[gcc r16-2110] xtensa: Fix B[GE/LT]UI instructions with immediate values of 32768 or 65536 not being emitted

[Max Filippov via Gcc-cvs]

https://gcc.gnu.org/g:57da36bed1004d2b78057568176b76cb0a50d149

commit r16-2110-g57da36bed1004d2b78057568176b76cb0a50d149
Author: Takayuki 'January June' Suwa <jjsuwa_sys3...@yahoo.co.jp>
Date:   Mon Jul 7 23:40:17 2025 +0900

    xtensa: Fix B[GE/LT]UI instructions with immediate values of 32768 or 65536 
not being emitted
    
    This is because in canonicalize_comparison() in gcc/expmed.cc, the COMPARE
    rtx_cost() for the immediate values in the title does not change between
    the old and new versions.  This patch fixes that.
    
    (note: Currently, this patch only works if some constant propagation
    optimizations are enabled (-O2 or higher) or if bare large constant
    assignments are possible (-mconst16 or -mauto-litpools).  In the future
    I hope to make it work at -O1...)
    
    gcc/ChangeLog:
    
            * config/xtensa/xtensa.cc (xtensa_b4const_or_zero):
            Remove.
            (xtensa_b4const): Add a case where the value is 0, and rename
            to xtensa_b4const_or_zero.
            (xtensa_rtx_costs): Fix to also consider the result of
            xtensa_b4constu().
    
    gcc/testsuite/ChangeLog:
    
            * gcc.target/xtensa/BGEUI-BLTUI-32k-64k.c: New.

Diff:
---
 gcc/config/xtensa/xtensa.cc                           | 17 +++++------------
 gcc/testsuite/gcc.target/xtensa/BGEUI-BLTUI-32k-64k.c | 19 +++++++++++++++++++
 2 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/gcc/config/xtensa/xtensa.cc b/gcc/config/xtensa/xtensa.cc
index 8c43a69f4cd9..b75cec13b28a 100644
--- a/gcc/config/xtensa/xtensa.cc
+++ b/gcc/config/xtensa/xtensa.cc
@@ -423,12 +423,13 @@ xtensa_uimm8x4 (HOST_WIDE_INT v)
 }
 
 
-static bool
-xtensa_b4const (HOST_WIDE_INT v)
+bool
+xtensa_b4const_or_zero (HOST_WIDE_INT v)
 {
   switch (v)
     {
     case -1:
+    case 0:
     case 1:
     case 2:
     case 3:
@@ -450,15 +451,6 @@ xtensa_b4const (HOST_WIDE_INT v)
 }
 
 
-bool
-xtensa_b4const_or_zero (HOST_WIDE_INT v)
-{
-  if (v == 0)
-    return true;
-  return xtensa_b4const (v);
-}
-
-
 bool
 xtensa_b4constu (HOST_WIDE_INT v)
 {
@@ -4512,7 +4504,8 @@ xtensa_rtx_costs (rtx x, machine_mode mode, int 
outer_code,
            }
          break;
        case COMPARE:
-         if ((INTVAL (x) == 0) || xtensa_b4const (INTVAL (x)))
+         if (xtensa_b4const_or_zero (INTVAL (x))
+             || xtensa_b4constu (INTVAL (x)))
            {
              *total = 0;
              return true;
diff --git a/gcc/testsuite/gcc.target/xtensa/BGEUI-BLTUI-32k-64k.c 
b/gcc/testsuite/gcc.target/xtensa/BGEUI-BLTUI-32k-64k.c
new file mode 100644
index 000000000000..05873b896896
--- /dev/null
+++ b/gcc/testsuite/gcc.target/xtensa/BGEUI-BLTUI-32k-64k.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+extern void foo(void);
+
+void BGEUI_test(unsigned int a)
+{
+  if (a < 32768U)
+    foo();
+}
+
+void BLTUI_test(unsigned int a)
+{
+  if (a >= 65536U)
+    foo();
+}
+
+/* { dg-final { scan-assembler-times "bgeui" 1 } } */
+/* { dg-final { scan-assembler-times "bltui" 1 } } */