Fix tree-nrv.c ICE for direct internal functions

pass_return_slot::execute has:

	      /* Ignore internal functions without direct optabs,
		 those are expanded specially and aggregate_value_p
		 on their result might result in undesirable warnings
		 with some backends.  */
	      && (!gimple_call_internal_p (stmt)
		  || direct_internal_fn_p (gimple_call_internal_fn (stmt)))
	      && aggregate_value_p (TREE_TYPE (gimple_call_lhs (stmt)),
				    gimple_call_fndecl (stmt)))

But what the comment says applies to directly-mapped internal functions
too, since they're only used if the target supports them without a
libcall.

This was triggering an ICE on the attached testcase.  The svld3 call
is folded to an IFN_LOAD_LANES, which returns an array of vectors with
VNx48QImode.  Since no such return type can exist in C, the target hook
was complaining about an unexpected use of SVE modes.  (And we want to
keep asserting for that, so that we don't accidentally define an ABI for
an unexpected corner case.)

2020-01-09  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* tree-nrv.c (pass_return_slot::execute): Handle all internal
	functions the same way, rather than singling out those that
	aren't mapped directly to optabs.

gcc/testsuite/
	* gcc.target/aarch64/sve/acle/general/nrv_1.c: New test.

From-SVN: r280048

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e61cc9885c44d0b79621aa2e50c083b0e81380e5..a33a3518622ed8eda3b55dc34f0460e2b4926bd0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2020-01-09  Richard Sandiford  <richard.sandiford@arm.com>
+
+       * tree-nrv.c (pass_return_slot::execute): Handle all internal
+       functions the same way, rather than singling out those that
+       aren't mapped directly to optabs.
+
 2020-01-09  Richard Sandiford  <richard.sandiford@arm.com>
 
        * target.def (compatible_vector_types_p): New target hook.

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8bf435d583cffa2e907274c6d6222a9e444719da..cdb8e0df72a23e6901eda40f2d511acd32ebe04f 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2020-01-09  Richard Sandiford  <richard.sandiford@arm.com>
+
+       * gcc.target/aarch64/sve/acle/general/nrv_1.c: New test.
+
 2020-01-09  Richard Sandiford  <richard.sandiford@arm.com>
 
        * gcc.target/aarch64/sve/pcs/gnu_vectors_1.c: New test.

diff --git a/gcc/testsuite/gcc.target/aarch64/sve/acle/general/nrv_1.c b/gcc/testsuite/gcc.target/aarch64/sve/acle/general/nrv_1.c
new file mode 100644 (file)
index 0000000..360a3e4
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/acle/general/nrv_1.c
@@ -0,0 +1,17 @@
+/* { dg-options "-O -msve-vector-bits=256" } */
+
+#include <arm_sve.h>
+
+typedef uint8_t v32qi __attribute__((vector_size (32)));
+
+struct triple { v32qi v0, v1, v2; };
+
+struct triple f (uint8_t *ptr)
+{
+  svuint8x3_t data = svld3 (svptrue_b8 (), ptr);
+  struct triple res;
+  res.v0 = svget3 (data, 0);
+  res.v1 = svget3 (data, 1);
+  res.v2 = svget3 (data, 2);
+  return res;
+}

diff --git a/gcc/tree-nrv.c b/gcc/tree-nrv.c
index 2b50f878bb64dd6514a2686070f14b9918b21631..9d17a104f34c33bd979253afee819e6baaea53b8 100644 (file)
--- a/gcc/tree-nrv.c
+++ b/gcc/tree-nrv.c
@@ -378,12 +378,10 @@ pass_return_slot::execute (function *fun)
          if (stmt
              && gimple_call_lhs (stmt)
              && !gimple_call_return_slot_opt_p (stmt)
-             /* Ignore internal functions without direct optabs,
-                those are expanded specially and aggregate_value_p
-                on their result might result in undesirable warnings
-                with some backends.  */
-             && (!gimple_call_internal_p (stmt)
-                 || direct_internal_fn_p (gimple_call_internal_fn (stmt)))
+             /* Ignore internal functions, those are expanded specially
+                and aggregate_value_p on their result might result in
+                undesirable warnings with some backends.  */
+             && !gimple_call_internal_p (stmt)
              && aggregate_value_p (TREE_TYPE (gimple_call_lhs (stmt)),
                                    gimple_call_fndecl (stmt)))
            {