diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/expr.c | 19 | ||||
| -rw-r--r-- | gcc/simplify-rtx.c | 52 |
2 files changed, 60 insertions, 11 deletions
@@ -688,7 +688,24 @@ convert_modes (machine_mode mode, machine_mode oldmode, rtx x, int unsignedp) && (GET_MODE_PRECISION (subreg_promoted_mode (x)) >= GET_MODE_PRECISION (int_mode)) && SUBREG_CHECK_PROMOTED_SIGN (x, unsignedp)) - x = gen_lowpart (int_mode, SUBREG_REG (x)); + { + scalar_int_mode int_orig_mode; + machine_mode orig_mode = GET_MODE (x); + x = gen_lowpart (int_mode, SUBREG_REG (x)); + + /* Preserve SUBREG_PROMOTED_VAR_P if the new mode is wider than + the original mode, but narrower than the inner mode. */ + if (GET_CODE (x) == SUBREG + && GET_MODE_PRECISION (subreg_promoted_mode (x)) + > GET_MODE_PRECISION (int_mode) + && is_a <scalar_int_mode> (orig_mode, &int_orig_mode) + && GET_MODE_PRECISION (int_mode) + > GET_MODE_PRECISION (int_orig_mode)) + { + SUBREG_PROMOTED_VAR_P (x) = 1; + SUBREG_PROMOTED_SET (x, unsignedp); + } + } if (GET_MODE (x) != VOIDmode) oldmode = GET_MODE (x); diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index e431e0c..ebad5cb 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -1512,12 +1512,28 @@ simplify_context::simplify_unary_operation_1 (rtx_code code, machine_mode mode, target mode is the same as the variable's promotion. */ if (GET_CODE (op) == SUBREG && SUBREG_PROMOTED_VAR_P (op) - && SUBREG_PROMOTED_SIGNED_P (op) - && !paradoxical_subreg_p (mode, GET_MODE (SUBREG_REG (op)))) + && SUBREG_PROMOTED_SIGNED_P (op)) { - temp = rtl_hooks.gen_lowpart_no_emit (mode, SUBREG_REG (op)); - if (temp) - return temp; + rtx subreg = SUBREG_REG (op); + machine_mode subreg_mode = GET_MODE (subreg); + if (!paradoxical_subreg_p (mode, subreg_mode)) + { + temp = rtl_hooks.gen_lowpart_no_emit (mode, subreg); + if (temp) + { + /* Preserve SUBREG_PROMOTED_VAR_P. */ + if (partial_subreg_p (temp)) + { + SUBREG_PROMOTED_VAR_P (temp) = 1; + SUBREG_PROMOTED_SET (temp, 1); + } + return temp; + } + } + else + /* Sign-extending a sign-extended subreg. */ + return simplify_gen_unary (SIGN_EXTEND, mode, + subreg, subreg_mode); } /* (sign_extend:M (sign_extend:N <X>)) is (sign_extend:M <X>). @@ -1631,12 +1647,28 @@ simplify_context::simplify_unary_operation_1 (rtx_code code, machine_mode mode, target mode is the same as the variable's promotion. */ if (GET_CODE (op) == SUBREG && SUBREG_PROMOTED_VAR_P (op) - && SUBREG_PROMOTED_UNSIGNED_P (op) - && !paradoxical_subreg_p (mode, GET_MODE (SUBREG_REG (op)))) + && SUBREG_PROMOTED_UNSIGNED_P (op)) { - temp = rtl_hooks.gen_lowpart_no_emit (mode, SUBREG_REG (op)); - if (temp) - return temp; + rtx subreg = SUBREG_REG (op); + machine_mode subreg_mode = GET_MODE (subreg); + if (!paradoxical_subreg_p (mode, subreg_mode)) + { + temp = rtl_hooks.gen_lowpart_no_emit (mode, subreg); + if (temp) + { + /* Preserve SUBREG_PROMOTED_VAR_P. */ + if (partial_subreg_p (temp)) + { + SUBREG_PROMOTED_VAR_P (temp) = 1; + SUBREG_PROMOTED_SET (temp, 0); + } + return temp; + } + } + else + /* Zero-extending a zero-extended subreg. */ + return simplify_gen_unary (ZERO_EXTEND, mode, + subreg, subreg_mode); } /* Extending a widening multiplication should be canonicalized to |