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| author | Uros Bizjak <uros@gcc.gnu.org> | 2017-05-12 20:52:51 +0200 |
|---|---|---|
| committer | Uros Bizjak <uros@gcc.gnu.org> | 2017-05-12 20:52:51 +0200 |
| commit | 88ce9dc38a0590608dd036e08758b478f8ca429c (patch) | |
| tree | 0fae5c62139cd17defd0553bc7128f24b2c2e1bc /gcc | |
| parent | b76f15500970fd9b00ae4c6979fbe1b4ab7ed126 (diff) | |
| download | gcc-88ce9dc38a0590608dd036e08758b478f8ca429c.zip gcc-88ce9dc38a0590608dd036e08758b478f8ca429c.tar.gz gcc-88ce9dc38a0590608dd036e08758b478f8ca429c.tar.bz2 | |
re PR target/80723 (FAIL gcc.target/i386/cadd.c scan assembler sbb)
PR target/80723
* config/i386/i386.c (ix86_rtx_cost) [case PLUS]: Ignore the
cost of adding a carry flag for ADC instruction.
[case MINUS]: Ignore the cost of subtracting a carry flag
for SBB instruction.
From-SVN: r247991
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 10 | ||||
| -rw-r--r-- | gcc/config/i386/i386.c | 27 |
2 files changed, 33 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 99f1648..cc9f7a3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2017-05-12 Uros Bizjak <ubizjak@gmail.com> + + PR target/80723 + * config/i386/i386.c (ix86_rtx_cost) [case PLUS]: Ignore the + cost of adding a carry flag for ADC instruction. + [case MINUS]: Ignore the cost of subtracting a carry flag + for SBB instruction. + 2017-05-12 Steven Munroe <munroesj@gcc.gnu.org> * config.gcc (powerpc*-*-*): Add bmi2intrin.h, bmiintrin.h, @@ -8,7 +16,7 @@ 2017-05-12 Jeff Law <law@redhat.com> - * tree-vrp.c (vrp_dom_walker::before_dom_childern): Push unwinding + * tree-vrp.c (vrp_dom_walker::before_dom_children): Push unwinding markers. 2017-05-12 Peter Bergner <bergner@vnet.ibm.com> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index 7e8cdb9..b5bdcd6 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -40913,9 +40913,16 @@ ix86_rtx_costs (rtx x, machine_mode mode, int outer_code_i, int opno, } else if (GET_CODE (XEXP (x, 0)) == PLUS) { - *total = cost->lea; - *total += rtx_cost (XEXP (XEXP (x, 0), 0), mode, - outer_code, opno, speed); + /* Add with carry, ignore the cost of adding a carry flag. */ + if (ix86_carry_flag_operator (XEXP (XEXP (x, 0), 0), mode)) + *total = cost->add; + else + { + *total = cost->lea; + *total += rtx_cost (XEXP (XEXP (x, 0), 0), mode, + outer_code, opno, speed); + } + *total += rtx_cost (XEXP (XEXP (x, 0), 1), mode, outer_code, opno, speed); *total += rtx_cost (XEXP (x, 1), mode, @@ -40926,6 +40933,20 @@ ix86_rtx_costs (rtx x, machine_mode mode, int outer_code_i, int opno, /* FALLTHRU */ case MINUS: + /* Subtract with borrow, ignore the cost of subtracting a carry flag. */ + if (GET_MODE_CLASS (mode) == MODE_INT + && GET_MODE_SIZE (mode) <= UNITS_PER_WORD + && GET_CODE (XEXP (x, 0)) == MINUS + && ix86_carry_flag_operator (XEXP (XEXP (x, 0), 1), mode)) + { + *total = cost->add; + *total += rtx_cost (XEXP (XEXP (x, 0), 0), mode, + outer_code, opno, speed); + *total += rtx_cost (XEXP (x, 1), mode, + outer_code, opno, speed); + return true; + } + if (SSE_FLOAT_MODE_P (mode) && TARGET_SSE_MATH) { /* ??? SSE cost should be used here. */ |