RISC-V: Enforce subword atomic LR/SC SEQ_CST

Replace LR.aq/SC.rl pairs with the SEQ_CST LR.aqrl/SC.rl pairs
recommended by table A.6 of the ISA manual.

2023-04-27 Patrick O'Neill <patrick@rivosinc.com>

gcc/ChangeLog:

	* config/riscv/sync.md: Change LR.aq/SC.rl pairs into
	sequentially consistent LR.aqrl/SC.rl pairs.

Signed-off-by: Patrick O'Neill <patrick@rivosinc.com>

diff --git a/gcc/config/riscv/sync.md b/gcc/config/riscv/sync.md
index 19274528262614958397f5811869c5aa0b7d57c9..0c83ef04607096a65fe7c9505e6b3f79804a5be4 100644 (file)
--- a/gcc/config/riscv/sync.md
+++ b/gcc/config/riscv/sync.md
@@ -109,7 +109,7 @@
   "TARGET_ATOMIC && TARGET_INLINE_SUBWORD_ATOMIC"
   {
     return "1:\;"
-          "lr.w.aq\t%0, %1\;"
+          "lr.w.aqrl\t%0, %1\;"
           "<insn>\t%5, %0, %2\;"
           "and\t%5, %5, %3\;"
           "and\t%6, %0, %4\;"
@@ -173,7 +173,7 @@
   "TARGET_ATOMIC && TARGET_INLINE_SUBWORD_ATOMIC"
   {
     return "1:\;"
-          "lr.w.aq\t%0, %1\;"
+          "lr.w.aqrl\t%0, %1\;"
           "and\t%5, %0, %2\;"
           "not\t%5, %5\;"
           "and\t%5, %5, %3\;"
@@ -278,7 +278,7 @@
   "TARGET_ATOMIC && TARGET_INLINE_SUBWORD_ATOMIC"
   {
     return "1:\;"
-          "lr.w.aq\t%0, %1\;"
+          "lr.w.aqrl\t%0, %1\;"
           "and\t%4, %0, %3\;"
           "or\t%4, %4, %2\;"
           "sc.w.rl\t%4, %4, %1\;"
@@ -443,7 +443,7 @@
   "TARGET_ATOMIC && TARGET_INLINE_SUBWORD_ATOMIC"
   {
     return "1:\;"
-          "lr.w.aq\t%0, %1\;"
+          "lr.w.aqrl\t%0, %1\;"
           "and\t%6, %0, %4\;"
           "bne\t%6, %z2, 1f\;"
           "and\t%6, %0, %5\;"