loongarch64: implement NT_PRSTATUS and NT_FPREGSET regsets decoding

* src/linux/loongarch64/arch_fpregset.c: New file.
* src/linux/loongarch64/arch_fpregset.h: Likewise.
* src/linux/loongarch64/arch_prstatus_regset.c: Likewise.
* src/linux/loongarch64/arch_prstatus_regset.h: Likewise.
* src/Makefile.am (EXTRA_DIST): Add them.
* tests/ptrace.c [__loongarch__] (TRACEE_REGS_STRUCT): Define.
(print_prstatus_regset, print_fpregset) [__loongarch__]: Update
expected output.

6 files changed, 175 insertions, 1 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 4344a1ce2..dc9fd93e7 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -647,6 +647,10 @@ EXTRA_DIST =				\
 	linux/ia64/syscallent_base_nr.h	\
 	linux/ia64/userent.h		\
 	linux/loongarch64/arch_defs_.h	\
+	linux/loongarch64/arch_fpregset.c	\
+	linux/loongarch64/arch_fpregset.h	\
+	linux/loongarch64/arch_prstatus_regset.c	\
+	linux/loongarch64/arch_prstatus_regset.h	\
 	linux/loongarch64/arch_regs.c	\
 	linux/loongarch64/get_error.c	\
 	linux/loongarch64/get_scno.c	\
diff --git a/src/linux/loongarch64/arch_fpregset.c b/src/linux/loongarch64/arch_fpregset.c
new file mode 100644
index 000000000..0a5ed0a18
--- /dev/null
+++ b/src/linux/loongarch64/arch_fpregset.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2021 The strace developers.
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+static void
+arch_decode_fpregset(struct tcb *const tcp,
+		     const kernel_ulong_t addr,
+		     const kernel_ulong_t size)
+{
+	struct_fpregset regs;
+	const size_t fetch_size = MIN(sizeof(regs), size);
+
+	if (!size || size & 7) {
+		printaddr(addr);
+	} else if (!umoven_or_printaddr(tcp, addr, fetch_size, &regs)) {
+		tprint_struct_begin();
+		PRINT_FIELD_ARRAY_UPTO(regs, fpr, fetch_size / 8, tcp,
+				       print_xint_array_member);
+		if (fetch_size > offsetof(struct_fpregset, fcc)) {
+			tprint_struct_next();
+			PRINT_FIELD_X(regs, fcc);
+		}
+		if (fetch_size > offsetof(struct_fpregset, fcsr)) {
+			tprint_struct_next();
+			PRINT_FIELD_X(regs, fcsr);
+		}
+		if (size > sizeof(regs)) {
+			tprint_struct_next();
+			tprint_more_data_follows();
+		}
+		tprint_struct_end();
+	}
+}
diff --git a/src/linux/loongarch64/arch_fpregset.h b/src/linux/loongarch64/arch_fpregset.h
new file mode 100644
index 000000000..998b40f81
--- /dev/null
+++ b/src/linux/loongarch64/arch_fpregset.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2021-2022 The strace developers.
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#ifndef STRACE_ARCH_FPREGSET_H
+# define STRACE_ARCH_FPREGSET_H
+
+typedef struct user_fp_state struct_fpregset;
+
+# define HAVE_ARCH_FPREGSET 1
+
+#endif /* !STRACE_ARCH_FPREGSET_H */
diff --git a/src/linux/loongarch64/arch_prstatus_regset.c b/src/linux/loongarch64/arch_prstatus_regset.c
new file mode 100644
index 000000000..eb83c5993
--- /dev/null
+++ b/src/linux/loongarch64/arch_prstatus_regset.c
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2021-2022 The strace developers.
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+static void
+arch_decode_prstatus_regset(struct tcb *const tcp,
+			    const kernel_ulong_t addr,
+			    const kernel_ulong_t size)
+{
+	struct_prstatus_regset regs;
+	const size_t fetch_size = MIN(sizeof(regs), size);
+
+	if (!size || size & 7) {
+		printaddr(addr);
+	} else if (!umoven_or_printaddr(tcp, addr, fetch_size, &regs)) {
+		tprint_struct_begin();
+		PRINT_FIELD_ARRAY_UPTO(regs, regs,
+				       fetch_size / 8, tcp,
+				       print_xint_array_member);
+		if (fetch_size > offsetof(struct_prstatus_regset, csr_era)) {
+			tprint_struct_next();
+			PRINT_FIELD_X(regs, csr_era);
+		}
+		if (fetch_size > offsetof(struct_prstatus_regset, csr_badv)) {
+			tprint_struct_next();
+			PRINT_FIELD_X(regs, csr_badv);
+		}
+		const size_t offset_of_reserved =
+			offsetof(struct_prstatus_regset, reserved);
+		if (fetch_size > offset_of_reserved) {
+			tprint_struct_next();
+			PRINT_FIELD_ARRAY_UPTO(regs, reserved,
+					       (fetch_size - offset_of_reserved) / 8,
+					       tcp, print_xint_array_member);
+		}
+		if (size > sizeof(regs)) {
+			tprint_struct_next();
+			tprint_more_data_follows();
+		}
+		tprint_struct_end();
+	}
+}
diff --git a/src/linux/loongarch64/arch_prstatus_regset.h b/src/linux/loongarch64/arch_prstatus_regset.h
new file mode 100644
index 000000000..e7eb64b6c
--- /dev/null
+++ b/src/linux/loongarch64/arch_prstatus_regset.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2021-2022 The strace developers.
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#ifndef STRACE_ARCH_PRSTATUS_REGSET_H
+# define STRACE_ARCH_PRSTATUS_REGSET_H
+
+typedef struct user_pt_regs struct_prstatus_regset;
+
+# define HAVE_ARCH_PRSTATUS_REGSET 1
+
+#endif /* !STRACE_ARCH_PRSTATUS_REGSET_H */
diff --git a/tests/ptrace.c b/tests/ptrace.c
index e53639c1b..cd3d59c32 100644
--- a/tests/ptrace.c
+++ b/tests/ptrace.c
@@ -205,7 +205,7 @@ test_peeksiginfo(int pid, const unsigned long bad_request)
 # define TRACEE_REGS_STRUCT struct pt_regs
 #elif defined __arm__
 # define TRACEE_REGS_STRUCT struct pt_regs
-#elif defined __arm64__ || defined __aarch64__
+#elif defined __arm64__ || defined __aarch64__ || defined __loongarch__
 # define TRACEE_REGS_STRUCT struct user_pt_regs
 #elif defined __s390__ || defined __s390x__
 # define TRACEE_REGS_STRUCT s390_regs
@@ -843,11 +843,47 @@ print_prstatus_regset(const void *const rs, const size_t size)
 		PRINT_FIELD_X(*regs, cp0_cause);
 	}
 
+# elif defined __loongarch__
+
+	if (size > offsetof(TRACEE_REGS_STRUCT, regs)) {
+		const size_t len = size - offsetof(TRACEE_REGS_STRUCT, regs);
+		fputs("regs=[", stdout);
+		for (unsigned int i = 0; i < ARRAY_SIZE(regs->regs); ++i) {
+			if (len > i * sizeof(regs->regs[i])) {
+				if (i)
+					fputs(", ", stdout);
+				PRINT_VAL_X(regs->regs[i]);
+			}
+		}
+		fputs("]", stdout);
+	}
+	if (size >= offsetofend(TRACEE_REGS_STRUCT, csr_era)) {
+		fputs(", ", stdout);
+		PRINT_FIELD_X(*regs, csr_era);
+	}
+	if (size >= offsetofend(TRACEE_REGS_STRUCT, csr_badv)) {
+		fputs(", ", stdout);
+		PRINT_FIELD_X(*regs, csr_badv);
+	}
+	if (size > offsetof(TRACEE_REGS_STRUCT, reserved)) {
+		const size_t len = size - offsetof(TRACEE_REGS_STRUCT, reserved);
+		fputs(", reserved=[", stdout);
+		for (unsigned int i = 0; i < ARRAY_SIZE(regs->reserved); ++i) {
+			if (len > i * sizeof(regs->reserved[i])) {
+				if (i)
+					fputs(", ", stdout);
+				PRINT_VAL_X(regs->reserved[i]);
+			}
+		}
+		fputs("]", stdout);
+	}
+
 # endif /*
 	   __aarch64__ ||
 	   __arm64__ ||
 	   __arm__ ||
 	   __i386__ ||
+	   __loongarch__ ||
 	   __mips__ ||
 	   __powerpc64__ ||
 	   __powerpc__ ||
@@ -1085,6 +1121,8 @@ typedef struct {
 	uint64_t fpscr;
 } ppc_fpregs_struct;
 # define TRACEE_REGS_STRUCT ppc_fpregs_struct
+#elif defined __loongarch__
+# define TRACEE_REGS_STRUCT struct user_fp_state
 #endif
 
 static void
@@ -1228,8 +1266,29 @@ print_fpregset(const void *const rs, const size_t size)
 		PRINT_FIELD_X(*regs, fpscr);
 	}
 
+# elif defined __loongarch__
+
+	fputs("fpr=[", stdout);
+	for (unsigned int i = 0; i < ARRAY_SIZE(regs->fpr); ++i) {
+		if (size > i * sizeof(regs->fpr[i])) {
+			if (i)
+				fputs(", ", stdout);
+			PRINT_VAL_X(regs->fpr[i]);
+		}
+	}
+	fputs("]", stdout);
+	if (size >= offsetofend(TRACEE_REGS_STRUCT, fcc)) {
+		fputs(", ", stdout);
+		PRINT_FIELD_X(*regs, fcc);
+	}
+	if (size >= offsetofend(TRACEE_REGS_STRUCT, fcsr)) {
+		fputs(", ", stdout);
+		PRINT_FIELD_X(*regs, fcsr);
+	}
+
 # endif /*
 	   __i386__ ||
+	   __loongarch__ ||
 	   __powerpc64__ ||
 	   __powerpc__ ||
 	   __x86_64__