loongarch.cc
@@ -321,6 +321,18 @@ loongarch_flatten_aggregate_field (const_tree type,
|| !tree_fits_uhwi_p (TYPE_SIZE (type)))
return -1;
+ if (default_is_empty_record (type))
+ {
+ if (n < 2)
+ {
+ fields[n].type = type;
+ fields[n].offset = offset;
+ return n + 1;
+ }
+ else
+ return -1;
+ }
+
for (tree f = TYPE_FIELDS (type); f; f = DECL_CHAIN (f))
if (TREE_CODE (f) == FIELD_DECL)
{
@@ -458,6 +470,7 @@ loongarch_pass_aggregate_in_fpr_and_gpr_p (const_tree type,
{
num_float += SCALAR_FLOAT_TYPE_P (fields[i].type);
num_int += INTEGRAL_TYPE_P (fields[i].type);
+ num_int += (TREE_CODE (fields[i].type) == RECORD_TYPE);
}
return num_int == 1 && num_float == 1;
diff --git a/gcc/testsuite/g++.target/loongarch/empty1.C b/gcc/testsuite/g++.target/loongarch/empty1.C
new file mode 100644
index 00000000000..059e6774158
--- /dev/null
+++ b/gcc/testsuite/g++.target/loongarch/empty1.C
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mabi=lp64d" } */
+/* { dg-final { scan-assembler-times "ld.bu\t\\\$r4,\\\$r12,0" 1 } } */
+
+struct E {};
+struct s1
+{
+ struct E {} e1;
+ float f0;
+};
+
+extern void fun (struct s1);
+
+struct s1 s1_1 = {{}, 1.0};
+void test (void)
+{
+ fun (s1_1);
+}
diff --git a/gcc/testsuite/g++.target/loongarch/empty2.C b/gcc/testsuite/g++.target/loongarch/empty2.C
new file mode 100644
index 00000000000..abf01de751a
--- /dev/null
+++ b/gcc/testsuite/g++.target/loongarch/empty2.C
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mabi=lp64d" } */
+/* { dg-final { scan-assembler-not "fld.s" } } */
+/* { dg-final { scan-assembler-not "fld.d" } } */
+
+struct E {};
+struct s1
+{
+ struct E {} e1;
+ float f0;
+ double f1;
+};
+
+extern void fun (struct s1);
+
+struct s1 s1_1 = {{}, 1.0, 2.0};
+void test (void)
+{
+ fun (s1_1);
+}
diff --git a/gcc/testsuite/g++.target/loongarch/empty3.C b/gcc/testsuite/g++.target/loongarch/empty3.C
new file mode 100644
index 00000000000..8c40963238b
--- /dev/null
+++ b/gcc/testsuite/g++.target/loongarch/empty3.C
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mabi=lp64d" } */
+/* { dg-final { scan-assembler-not "fld.d" } } */
+
+struct E {};
+struct s1
+{
+ struct E {} e1;
+ double f0;
+ double f1;
+};
+
+extern void fun (struct s1);
+
+struct s1 s1_1 = {{}, 1.0, 2.0};
+void test (void)
+{
+ fun (s1_1);
+}
--
2.31.1
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