[PATCH 4/5] [ifcvt] optimize x=c ? (y op const_int) : y by RISC-V Zicond like insns

[Fei Gao <gaofei@eswincomputing.com>]

op=[PLUS, MINUS, IOR, XOR, ASHIFT, ASHIFTRT, LSHIFTRT, ROTATE, ROTATERT, AND]

Co-authored-by: Xiao Zeng<zengxiao@eswincomputing.com>

gcc/ChangeLog:

        * ifcvt.cc (noce_cond_zero_shift_op_supported): check if OP is shift like operation
        (noce_cond_zero_binary_op_supported): restructure & call noce_cond_zero_shift_op_supported
        (noce_bbs_ok_for_cond_zero_arith): add support for const_int
        (noce_try_cond_zero_arith): add support for x=c ? (y op const_int)

gcc/testsuite/ChangeLog:

        * gcc.target/riscv/zicond_ifcvt_opt.c: add TCs for x=c ? (y op const_int) : y
---
 gcc/ifcvt.cc                                  |  45 +-
 .../gcc.target/riscv/zicond_ifcvt_opt.c       | 774 +++++++++++++++++-
 2 files changed, 811 insertions(+), 8 deletions(-)

diff --git a/gcc/ifcvt.cc b/gcc/ifcvt.cc
index 29f33f956eb..b84be53ec5c 100644
--- a/gcc/ifcvt.cc
+++ b/gcc/ifcvt.cc
@@ -2910,6 +2910,20 @@ noce_try_sign_mask (struct noce_if_info *if_info)
   return true;
 }
 
+/*  Check if OP is shift-like operation supported by conditional zero
+    based if conversion, returning TRUE if satisfied otherwise FALSE.
+
+    OP is the operation to check.  */
+static bool
+noce_cond_zero_shift_op_supported (enum rtx_code op)
+{
+  if (op == ASHIFT || op == ASHIFTRT || op == LSHIFTRT || op == ROTATE
+      || op == ROTATERT)
+    return true;
+
+  return false;
+}
+
 /*  Check if OP is supported by conditional zero based if conversion,
     returning TRUE if satisfied otherwise FALSE.
 
@@ -2921,8 +2935,7 @@ noce_cond_zero_binary_op_supported (rtx op)
   enum rtx_code opcode = GET_CODE (op);
 
   if (opcode == PLUS || opcode == MINUS || opcode == IOR || opcode == XOR
-      || opcode == ASHIFT || opcode == ASHIFTRT || opcode == LSHIFTRT
-      || opcode == ROTATE || opcode == ROTATERT || opcode == AND)
+      || opcode == AND || noce_cond_zero_shift_op_supported (opcode))
     return true;
 
   return false;
@@ -3009,7 +3022,7 @@ noce_bbs_ok_for_cond_zero_arith (struct noce_if_info *if_info, rtx *common_ptr,
   if (czero_code == UNKNOWN)
     return false;
 
-  if (REG_P (bin_op1))
+  if (CONST_INT_P (bin_op1) || REG_P (bin_op1))
     *to_replace = &XEXP (bin_exp, 1);
   else if (SUBREG_P (bin_op1))
     *to_replace = &SUBREG_REG (XEXP (bin_exp, 1));
@@ -3038,6 +3051,7 @@ noce_try_cond_zero_arith (struct noce_if_info *if_info)
   enum rtx_code czero_code = UNKNOWN;
   rtx bin_exp = NULL_RTX;
   enum rtx_code bin_code = UNKNOWN;
+  rtx bin_op0 = NULL_RTX;
   rtx non_zero_op = NULL_RTX;
   rtx *to_replace = NULL;
 
@@ -3048,6 +3062,7 @@ noce_try_cond_zero_arith (struct noce_if_info *if_info)
   start_sequence ();
 
   bin_code = GET_CODE (bin_exp);
+  bin_op0 = XEXP (bin_exp, 0);
 
   if (bin_code == AND)
     {
@@ -3074,9 +3089,16 @@ noce_try_cond_zero_arith (struct noce_if_info *if_info)
     }
   else
     {
-      non_zero_op = *to_replace;
+      if (CONST_INT_P (*to_replace))
+	{
+	  non_zero_op = gen_reg_rtx (mode);
+	  noce_emit_move_insn (non_zero_op, *to_replace);
+	}
+      else
+	non_zero_op = *to_replace;
+
       /* If x is used in both input and out like x = c ? x + z : x,
-	 use a new reg to avoid modifying x  */
+	     use a new reg to avoid modifying x  */
       if (common && rtx_equal_p (common, if_info->x))
 	target = gen_reg_rtx (mode);
       else
@@ -3089,7 +3111,18 @@ noce_try_cond_zero_arith (struct noce_if_info *if_info)
 	  return false;
 	}
 
-      *to_replace = target;
+      if (CONST_INT_P (*to_replace))
+	{
+	  if (noce_cond_zero_shift_op_supported (bin_code))
+	    *to_replace = gen_rtx_SUBREG (E_QImode, target, 0);
+	  else if (SUBREG_P (bin_op0))
+	    *to_replace = gen_rtx_SUBREG (GET_MODE (bin_op0), target, 0);
+	  else
+	    *to_replace = target;
+	}
+      else
+	*to_replace = target;
+
       noce_emit_move_insn (if_info->x, a);
     }
 
diff --git a/gcc/testsuite/gcc.target/riscv/zicond_ifcvt_opt.c b/gcc/testsuite/gcc.target/riscv/zicond_ifcvt_opt.c
index d5310690539..85743e1734c 100644
--- a/gcc/testsuite/gcc.target/riscv/zicond_ifcvt_opt.c
+++ b/gcc/testsuite/gcc.target/riscv/zicond_ifcvt_opt.c
@@ -615,6 +615,616 @@ test_RotateR_eqz (unsigned long x, unsigned long y, unsigned long z,
   return x;
 }
 
+long
+test_ADD_ceqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y + 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_ADD_ceqz_x_imm (long x, long c)
+{
+  if (c)
+    x = x + 11;
+
+  return x;
+}
+
+long
+test_ADD_nez_imm (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = y + 11;
+  return x;
+}
+
+long
+test_ADD_nez_x_imm (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = x + 11;
+  return x;
+}
+
+long
+test_ADD_nez_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y + 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_ADD_nez_x_2_imm (long x, long c)
+{
+  if (!c)
+    x = x + 11;
+
+  return x;
+}
+
+long
+test_ADD_eqz_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = y + 11;
+  return x;
+}
+
+long
+test_ADD_eqz_x_2_imm (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = x + 11;
+  return x;
+}
+
+long
+test_SUB_ceqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y - 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_SUB_ceqz_x_imm (long x, long c)
+{
+  if (c)
+    x = x - 11;
+
+  return x;
+}
+
+long
+test_SUB_nez_imm (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = y - 11;
+  return x;
+}
+
+long
+test_SUB_nez_x_imm (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = x - 11;
+  return x;
+}
+
+long
+test_SUB_nez_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y - 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_SUB_nez_x_2_imm (long x, long c)
+{
+  if (!c)
+    x = x - 11;
+
+  return x;
+}
+
+long
+test_SUB_eqz_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = y - 11;
+  return x;
+}
+
+long
+test_SUB_eqz_x_2_imm (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = x - 11;
+  return x;
+}
+
+long
+test_IOR_ceqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y | 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_IOR_ceqz_x_imm (long x, long c)
+{
+  if (c)
+    x = x | 11;
+
+  return x;
+}
+
+long
+test_IOR_nez_imm (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = y | 11;
+  return x;
+}
+
+long
+test_IOR_nez_x_imm (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = x | 11;
+  return x;
+}
+
+long
+test_IOR_nez_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y | 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_IOR_nez_x_2_imm (long x, long c)
+{
+  if (!c)
+    x = x | 11;
+
+  return x;
+}
+
+long
+test_IOR_eqz_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = y | 11;
+  return x;
+}
+
+long
+test_IOR_eqz_x_2_imm (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = x | 11;
+  return x;
+}
+
+long
+test_XOR_ceqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y ^ 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_XOR_ceqz_x_imm (long x, long c)
+{
+  if (c)
+    x = x ^ 11;
+
+  return x;
+}
+
+long
+test_XOR_nez_imm (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = y ^ 11;
+  return x;
+}
+
+long
+test_XOR_nez_x_imm (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = x ^ 11;
+  return x;
+}
+
+long
+test_XOR_nez_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y ^ 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_XOR_nez_x_2_imm (long x, long c)
+{
+  if (!c)
+    x = x ^ 11;
+
+  return x;
+}
+
+long
+test_XOR_eqz_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = y ^ 11;
+  return x;
+}
+
+long
+test_XOR_eqz_x_2_imm (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = x ^ 11;
+  return x;
+}
+
+long
+test_ADD_ceqz_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = 11 + y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_ADD_ceqz_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    x = 11 + x;
+
+  return x;
+}
+
+long
+test_ADD_nez_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = 11 + y;
+  return x;
+}
+
+long
+test_ADD_nez_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = 11 + x;
+  return x;
+}
+
+long
+test_ADD_nez_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = 11 + y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_ADD_nez_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    x = 11 + x;
+
+  return x;
+}
+
+long
+test_ADD_eqz_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = 11 + y;
+  return x;
+}
+
+long
+test_ADD_eqz_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = 11 + x;
+  return x;
+}
+
+long
+test_IOR_ceqz_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = 11 | y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_IOR_ceqz_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    x = 11 | x;
+
+  return x;
+}
+
+long
+test_IOR_nez_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = 11 | y;
+  return x;
+}
+
+long
+test_IOR_nez_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = 11 | x;
+  return x;
+}
+
+long
+test_IOR_nez_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = 11 | y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_IOR_nez_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    x = 11 | x;
+
+  return x;
+}
+
+long
+test_IOR_eqz_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = 11 | y;
+  return x;
+}
+
+long
+test_IOR_eqz_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = 11 | x;
+  return x;
+}
+
+long
+test_XOR_ceqz_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = 11 ^ y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_XOR_ceqz_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    x = 11 ^ x;
+
+  return x;
+}
+
+long
+test_XOR_nez_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = 11 ^ y;
+  return x;
+}
+
+long
+test_XOR_nez_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = 11 ^ x;
+  return x;
+}
+
+long
+test_XOR_nez_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = 11 ^ y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_XOR_nez_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    x = 11 ^ x;
+
+  return x;
+}
+
+long
+test_XOR_eqz_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = 11 ^ y;
+  return x;
+}
+
+long
+test_XOR_eqz_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = 11 ^ x;
+  return x;
+}
+
+long
+test_ShiftLeft_eqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y << 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_ShiftR_eqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y >> 11;
+  else
+    x = y;
+  return x;
+}
+
+unsigned long
+test_ShiftR_logical_eqz_imm (unsigned long x, unsigned long y, unsigned long z,
+			     unsigned long c)
+{
+  if (c)
+    x = y >> 11;
+  else
+    x = y;
+  return x;
+}
+
+unsigned long
+test_RotateL_eqz_imm (unsigned long x, unsigned long y, unsigned long c)
+{
+  if (c)
+    x = (y << 11) | (y >> (64 - 11));
+  else
+    x = y;
+  return x;
+}
+
+unsigned long
+test_RotateR_eqz_imm (unsigned long x, unsigned long y, unsigned long c)
+{
+  if (c)
+    x = (y >> 11) | (y << (64 - 11));
+  else
+    x = y;
+  return x;
+}
 long
 test_AND_ceqz (long x, long y, long z, long c)
 {
@@ -774,5 +1384,165 @@ test_AND_eqz_x_2_reverse_bin_oprands (long x, long z, long c)
     x = z & x;
   return x;
 }
-/* { dg-final { scan-assembler-times {czero\.eqz} 41 } } */
-/* { dg-final { scan-assembler-times {czero\.nez} 36 } } */
+
+long
+test_AND_ceqz_imm (long x, long y, long c)
+{
+  if (c)
+    x = y & 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_AND_ceqz_x_imm (long x, long c)
+{
+  if (c)
+    x = x & 11;
+
+  return x;
+}
+
+long
+test_AND_nez_imm (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = y & 11;
+  return x;
+}
+
+long
+test_AND_nez_x_imm (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = x & 11;
+  return x;
+}
+
+long
+test_AND_nez_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y & 11;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_AND_nez_x_2_imm (long x, long c)
+{
+  if (!c)
+    x = x & 11;
+
+  return x;
+}
+
+long
+test_AND_eqz_2_imm (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = y & 11;
+  return x;
+}
+
+long
+test_AND_eqz_x_2_imm (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = x & 11;
+  return x;
+}
+
+long
+test_AND_ceqz_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = 11 & y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_AND_ceqz_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    x = 11 & x;
+
+  return x;
+}
+
+long
+test_AND_nez_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (c)
+    x = y;
+  else
+    x = 11 & y;
+  return x;
+}
+
+long
+test_AND_nez_x_imm_reverse_bin_oprands (long x, long c)
+{
+  if (c)
+    {
+    }
+  else
+    x = 11 & x;
+  return x;
+}
+
+long
+test_AND_nez_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = 11 & y;
+  else
+    x = y;
+  return x;
+}
+
+long
+test_AND_nez_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    x = 11 & x;
+
+  return x;
+}
+
+long
+test_AND_eqz_2_imm_reverse_bin_oprands (long x, long y, long c)
+{
+  if (!c)
+    x = y;
+  else
+    x = 11 & y;
+  return x;
+}
+
+long
+test_AND_eqz_x_2_imm_reverse_bin_oprands (long x, long c)
+{
+  if (!c)
+    {
+    }
+  else
+    x = 11 & x;
+  return x;
+}
+/* { dg-final { scan-assembler-times {czero\.eqz} 82 } } */
+/* { dg-final { scan-assembler-times {czero\.nez} 72 } } */
-- 
2.17.1