This could be useful for library writers who want to write code variants
for fast vs. slow unaligned accesses.
We distinguish explicit -mstrict-align (1) vs. slow_unaligned_access
cpu tune param (2) for even more code divesity.
gcc/ChangeLog:
* config/riscv-c.cc (riscv_cpu_cpp_builtins):
Generate __riscv_strict_align with value 1 or 2.
* config/riscv/riscv.cc: Define riscv_user_wants_strict_align.
(riscv_option_override) Set riscv_user_wants_strict_align to
TARGET_STRICT_ALIGN.
* config/riscv/riscv.h: Declare riscv_user_wants_strict_align.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/attribute.c: Check for
__riscv_strict_align=1.
* gcc.target/riscv/predef-align-1.c: New test.
* gcc.target/riscv/predef-align-2.c: New test.
* gcc.target/riscv/predef-align-3.c: New test.
* gcc.target/riscv/predef-align-4.c: New test.
* gcc.target/riscv/predef-align-5.c: New test.
Signed-off-by: Vineet Gupta <vine...@rivosinc.com>
---
gcc/config/riscv/riscv-c.cc | 11 +++++++++++
gcc/config/riscv/riscv.cc | 9 +++++++++
gcc/config/riscv/riscv.h | 1 +
gcc/testsuite/gcc.target/riscv/attribute-4.c | 9 +++++++++
gcc/testsuite/gcc.target/riscv/predef-align-1.c | 12 ++++++++++++
gcc/testsuite/gcc.target/riscv/predef-align-2.c | 11 +++++++++++
gcc/testsuite/gcc.target/riscv/predef-align-3.c | 15 +++++++++++++++
gcc/testsuite/gcc.target/riscv/predef-align-4.c | 16 ++++++++++++++++
gcc/testsuite/gcc.target/riscv/predef-align-5.c | 16 ++++++++++++++++
9 files changed, 100 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/riscv/predef-align-1.c
create mode 100644 gcc/testsuite/gcc.target/riscv/predef-align-2.c
create mode 100644 gcc/testsuite/gcc.target/riscv/predef-align-3.c
create mode 100644 gcc/testsuite/gcc.target/riscv/predef-align-4.c
create mode 100644 gcc/testsuite/gcc.target/riscv/predef-align-5.c
diff --git a/gcc/config/riscv/riscv-c.cc b/gcc/config/riscv/riscv-c.cc
index 826ae0067bb8..47a396501d74 100644
--- a/gcc/config/riscv/riscv-c.cc
+++ b/gcc/config/riscv/riscv-c.cc
@@ -102,6 +102,17 @@ riscv_cpu_cpp_builtins (cpp_reader *pfile)
}
+ /* TARGET_STRICT_ALIGN does not cover all cases. */
+ if (riscv_slow_unaligned_access_p)
+ {
+ /* Explicit -mstruct-align preceedes cpu tune param
+ slow_unaligned_access=true. */
+ if (riscv_user_wants_strict_align)
+ builtin_define_with_int_value ("__riscv_strict_align", 1);
+ else
+ builtin_define_with_int_value ("__riscv_strict_align", 2);
+ }
+
if (TARGET_MIN_VLEN != 0)
builtin_define_with_int_value ("__riscv_v_min_vlen", TARGET_MIN_VLEN);
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 9a53999a39de..d6a40d043584 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -255,6 +255,9 @@ struct riscv_tune_info {
/* Whether unaligned accesses execute very slowly. */
bool riscv_slow_unaligned_access_p;
+/* Whether use explcitly passed -mstrict-align. */
+bool riscv_user_wants_strict_align;
+
/* Stack alignment to assume/maintain. */
unsigned riscv_stack_boundary;
@@ -6047,6 +6050,12 @@ riscv_option_override (void)
-m[no-]strict-align is left unspecified, heed -mtune's advice. */
riscv_slow_unaligned_access_p = (cpu->tune_param->slow_unaligned_access
|| TARGET_STRICT_ALIGN);
+
+ /* Make a note if user explicitly passed -mstrict-align for later
+ builtin macro generation. Can't use target_flags_explicit since
+ it is set even for -mno-strict-align. */
+ riscv_user_wants_strict_align = TARGET_STRICT_ALIGN;
+
if ((target_flags_explicit & MASK_STRICT_ALIGN) == 0
&& cpu->tune_param->slow_unaligned_access)
target_flags |= MASK_STRICT_ALIGN;
diff --git a/gcc/config/riscv/riscv.h b/gcc/config/riscv/riscv.h
index 0ab739bd6ebf..c55546656b7d 100644
--- a/gcc/config/riscv/riscv.h
+++ b/gcc/config/riscv/riscv.h
@@ -1030,6 +1030,7 @@ while (0)
#ifndef USED_FOR_TARGET
extern const enum reg_class riscv_regno_to_class[];
extern bool riscv_slow_unaligned_access_p;
+extern bool riscv_user_wants_strict_align;
extern unsigned riscv_stack_boundary;
extern unsigned riscv_bytes_per_vector_chunk;
extern poly_uint16 riscv_vector_chunks;
diff --git a/gcc/testsuite/gcc.target/riscv/attribute-4.c
b/gcc/testsuite/gcc.target/riscv/attribute-4.c
index 7c565c4963ec..ce7f1929e6a6 100644
--- a/gcc/testsuite/gcc.target/riscv/attribute-4.c
+++ b/gcc/testsuite/gcc.target/riscv/attribute-4.c
@@ -2,5 +2,14 @@
/* { dg-options "-mriscv-attribute -mstrict-align" } */
int foo()
{
+
+#if !defined(__riscv_strict_align)
+#error "__riscv_strict_align"
+#if __riscv_strict_align != 1
+#error "__riscv_strict_align != 1"
+#endif
+#endif
+
+ return 0;
}
/* { dg-final { scan-assembler ".attribute unaligned_access, 0" } } */
diff --git a/gcc/testsuite/gcc.target/riscv/predef-align-1.c
b/gcc/testsuite/gcc.target/riscv/predef-align-1.c
new file mode 100644
index 000000000000..49153a8efc20
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/predef-align-1.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-mtune=thead-c906" } */
+
+int main () {
+
+/* thead-c906 default is cpu tune param unaligned access fast. */
+#if defined(__riscv_strict_align)
+#error "__riscv_strict_align"
+#endif
+
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.target/riscv/predef-align-2.c
b/gcc/testsuite/gcc.target/riscv/predef-align-2.c
new file mode 100644
index 000000000000..b1c6ee5606e8
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/predef-align-2.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-mtune=thead-c906 -mno-strict-align" } */
+
+int main () {
+
+#if defined(__riscv_strict_align)
+#error "__riscv_strict_align"
+#endif
+
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.target/riscv/predef-align-3.c
b/gcc/testsuite/gcc.target/riscv/predef-align-3.c
new file mode 100644
index 000000000000..7a417ec8ff7e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/predef-align-3.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-mtune=thead-c906 -mstrict-align" } */
+
+int main () {
+
+#if !defined(__riscv_strict_align)
+#error "__riscv_strict_align"
+#else
+#if __riscv_strict_align != 1
+#error "__riscv_strict_align != 1"
+#endif
+#endif
+
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.target/riscv/predef-align-4.c
b/gcc/testsuite/gcc.target/riscv/predef-align-4.c
new file mode 100644
index 000000000000..a1d6da8053a4
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/predef-align-4.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-mtune=rocket" } */
+
+int main () {
+
+/* rocket default is cpu tune param unaligned access slow. */
+#if !defined(__riscv_strict_align)
+#error "__riscv_strict_align"
+#else
+#if __riscv_strict_align != 2
+#error "__riscv_strict_align != 2"
+#endif
+#endif
+
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.target/riscv/predef-align-5.c
b/gcc/testsuite/gcc.target/riscv/predef-align-5.c
new file mode 100644
index 000000000000..a8d239be9afd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/predef-align-5.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-mtune=rocket -mno-strict-align" } */
+
+int main () {
+
+/* -mno-strict-align override due to cpu tune param. */
+#if !defined(__riscv_strict_align)
+#error "__riscv_strict_align"
+#else
+#if __riscv_strict_align != 2
+#error "__riscv_strict_align != 2"
+#endif
+#endif
+
+ return 0;
+}
--
2.34.1
