From 3e04b6f6ba568e6183e8aa8223d4156234503843 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Fri, 26 Apr 2024 15:59:11 +0800
Subject: [PATCH] LoongArch: Add constraints for bit string operation
 define_insn_and_split's [PR114861]

Without the constrants, the compiler attempts to use a stack slot as the
target, causing an ICE building the kernel with -Os:

    drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c:3144:1:
    error: could not split insn
    (insn:TI 1764 67 1745
      (set (mem/c:DI (reg/f:DI 3 $r3) [707 %sfp+-80 S8 A64])
           (and:DI (reg/v:DI 28 $r28 [orig:422 raster_config ] [422])
                   (const_int -50331649 [0xfffffffffcffffff])))
      "drivers/gpu/drm/amd/amdgpu/gfx_v6_0.c":1386:21 111
      {*bstrins_di_for_mask}
      (nil))

Add these constrants to fix the issue.

gcc/ChangeLog:

	PR target/114861
	* config/loongarch/loongarch.md (bstrins_<mode>_for_mask): Add
	constraints for operands.
	(bstrins_<mode>_for_ior_mask): Likewise.

gcc/testsuite/ChangeLog:

	PR target/114861
	* gcc.target/loongarch/pr114861.c: New test.

(cherry picked from commit 140124ad54eef88ca87909f63aedc8aaeacefc65)
---
 gcc/config/loongarch/loongarch.md             | 16 ++++----
 gcc/testsuite/gcc.target/loongarch/pr114861.c | 39 +++++++++++++++++++
 2 files changed, 47 insertions(+), 8 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/loongarch/pr114861.c

diff --git a/gcc/config/loongarch/loongarch.md b/gcc/config/loongarch/loongarch.md
index a316c8fb820..5c80c169cbf 100644
--- a/gcc/config/loongarch/loongarch.md
+++ b/gcc/config/loongarch/loongarch.md
@@ -1543,9 +1543,9 @@
    (set_attr "mode" "<MODE>")])
 
 (define_insn_and_split "*bstrins_<mode>_for_mask"
-  [(set (match_operand:GPR 0 "register_operand")
-	(and:GPR (match_operand:GPR 1 "register_operand")
-		 (match_operand:GPR 2 "ins_zero_bitmask_operand")))]
+  [(set (match_operand:GPR 0 "register_operand" "=r")
+	(and:GPR (match_operand:GPR 1 "register_operand" "r")
+		 (match_operand:GPR 2 "ins_zero_bitmask_operand" "i")))]
   ""
   "#"
   ""
@@ -1563,11 +1563,11 @@
   })
 
 (define_insn_and_split "*bstrins_<mode>_for_ior_mask"
-  [(set (match_operand:GPR 0 "register_operand")
-	(ior:GPR (and:GPR (match_operand:GPR 1 "register_operand")
-                          (match_operand:GPR 2 "const_int_operand"))
-		 (and:GPR (match_operand:GPR 3 "register_operand")
-			  (match_operand:GPR 4 "const_int_operand"))))]
+  [(set (match_operand:GPR 0 "register_operand" "=r")
+	(ior:GPR (and:GPR (match_operand:GPR 1 "register_operand" "r")
+			  (match_operand:GPR 2 "const_int_operand" "i"))
+		 (and:GPR (match_operand:GPR 3 "register_operand" "r")
+			  (match_operand:GPR 4 "const_int_operand" "i"))))]
   "loongarch_pre_reload_split ()
    && loongarch_use_bstrins_for_ior_with_mask (<MODE>mode, operands)"
   "#"
diff --git a/gcc/testsuite/gcc.target/loongarch/pr114861.c b/gcc/testsuite/gcc.target/loongarch/pr114861.c
new file mode 100644
index 00000000000..e6507c406b9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/loongarch/pr114861.c
@@ -0,0 +1,39 @@
+/* PR114861: ICE building the kernel with -Os
+   Reduced from linux/fs/ntfs3/attrib.c at revision c942a0cd3603.  */
+/* { dg-do compile } */
+/* { dg-options "-Os -march=loongarch64 -msoft-float -mabi=lp64s" } */
+
+long evcn, attr_collapse_range_vbo, attr_collapse_range_bytes;
+unsigned short flags;
+int attr_collapse_range_ni_0_0;
+int *attr_collapse_range_mi;
+unsigned attr_collapse_range_svcn, attr_collapse_range_vcn1;
+void ni_insert_nonresident (unsigned, unsigned short, int **);
+int mi_pack_runs (int);
+int
+attr_collapse_range (void)
+{
+  _Bool __trans_tmp_1;
+  int run = attr_collapse_range_ni_0_0;
+  unsigned evcn1, vcn, end;
+  short a_flags = flags;
+  __trans_tmp_1 = flags & (32768 | 1);
+  if (__trans_tmp_1)
+    return 2;
+  vcn = attr_collapse_range_vbo;
+  end = attr_collapse_range_bytes;
+  evcn1 = evcn;
+  for (;;)
+    if (attr_collapse_range_svcn >= end)
+      {
+        unsigned eat, next_svcn = mi_pack_runs (42);
+        attr_collapse_range_vcn1 = (vcn ? vcn : attr_collapse_range_svcn);
+        eat = (0 < end) - attr_collapse_range_vcn1;
+        mi_pack_runs (run - eat);
+        if (next_svcn + eat)
+          ni_insert_nonresident (evcn1 - eat - next_svcn, a_flags,
+                                 &attr_collapse_range_mi);
+      }
+    else
+      return 42;
+}