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author | H.J. Lu <hjl.tools@gmail.com> | 2022-10-20 11:55:19 -0700 |
---|---|---|
committer | H.J. Lu <hjl.tools@gmail.com> | 2022-10-27 11:41:54 -0700 |
commit | 0e36a9c6915c713d30016cbade97a4b31dcc1350 (patch) | |
tree | 19af9d463981225452ec3a82498371f9a269612b /gcc/config | |
parent | 1c2b53ce8bbf5bbe1ddb13bb6005f432726518ae (diff) | |
download | gcc-0e36a9c6915c713d30016cbade97a4b31dcc1350.zip gcc-0e36a9c6915c713d30016cbade97a4b31dcc1350.tar.gz gcc-0e36a9c6915c713d30016cbade97a4b31dcc1350.tar.bz2 |
x86: Replace ne:CCC/ne:CCO with UNSPEC_CC_NE in neg patterns
In i386.md, neg patterns which set MODE_CC register like
(set (reg:CCC FLAGS_REG)
(ne:CCC (match_operand:SWI48 1 "general_reg_operand") (const_int 0)))
can lead to errors when operand 1 is a constant value. If FLAGS_REG in
(set (reg:CCC FLAGS_REG)
(ne:CCC (const_int 2) (const_int 0)))
is set to 1, RTX simplifiers may simplify
(set (reg:SI 93)
(neg:SI (ltu:SI (reg:CCC 17 flags) (const_int 0 [0]))))
as
(set (reg:SI 93)
(neg:SI (ltu:SI (const_int 1) (const_int 0 [0]))))
which leads to incorrect results since LTU on MODE_CC register isn't the
same as "unsigned less than" in x86 backend. To prevent RTL optimizers
from setting MODE_CC register to a constant, use UNSPEC_CC_NE to replace
ne:CCC/ne:CCO when setting FLAGS_REG in neg patterns.
gcc/
PR target/107172
* config/i386/i386.md (UNSPEC_CC_NE): New.
Replace ne:CCC/ne:CCO with UNSPEC_CC_NE in neg patterns.
gcc/testsuite/
PR target/107172
* gcc.target/i386/pr107172.c: New test.
Diffstat (limited to 'gcc/config')
-rw-r--r-- | gcc/config/i386/i386.md | 45 |
1 files changed, 25 insertions, 20 deletions
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index baf1f1f..aaa678e 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -113,6 +113,7 @@ UNSPEC_PEEPSIB UNSPEC_INSN_FALSE_DEP UNSPEC_SBB + UNSPEC_CC_NE ;; For SSE/MMX support: UNSPEC_FIX_NOTRUNC @@ -11470,7 +11471,7 @@ "&& reload_completed" [(parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_dup 1) (const_int 0))) + (unspec:CCC [(match_dup 1) (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 0) (neg:DWIH (match_dup 1)))]) (parallel [(set (match_dup 2) @@ -11499,7 +11500,8 @@ (match_operand:SWI48 1 "nonimmediate_gr_operand")) (parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_operand:SWI48 2 "general_reg_operand") (const_int 0))) + (unspec:CCC [(match_operand:SWI48 2 "general_reg_operand") + (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 2) (neg:SWI48 (match_dup 2)))]) (parallel [(set (match_dup 0) @@ -11517,7 +11519,7 @@ && !reg_mentioned_p (operands[2], operands[1])" [(parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_dup 2) (const_int 0))) + (unspec:CCC [(match_dup 2) (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 2) (neg:SWI48 (match_dup 2)))]) (parallel [(set (match_dup 0) @@ -11543,7 +11545,8 @@ (clobber (reg:CC FLAGS_REG))]) (parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_operand:SWI48 1 "general_reg_operand") (const_int 0))) + (unspec:CCC [(match_operand:SWI48 1 "general_reg_operand") + (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 1) (neg:SWI48 (match_dup 1)))]) (parallel [(set (match_dup 0) @@ -11559,7 +11562,7 @@ "REGNO (operands[0]) != REGNO (operands[1])" [(parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_dup 1) (const_int 0))) + (unspec:CCC [(match_dup 1) (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 1) (neg:SWI48 (match_dup 1)))]) (parallel [(set (match_dup 0) @@ -11635,9 +11638,9 @@ (define_insn "*neg<mode>_ccc_1" [(set (reg:CCC FLAGS_REG) - (ne:CCC - (match_operand:SWI 1 "nonimmediate_operand" "0") - (const_int 0))) + (unspec:CCC + [(match_operand:SWI 1 "nonimmediate_operand" "0") + (const_int 0)] UNSPEC_CC_NE)) (set (match_operand:SWI 0 "nonimmediate_operand" "=<r>m") (neg:SWI (match_dup 1)))] "" @@ -11647,9 +11650,9 @@ (define_insn "*neg<mode>_ccc_2" [(set (reg:CCC FLAGS_REG) - (ne:CCC - (match_operand:SWI 1 "nonimmediate_operand" "0") - (const_int 0))) + (unspec:CCC + [(match_operand:SWI 1 "nonimmediate_operand" "0") + (const_int 0)] UNSPEC_CC_NE)) (clobber (match_scratch:SWI 0 "=<r>"))] "" "neg{<imodesuffix>}\t%0" @@ -11659,8 +11662,8 @@ (define_expand "x86_neg<mode>_ccc" [(parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_operand:SWI48 1 "register_operand") - (const_int 0))) + (unspec:CCC [(match_operand:SWI48 1 "register_operand") + (const_int 0)] UNSPEC_CC_NE)) (set (match_operand:SWI48 0 "register_operand") (neg:SWI48 (match_dup 1)))])]) @@ -11686,8 +11689,9 @@ ;; Negate with jump on overflow. (define_expand "negv<mode>3" [(parallel [(set (reg:CCO FLAGS_REG) - (ne:CCO (match_operand:SWI 1 "register_operand") - (match_dup 3))) + (unspec:CCO + [(match_operand:SWI 1 "register_operand") + (match_dup 3)] UNSPEC_CC_NE)) (set (match_operand:SWI 0 "register_operand") (neg:SWI (match_dup 1)))]) (set (pc) (if_then_else @@ -11703,8 +11707,9 @@ (define_insn "*negv<mode>3" [(set (reg:CCO FLAGS_REG) - (ne:CCO (match_operand:SWI 1 "nonimmediate_operand" "0") - (match_operand:SWI 2 "const_int_operand"))) + (unspec:CCO [(match_operand:SWI 1 "nonimmediate_operand" "0") + (match_operand:SWI 2 "const_int_operand")] + UNSPEC_CC_NE)) (set (match_operand:SWI 0 "nonimmediate_operand" "=<r>m") (neg:SWI (match_dup 1)))] "ix86_unary_operator_ok (NEG, <MODE>mode, operands) @@ -11770,7 +11775,7 @@ "&& 1" [(parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_dup 1) (const_int 0))) + (unspec:CCC [(match_dup 1) (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 2) (neg:DWIH (match_dup 1)))]) (parallel [(set (match_dup 5) @@ -11814,7 +11819,7 @@ "&& 1" [(parallel [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_dup 1) (const_int 0))) + (unspec:CCC [(match_dup 1) (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 2) (neg:DWIH (match_dup 1)))]) (parallel [(set (match_dup 5) @@ -21456,7 +21461,7 @@ (const_int 0))))] "" [(set (reg:CCC FLAGS_REG) - (ne:CCC (match_dup 1) (const_int 0))) + (unspec:CCC [(match_dup 1) (const_int 0)] UNSPEC_CC_NE)) (set (match_dup 0) (neg:SWI (ltu:SWI (reg:CCC FLAGS_REG) (const_int 0))))]) |