For sub-int types (short, char), the sign/zero extension between the
add+1 and the conditional select prevents combine from matching the
csinc pattern, so a conditional increment such as

  if (val < clipval) val++;

is emitted as cmp; add; extend; csel instead of cmp; cinc; extend.

Add two define_insn_and_split patterns that match the extended form
combine fuses and split it into a wide cinc followed by the extension,
exposing csinc2.  Computing the increment in the wider mode is safe
because extend (truncate (val + cond)) equals the sub-int-mode add.

*cinc_ext_<SHORT:mode>_<GPI:mode> handles the simple CC-mode case, where
combine fuses (cmp; add #1; extend; csel) into
(ANY_EXTEND (plus (comparison) (val))).  Saves one instruction.

*cinc_ifelse_<SHORT:mode>_<GPI:mode> handles the CC_SWP case, where
val += other precedes the increment and the extend is folded into the
compare.  The match_dup on the base makes it sound by construction: both
arms of the select extend the same value, so the false arm provably
equals the extension of the base.  Saves two instructions.

Both patterns carry a scratch register and may split before or after
reload, feeding the cinc a paradoxical lowpart of the operand whose
upper bits are dead.  Carrying the scratch (rather than gating on
can_create_pseudo_p) keeps the split valid after reload as well.

gcc/ChangeLog:

        * config/aarch64/aarch64.md (*cinc_ext_<SHORT:mode>_<GPI:mode>):
        New define_insn_and_split.
        (*cinc_ifelse_<SHORT:mode>_<GPI:mode>): Likewise.

gcc/testsuite/ChangeLog:

        * gcc.target/aarch64/cinc-subint.c: New test.
        * gcc.target/aarch64/cinc-subint-neg.c: New test.
        * gcc.target/aarch64/cinc-subint-neg-2.c: New test.
        * gcc.c-torture/execute/cond-incr-subint-1.c: New test.
        * gcc.c-torture/execute/cond-incr-subint-2.c: New test.

Signed-off-by: Philipp Tomsich <[email protected]>
---

Changes in v4:
- Produce the cinc and the extension from the split's output template
  rather than emitting them in the prepare-statements (per review feedback).
- Use gen_lowpart_SUBREG for the result's narrow view and drop the
  explanatory comments (per review feedback).

Changes in v3:
- Carry a scratch register instead of gating the split on
  can_create_pseudo_p, so a matched insn can always split: before reload
  the scratch is given a pseudo, after reload it is the allocated register
  (per review feedback).
- Feed the cinc a paradoxical lowpart of the operand rather than extending
  it, since the upper bits are dead (per review feedback).

Changes in v2:
- Reimplement with two define_insn_and_split patterns instead of four
  peephole2 patterns, following review feedback; combine now forms the
  cinc directly.  Drops the aarch64_peep_cinc_extend_p / _swp_p /
  aarch64_emit_cinc_extend helpers and their aarch64-protos.h declarations.
  The emitted instruction is cinc (via *csinc2) rather than csinc.
- Convert the codegen tests from scan-assembler to check-function-bodies.
- Move the runtime test to the generic torture suite
  (gcc.c-torture/execute), as it is not target-specific.
- Add regression tests for cases that should not be transformed
  (cinc-subint-neg-2.c, cond-incr-subint-2.c), exercising the match_dup
  soundness of the CC_SWP pattern.
- Rename the aarch64 tests to cinc-subint* (cinc, not csinc, is emitted).

 gcc/config/aarch64/aarch64.md                 |  51 +++++++
 .../execute/cond-incr-subint-1.c              | 126 ++++++++++++++++++
 .../execute/cond-incr-subint-2.c              |  65 +++++++++
 .../gcc.target/aarch64/cinc-subint-neg-2.c    |  59 ++++++++
 .../gcc.target/aarch64/cinc-subint-neg.c      |  63 +++++++++
 .../gcc.target/aarch64/cinc-subint.c          |  92 +++++++++++++
 6 files changed, 456 insertions(+)
 create mode 100644 gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-1.c
 create mode 100644 gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-2.c
 create mode 100644 gcc/testsuite/gcc.target/aarch64/cinc-subint-neg-2.c
 create mode 100644 gcc/testsuite/gcc.target/aarch64/cinc-subint-neg.c
 create mode 100644 gcc/testsuite/gcc.target/aarch64/cinc-subint.c

diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 9441e9d1eaed..5d42529dde89 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -5032,6 +5032,57 @@ (define_insn "csinc3<mode>_insn"
   [(set_attr "type" "csel")]
 )
 
+;; Conditional increment of a sub-int value: split the fused
+;; ANY_EXTEND (plus:SHORT (cond) (val)) into a wide cinc and the extension.
+(define_insn_and_split "*cinc_ext_<SHORT:mode>_<GPI:mode>"
+  [(set (match_operand:GPI 0 "register_operand" "=r")
+       (ANY_EXTEND:GPI
+         (plus:SHORT
+           (match_operand:SHORT 1 "aarch64_comparison_operation" "")
+           (match_operand:SHORT 2 "register_operand" "r"))))
+   (clobber (match_scratch:GPI 3 "=r"))]
+  ""
+  "#"
+  "&& 1"
+  [(set (match_dup 3) (plus:GPI (match_dup 1) (match_dup 2)))
+   (set (match_dup 0) (ANY_EXTEND:GPI (match_dup 4)))]
+  {
+    if (GET_CODE (operands[3]) == SCRATCH)
+      operands[3] = gen_reg_rtx (<GPI:MODE>mode);
+    operands[1] = gen_rtx_fmt_ee (GET_CODE (operands[1]), <GPI:MODE>mode,
+                                 XEXP (operands[1], 0), XEXP (operands[1], 1));
+    /* Can't use gen_lowpart_SUBREG: the operand may already be a subreg.  */
+    operands[2] = lowpart_subreg (<GPI:MODE>mode, operands[2], 
<SHORT:MODE>mode);
+    operands[4] = gen_lowpart_SUBREG (<SHORT:MODE>mode, operands[3]);
+  }
+)
+
+;; As above for the CC_SWP "val += other" variant; the match_dup on the base
+;; keeps both select arms on the same value.
+(define_insn_and_split "*cinc_ifelse_<SHORT:mode>_<GPI:mode>"
+  [(set (match_operand:GPI 0 "register_operand" "=r")
+       (if_then_else:GPI
+         (match_operand 1 "aarch64_comparison_operation" "")
+         (ANY_EXTEND:GPI (plus:SHORT (match_operand:SHORT 2 "register_operand" 
"r")
+                                     (const_int 1)))
+         (ANY_EXTEND:GPI (match_dup 2))))
+   (clobber (match_scratch:GPI 3 "=r"))]
+  ""
+  "#"
+  "&& 1"
+  [(set (match_dup 3) (plus:GPI (match_dup 1) (match_dup 2)))
+   (set (match_dup 0) (ANY_EXTEND:GPI (match_dup 4)))]
+  {
+    if (GET_CODE (operands[3]) == SCRATCH)
+      operands[3] = gen_reg_rtx (<GPI:MODE>mode);
+    operands[1] = gen_rtx_fmt_ee (GET_CODE (operands[1]), <GPI:MODE>mode,
+                                 XEXP (operands[1], 0), XEXP (operands[1], 1));
+    /* Can't use gen_lowpart_SUBREG: the operand may already be a subreg.  */
+    operands[2] = lowpart_subreg (<GPI:MODE>mode, operands[2], 
<SHORT:MODE>mode);
+    operands[4] = gen_lowpart_SUBREG (<SHORT:MODE>mode, operands[3]);
+  }
+)
+
 (define_insn "*csinv3<mode>_insn"
   [(set (match_operand:GPI 0 "register_operand" "=r")
         (if_then_else:GPI
diff --git a/gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-1.c 
b/gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-1.c
new file mode 100644
index 000000000000..956c12fa7afa
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-1.c
@@ -0,0 +1,126 @@
+/* Runtime correctness for conditional-increment of sub-int types
+   (cf. gcc.target/aarch64/cinc-subint.c, which checks the cinc codegen).
+   Not target-specific: this only validates the computed values, so it
+   lives in the generic torture suite and runs at every optimisation
+   level on every target.  */
+
+#include <limits.h>
+
+__attribute__((noinline))
+int f_short (short val, int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_schar (signed char val, int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_ushort (unsigned short val, unsigned int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_uchar (unsigned char val, unsigned int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_short_3arg (short val, short other, int clipval) {
+  val += other;
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_schar_3arg (signed char val, signed char other, int clipval) {
+  val += other;
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_ushort_3arg (unsigned short val, unsigned short other, unsigned int 
clipval) {
+  val += other;
+  if (val < clipval) val++;
+  return val;
+}
+
+__attribute__((noinline))
+int f_uchar_3arg (unsigned char val, unsigned char other, unsigned int 
clipval) {
+  val += other;
+  if (val < clipval) val++;
+  return val;
+}
+
+int
+main (void)
+{
+  /* f_short */
+  if (f_short (5, 10) != 6) __builtin_abort ();
+  if (f_short (10, 10) != 10) __builtin_abort ();
+  if (f_short (15, 10) != 15) __builtin_abort ();
+  if (f_short (9, 10) != 10) __builtin_abort ();
+  if (f_short (SHRT_MAX, SHRT_MAX) != SHRT_MAX) __builtin_abort ();
+  if (f_short (SHRT_MAX - 1, SHRT_MAX) != SHRT_MAX) __builtin_abort ();
+  if (f_short (SHRT_MIN, SHRT_MIN) != SHRT_MIN) __builtin_abort ();
+  if (f_short (SHRT_MIN, 0) != SHRT_MIN + 1) __builtin_abort ();
+  if (f_short (-5, -3) != -4) __builtin_abort ();
+  if (f_short (-3, -5) != -3) __builtin_abort ();
+
+  /* f_schar */
+  if (f_schar (5, 10) != 6) __builtin_abort ();
+  if (f_schar (10, 10) != 10) __builtin_abort ();
+  if (f_schar (SCHAR_MAX, SCHAR_MAX) != SCHAR_MAX) __builtin_abort ();
+  if (f_schar (SCHAR_MAX - 1, SCHAR_MAX) != SCHAR_MAX) __builtin_abort ();
+  if (f_schar (SCHAR_MIN, SCHAR_MIN) != SCHAR_MIN) __builtin_abort ();
+  if (f_schar (SCHAR_MIN, 0) != SCHAR_MIN + 1) __builtin_abort ();
+
+  /* f_ushort */
+  if (f_ushort (5, 10) != 6) __builtin_abort ();
+  if (f_ushort (10, 10) != 10) __builtin_abort ();
+  if (f_ushort (USHRT_MAX, USHRT_MAX) != USHRT_MAX) __builtin_abort ();
+  if (f_ushort (USHRT_MAX - 1, USHRT_MAX) != USHRT_MAX) __builtin_abort ();
+  if (f_ushort (0, 1) != 1) __builtin_abort ();
+  if (f_ushort (0, 0) != 0) __builtin_abort ();
+
+  /* f_uchar */
+  if (f_uchar (5, 10) != 6) __builtin_abort ();
+  if (f_uchar (10, 10) != 10) __builtin_abort ();
+  if (f_uchar (UCHAR_MAX, UCHAR_MAX) != UCHAR_MAX) __builtin_abort ();
+  if (f_uchar (UCHAR_MAX - 1, UCHAR_MAX) != UCHAR_MAX) __builtin_abort ();
+
+  /* f_short_3arg */
+  if (f_short_3arg (3, 4, 10) != 8) __builtin_abort ();
+  if (f_short_3arg (5, 5, 10) != 10) __builtin_abort ();
+  if (f_short_3arg (6, 5, 10) != 11) __builtin_abort ();
+  if (f_short_3arg (32000, 1000, 0) != -32535) __builtin_abort ();
+  if (f_short_3arg (-100, 50, 0) != -49) __builtin_abort ();
+  if (f_short_3arg (-100, 50, -50) != -50) __builtin_abort ();
+
+  /* f_schar_3arg */
+  if (f_schar_3arg (3, 4, 10) != 8) __builtin_abort ();
+  if (f_schar_3arg (5, 5, 10) != 10) __builtin_abort ();
+  if (f_schar_3arg (100, 100, 0) != -55) __builtin_abort ();
+  if (f_schar_3arg (-50, 20, 0) != -29) __builtin_abort ();
+
+  /* f_ushort_3arg */
+  if (f_ushort_3arg (3, 4, 10) != 8) __builtin_abort ();
+  if (f_ushort_3arg (5, 5, 10) != 10) __builtin_abort ();
+  if (f_ushort_3arg (6, 5, 10) != 11) __builtin_abort ();
+  if (f_ushort_3arg (USHRT_MAX, 1, 1) != 1) __builtin_abort ();
+  if (f_ushort_3arg (USHRT_MAX - 1, 1, USHRT_MAX) != USHRT_MAX) 
__builtin_abort ();
+
+  /* f_uchar_3arg */
+  if (f_uchar_3arg (3, 4, 10) != 8) __builtin_abort ();
+  if (f_uchar_3arg (5, 5, 10) != 10) __builtin_abort ();
+  if (f_uchar_3arg (UCHAR_MAX, 1, 1) != 1) __builtin_abort ();
+  if (f_uchar_3arg (UCHAR_MAX - 1, 1, UCHAR_MAX) != UCHAR_MAX) __builtin_abort 
();
+
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-2.c 
b/gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-2.c
new file mode 100644
index 000000000000..fb667528389b
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/cond-incr-subint-2.c
@@ -0,0 +1,65 @@
+/* Runtime regression tests for cases that should not be transformed by the
+   sub-int cinc splitters (codegen checked in
+   gcc.target/aarch64/cinc-subint-neg-2.c).  These shapes sit on the edges
+   of the *cinc_ifelse splitter's match_dup contract; two of them fold to
+   cinc and four must not.  Whether or not a shape folds, the value must be
+   the same as the unoptimised computation -- an unwanted transform would
+   change it.  Value-only, so it lives in the generic torture suite and runs
+   at every optimisation level on every target.  */
+
+__attribute__((noinline))
+int ctl_short_3arg (short val, short other, int clip)
+{ val += other; if (val < clip) val++; return val; }
+
+__attribute__((noinline))
+int diff_base (short val, short other, int clip)
+{ short inc = val + other; short alt = val - other;
+  return (inc < clip) ? (short) (inc + 1) : alt; }
+
+__attribute__((noinline))
+int inc2 (short val, short other, int clip)
+{ val += other; if (val < clip) val += 2; return val; }
+
+__attribute__((noinline))
+int dec1 (short val, short other, int clip)
+{ val += other; if (val < clip) val--; return val; }
+
+__attribute__((noinline))
+int rev (short val, short other, int clip)
+{ short s = val + other; return (s < clip) ? (int) s : (int) (short) (s + 1); }
+
+__attribute__((noinline))
+int mixed_ext (short val, short other, int clip)
+{ short s = val + other; return (s < clip) ? (int) (unsigned short) (s + 1) : 
(int) s; }
+
+struct row { short a, b; int c, ctl, diff, i2, d1, rv, mx; };
+
+static const struct row tab[] = {
+  {     3,    4,     10,      8,      8,      9,      6,      7,      8 },
+  {     5,    5,     10,     10,      0,     10,     10,     11,     10 },
+  {     6,    5,     10,     11,      1,     11,     11,     12,     11 },
+  { 32000, 1000,      0, -32535, -32535, -32534, -32537, -32536,  33001 },
+  {  -100,   50,      0,    -49,    -49,    -48,    -51,    -50,  65487 },
+  {  -100,   50,    -50,    -50,   -150,    -50,    -50,    -49,    -50 },
+  {   100,  -50,      0,     50,    150,     50,     50,     51,     50 },
+  {     0,    0,      0,      0,      0,      0,      0,      1,      0 },
+  { 32767,    1,  32767, -32767, -32767, -32766,  32767, -32768,  32769 },
+  {-32768,   -1,      0,  32767, -32767,  32767,  32767, -32768,  32767 },
+  {    10,  -20,     -5,     -9,     -9,     -8,    -11,    -10,  65527 },
+};
+
+int
+main (void)
+{
+  for (unsigned i = 0; i < sizeof (tab) / sizeof (tab[0]); i++)
+    {
+      const struct row *r = &tab[i];
+      if (ctl_short_3arg (r->a, r->b, r->c) != r->ctl) __builtin_abort ();
+      if (diff_base (r->a, r->b, r->c) != r->diff) __builtin_abort ();
+      if (inc2 (r->a, r->b, r->c) != r->i2) __builtin_abort ();
+      if (dec1 (r->a, r->b, r->c) != r->d1) __builtin_abort ();
+      if (rev (r->a, r->b, r->c) != r->rv) __builtin_abort ();
+      if (mixed_ext (r->a, r->b, r->c) != r->mx) __builtin_abort ();
+    }
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/cinc-subint-neg-2.c 
b/gcc/testsuite/gcc.target/aarch64/cinc-subint-neg-2.c
new file mode 100644
index 000000000000..2aae4a80468a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/cinc-subint-neg-2.c
@@ -0,0 +1,59 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+/* { dg-final { check-function-bodies "**" "" "" } } */
+
+/* Regression tests for cases that should not be transformed by the sub-int
+   cinc splitters (see cinc-subint.c).  The *cinc_ifelse splitter is sound
+   only because its match_dup forces both arms of the select to extend the
+   same base with the same extension.  These shapes exercise the edges of
+   that contract: only the two genuine conditional-increment shapes may fold
+   to cinc; every near miss must stay csel.  The scan-assembler-times
+   directives pin "exactly two fold, four do not", so an unwanted transform
+   (extra cinc) or a regression (missing cinc) both fail.
+   cond-incr-subint-2.c checks the values at runtime.  */
+
+/* Genuine conditional increment -> folds to cinc.  */
+/*
+** ctl_short_3arg:
+**     add     w0, w0, w1
+**     cmp     w2, w0, sxth
+**     cinc    w0, w0, gt
+**     sxth    w0, w0
+**     ret
+*/
+int ctl_short_3arg (short val, short other, int clip)
+{ val += other; if (val < clip) val++; return val; }
+
+/* +1 on the false arm: combine canonicalises (swap arms, invert the
+   condition) and folds correctly with the inverted condition.  */
+/*
+** rev:
+**     add     w0, w0, w1
+**     cmp     w2, w0, sxth
+**     cinc    w0, w0, le
+**     sxth    w0, w0
+**     ret
+*/
+int rev (short val, short other, int clip)
+{ short s = val + other; return (s < clip) ? (int) s : (int) (short) (s + 1); }
+
+/* Different base in each arm: match_dup must reject -> csel.  */
+int diff_base (short val, short other, int clip)
+{ short inc = val + other; short alt = val - other;
+  return (inc < clip) ? (short) (inc + 1) : alt; }
+
+/* Increment by two, not one -> csel.  */
+int inc2 (short val, short other, int clip)
+{ val += other; if (val < clip) val += 2; return val; }
+
+/* Decrement, not increment -> csel.  */
+int dec1 (short val, short other, int clip)
+{ val += other; if (val < clip) val--; return val; }
+
+/* Mixed extension (zero-extend one arm, sign-extend the other): the single
+   ANY_EXTEND iterator cannot match a mixed pair -> csel.  */
+int mixed_ext (short val, short other, int clip)
+{ short s = val + other; return (s < clip) ? (int) (unsigned short) (s + 1) : 
(int) s; }
+
+/* { dg-final { scan-assembler-times "\tcinc\t" 2 } } */
+/* { dg-final { scan-assembler-times "\tcsel\t" 4 } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/cinc-subint-neg.c 
b/gcc/testsuite/gcc.target/aarch64/cinc-subint-neg.c
new file mode 100644
index 000000000000..614827312d2e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/cinc-subint-neg.c
@@ -0,0 +1,63 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+/* { dg-final { check-function-bodies "**" "" "" } } */
+
+/* Negative tests for the sub-int cinc splitters in cinc-subint.c: shapes that
+   must NOT be turned into cinc.  check-function-bodies makes the expected
+   instruction explicit for each case.  */
+
+/* Increment by 2 instead of 1: not a cinc candidate -> csel.  */
+/*
+** neg_add2:
+**     sxth    w0, w0
+**     cmp     w0, w1
+**     add     w1, w0, 2
+**     sxth    w1, w1
+**     csel    w0, w0, w1, ge
+**     ret
+*/
+int neg_add2 (short val, int clipval) {
+  if (val < clipval) val += 2;
+  return val;
+}
+
+/* Decrement instead of increment: not a cinc candidate -> csel.  */
+/*
+** neg_dec:
+**     sxth    w0, w0
+**     cmp     w0, w1
+**     sub     w1, w0, #1
+**     sxth    w1, w1
+**     csel    w0, w0, w1, ge
+**     ret
+*/
+int neg_dec (short val, int clipval) {
+  if (val < clipval) val--;
+  return val;
+}
+
+/* Full-width int: combine forms cinc directly; verify no regression.  */
+/*
+** pos_fullwidth:
+**     cmp     w0, w1
+**     cinc    w0, w0, lt
+**     ret
+*/
+int pos_fullwidth (int val, int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+/* Conditional assignment (not increment): csel, not cinc.  */
+/*
+** neg_assign:
+**     sxth    w0, w0
+**     sxth    w2, w2
+**     cmp     w0, w1
+**     csel    w0, w0, w2, ge
+**     ret
+*/
+int neg_assign (short val, int clipval, short other) {
+  if (val < clipval) val = other;
+  return val;
+}
diff --git a/gcc/testsuite/gcc.target/aarch64/cinc-subint.c 
b/gcc/testsuite/gcc.target/aarch64/cinc-subint.c
new file mode 100644
index 000000000000..099895ec067a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/cinc-subint.c
@@ -0,0 +1,92 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+/* { dg-final { check-function-bodies "**" "" "" } } */
+
+/* Conditional increment of a sub-int value should use cinc, not csel.
+   For short/char the sign/zero extension between the add and the select
+   blocks combine from forming cinc; a define_insn_and_split sinks the
+   extension past the select to expose it.  */
+
+/*
+** f_short:
+**     sxth    w0, w0
+**     cmp     w0, w1
+**     cinc    w0, w0, lt
+**     sxth    w0, w0
+**     ret
+*/
+int f_short (short val, int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+/*
+** f_schar:
+**     sxtb    w0, w0
+**     cmp     w0, w1
+**     cinc    w0, w0, lt
+**     sxtb    w0, w0
+**     ret
+*/
+int f_schar (signed char val, int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+/*
+** f_ushort:
+**     and     w0, w0, 65535
+**     cmp     w0, w1
+**     cinc    w0, w0, cc
+**     and     w0, w0, 65535
+**     ret
+*/
+int f_ushort (unsigned short val, unsigned int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+/*
+** f_uchar:
+**     and     w0, w0, 255
+**     cmp     w0, w1
+**     cinc    w0, w0, cc
+**     and     w0, w0, 255
+**     ret
+*/
+int f_uchar (unsigned char val, unsigned int clipval) {
+  if (val < clipval) val++;
+  return val;
+}
+
+/* Three-argument variants where val += other precedes the conditional
+   increment.  The addition produces a full-width result, so the compare
+   uses CC_SWP mode with a folded sign/zero-extend.  */
+
+/*
+** f_short_3arg:
+**     add     w0, w0, w1
+**     cmp     w2, w0, sxth
+**     cinc    w0, w0, gt
+**     sxth    w0, w0
+**     ret
+*/
+int f_short_3arg (short val, short other, int clipval) {
+  val += other;
+  if (val < clipval) val++;
+  return val;
+}
+
+/*
+** f_schar_3arg:
+**     add     w0, w0, w1
+**     cmp     w2, w0, sxtb
+**     cinc    w0, w0, gt
+**     sxtb    w0, w0
+**     ret
+*/
+int f_schar_3arg (signed char val, signed char other, int clipval) {
+  val += other;
+  if (val < clipval) val++;
+  return val;
+}
-- 
2.34.1

base-commit: 09e74059bdb12c784570d40b28a33f22090badfe
branch: ptomsich/40-cinc-combine-splitter

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