Apparently, Qt source uses these two builtins. As the removal brings
much pain, I'd like to commit the following patch to restore
__builtin_clzs and __builtin_ctzs on gcc-6 branch.
2016-12-14 Uros Bizjak <ubiz...@gmail.com>
PR target/59874
* config/i386/i386.c (enum ix86_builtins): Add IX86_BUILTIN_CLZS
and IX86_BUILTIN_CTZS.
(bdesc_args): Add __builtin_clzs and __builtin_ctzs.
(ix86_fold_builtin): Handle IX86_BUILTIN_CTZS and IX86_BUILTIN_CLZS.
Bootstrapped and regression tested on x86_64-linux-gnu.
I have also checked that patched gcc emits the same code as before.
Uros.
Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c (revision 243649)
+++ config/i386/i386.c (working copy)
@@ -32396,6 +32396,7 @@ enum ix86_builtins
/* LZCNT */
IX86_BUILTIN_LZCNT16,
+ IX86_BUILTIN_CLZS,
IX86_BUILTIN_LZCNT32,
IX86_BUILTIN_LZCNT64,
@@ -32422,6 +32423,7 @@ enum ix86_builtins
IX86_BUILTIN_BEXTR32,
IX86_BUILTIN_BEXTR64,
IX86_BUILTIN_TZCNT16,
+ IX86_BUILTIN_CTZS,
IX86_BUILTIN_TZCNT32,
IX86_BUILTIN_TZCNT64,
@@ -33813,6 +33815,8 @@ static const struct builtin_description bdesc_args
/* LZCNT */
{ OPTION_MASK_ISA_LZCNT, CODE_FOR_lzcnt_hi, "__builtin_ia32_lzcnt_u16",
IX86_BUILTIN_LZCNT16, UNKNOWN, (int) UINT16_FTYPE_UINT16 },
+ /* Same as above, for backward compatibility. */
+ { OPTION_MASK_ISA_LZCNT, CODE_FOR_lzcnt_hi, "__builtin_clzs",
IX86_BUILTIN_CLZS, UNKNOWN, (int) UINT16_FTYPE_UINT16 },
{ OPTION_MASK_ISA_LZCNT, CODE_FOR_lzcnt_si, "__builtin_ia32_lzcnt_u32",
IX86_BUILTIN_LZCNT32, UNKNOWN, (int) UINT_FTYPE_UINT },
{ OPTION_MASK_ISA_LZCNT | OPTION_MASK_ISA_64BIT, CODE_FOR_lzcnt_di,
"__builtin_ia32_lzcnt_u64", IX86_BUILTIN_LZCNT64, UNKNOWN, (int)
UINT64_FTYPE_UINT64 },
@@ -33821,6 +33825,8 @@ static const struct builtin_description bdesc_args
{ OPTION_MASK_ISA_BMI | OPTION_MASK_ISA_64BIT, CODE_FOR_bmi_bextr_di,
"__builtin_ia32_bextr_u64", IX86_BUILTIN_BEXTR64, UNKNOWN, (int)
UINT64_FTYPE_UINT64_UINT64 },
{ OPTION_MASK_ISA_BMI, CODE_FOR_bmi_tzcnt_hi, "__builtin_ia32_tzcnt_u16",
IX86_BUILTIN_TZCNT16, UNKNOWN, (int) UINT16_FTYPE_UINT16 },
+ /* Same as above, for backward compatibility. */
+ { OPTION_MASK_ISA_BMI, CODE_FOR_bmi_tzcnt_hi, "__builtin_ctzs",
IX86_BUILTIN_CTZS, UNKNOWN, (int) UINT16_FTYPE_UINT16 },
{ OPTION_MASK_ISA_BMI, CODE_FOR_bmi_tzcnt_si, "__builtin_ia32_tzcnt_u32",
IX86_BUILTIN_TZCNT32, UNKNOWN, (int) UINT_FTYPE_UINT },
{ OPTION_MASK_ISA_BMI | OPTION_MASK_ISA_64BIT, CODE_FOR_bmi_tzcnt_di,
"__builtin_ia32_tzcnt_u64", IX86_BUILTIN_TZCNT64, UNKNOWN, (int)
UINT64_FTYPE_UINT64 },
@@ -37603,6 +37609,7 @@ ix86_fold_builtin (tree fndecl, int n_args,
return fold_builtin_cpu (fndecl, args);
case IX86_BUILTIN_TZCNT16:
+ case IX86_BUILTIN_CTZS:
case IX86_BUILTIN_TZCNT32:
case IX86_BUILTIN_TZCNT64:
gcc_assert (n_args == 1);
@@ -37610,7 +37617,8 @@ ix86_fold_builtin (tree fndecl, int n_args,
{
tree type = TREE_TYPE (TREE_TYPE (fndecl));
tree arg = args[0];
- if (fn_code == IX86_BUILTIN_TZCNT16)
+ if (fn_code == IX86_BUILTIN_TZCNT16
+ || fn_code == IX86_BUILTIN_CTZS)
arg = fold_convert (short_unsigned_type_node, arg);
if (integer_zerop (arg))
return build_int_cst (type, TYPE_PRECISION (TREE_TYPE (arg)));
@@ -37620,6 +37628,7 @@ ix86_fold_builtin (tree fndecl, int n_args,
break;
case IX86_BUILTIN_LZCNT16:
+ case IX86_BUILTIN_CLZS:
case IX86_BUILTIN_LZCNT32:
case IX86_BUILTIN_LZCNT64:
gcc_assert (n_args == 1);
@@ -37627,7 +37636,8 @@ ix86_fold_builtin (tree fndecl, int n_args,
{
tree type = TREE_TYPE (TREE_TYPE (fndecl));
tree arg = args[0];
- if (fn_code == IX86_BUILTIN_LZCNT16)
+ if (fn_code == IX86_BUILTIN_LZCNT16
+ || fn_code == IX86_BUILTIN_CLZS)
arg = fold_convert (short_unsigned_type_node, arg);
if (integer_zerop (arg))
return build_int_cst (type, TYPE_PRECISION (TREE_TYPE (arg)));
