This patch handles the cases when subreg:QI of a CONST or LABEL_REF is to be
moved to a QImode register. The original patch only handled SYMBOL_REFs.
OK for trunk and backport?
Johann
--
gcc/
PR target/71103
* config/avr/avr.md (movqi): Handle loading subreg:qi (const).
gcc/testsuite/
PR target/71103
* gcc.target/avr/torture/pr71103-2.c: New test.
Index: config/avr/avr.md
===
--- config/avr/avr.md (revision 237472)
+++ config/avr/avr.md (working copy)
@@ -638,16 +638,24 @@
rtx dest = operands[0];
rtx src = avr_eval_addr_attrib (operands[1]);
-if (SUBREG_P(src) && (GET_CODE(XEXP(src,0)) == SYMBOL_REF) &&
-can_create_pseudo_p())
- {
-rtx symbol_ref = XEXP(src, 0);
-XEXP (src, 0) = copy_to_mode_reg (GET_MODE(symbol_ref), symbol_ref);
- }
-
if (avr_mem_flash_p (dest))
DONE;
+if (QImode == mode
+&& SUBREG_P (src)
+&& CONSTANT_ADDRESS_P (SUBREG_REG (src)))
+{
+// store_bitfield may want to store a SYMBOL_REF or CONST in a
+// structure that's represented as PSImode. As the upper 16 bits
+// of PSImode cannot be expressed as an HImode subreg, the rhs is
+// decomposed into QImode (word_mode) subregs of SYMBOL_REF,
+// CONST or LABEL_REF; cf. PR71103.
+
+rtx const_addr = SUBREG_REG (src);
+operands[1] = src = copy_rtx (src);
+SUBREG_REG (src) = copy_to_mode_reg (GET_MODE (const_addr), const_addr);
+ }
+
/* One of the operands has to be in a register. */
if (!register_operand (dest, mode)
&& !reg_or_0_operand (src, mode))
Index: testsuite/gcc.target/avr/torture/pr71103-2.c
===
--- testsuite/gcc.target/avr/torture/pr71103-2.c (nonexistent)
+++ testsuite/gcc.target/avr/torture/pr71103-2.c (working copy)
@@ -0,0 +1,118 @@
+/* Use -g0 so that this test case doesn't just fail because
+ of PR52472. */
+
+/* { dg-do compile } */
+/* { dg-options "-std=gnu99 -g0" } */
+
+struct S12
+{
+ char c;
+ const char *p;
+};
+
+struct S12f
+{
+ char c;
+ struct S12f (*f)(void);
+};
+
+struct S12labl
+{
+ char c;
+ void **labl;
+};
+
+struct S121
+{
+ char c;
+ const char *p;
+ char d;
+};
+
+const char str[5] = "abcd";
+
+struct S12 test_S12_0 (void)
+{
+ struct S12 s;
+ s.c = 'A';
+ s.p = str;
+ return s;
+}
+
+struct S12 test_S12_4 (void)
+{
+ struct S12 s;
+ s.c = 'A';
+ s.p = str + 4;
+ return s;
+}
+
+struct S12f test_S12f (void)
+{
+ struct S12f s;
+ s.c = 'A';
+ s.f = test_S12f;
+ return s;
+}
+
+struct S121 test_S121 (void)
+{
+ struct S121 s;
+ s.c = 'c';
+ s.p = str + 4;
+ s.d = 'd';
+ return s;
+}
+
+extern void use_S12lab (struct S12labl*);
+
+struct S12labl test_S12lab (void)
+{
+ struct S12labl s;
+labl:;
+ s.c = 'A';
+ s.labl = &
+ return s;
+}
+
+#ifdef __MEMX
+
+struct S13
+{
+ char c;
+ const __memx char *p;
+};
+
+const __memx char str_x[] = "abcd";
+
+struct S13 test_S13_0 (void)
+{
+ struct S13 s;
+ s.c = 'A';
+ s.p = str_x;
+ return s;
+}
+
+struct S13 test_S13_4a (void)
+{
+ struct S13 s;
+ s.c = 'A';
+ s.p = str_x + 4;
+ return s;
+}
+
+#ifdef __FLASH1
+
+const __flash1 char str_1[] = "abcd";
+
+struct S13 test_13_4b (void)
+{
+ struct S13 s;
+ s.c = 'A';
+ s.p = str_1 + 4;
+ return s;
+}
+
+#endif /* have __flash1 */
+#endif /* have __memx */
+