[PATCH] RISC-V: Fix th.extu operands exceeding range on rv32.

[Xianmiao Qu]

The Combine Pass may generate zero_extract instructions that are out of range.
Drawing from other architectures like AArch64, we should impose restrictions
on the "*th_extu<mode>4" pattern.

gcc/
        * config/riscv/thead.md (*th_extu<mode>4): Fix th.extu
        operands exceeding range on rv32.
        * testsuite/gcc.target/riscv/xtheadbb-extu-4.c: New.
---
 gcc/config/riscv/thead.md                       |  4 +++-
 .../gcc.target/riscv/xtheadbb-extu-4.c          | 17 +++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadbb-extu-4.c

diff --git a/gcc/config/riscv/thead.md b/gcc/config/riscv/thead.md
index 2a3af76b55c2..7a76cc8cf4a9 100644
--- a/gcc/config/riscv/thead.md
+++ b/gcc/config/riscv/thead.md
@@ -85,7 +85,9 @@
        (zero_extract:GPR (match_operand:GPR 1 "register_operand" "r")
                        (match_operand 2 "const_int_operand")
                        (match_operand 3 "const_int_operand")))]
-  "TARGET_XTHEADBB"
+  "TARGET_XTHEADBB
+   && (UINTVAL (operands[2]) + UINTVAL (operands[3])
+       <= GET_MODE_BITSIZE (<MODE>mode))"
 {
   operands[2] = GEN_INT (INTVAL (operands[2]) + INTVAL (operands[3]) - 1);
   return "th.extu\t%0,%1,%2,%3";
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadbb-extu-4.c 
b/gcc/testsuite/gcc.target/riscv/xtheadbb-extu-4.c
new file mode 100644
index 000000000000..41d3fc1f5b40
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadbb-extu-4.c
@@ -0,0 +1,17 @@
+/* { dg-do compile { target { rv32 } } } */
+/* { dg-options "-march=rv32gc_xtheadbb" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-O1" "-Os" "-Og" "-Oz" } } */
+
+struct c {
+  int f : 25;
+} d;
+
+int b;
+extern unsigned int e[];
+
+void g()
+{
+  d.f = e[2] >> (b << ~4194303 + 4194332) - 58096371;
+}
+
+/* { dg-final { scan-assembler-not {th.extu\t[ax][0-9]+,[ax][0-9]+,37,13} } } 
*/
\ No newline at end of file
-- 
2.43.0