| Message ID | a8c9847a4476b2271560398107138ca36bc9f336.1418641560.git.segher@kernel.crashing.org |
|---|---|
| State | New |
| Headers | show |
On Mon, Dec 15, 2014 at 6:11 AM, Segher Boessenkool <segher@kernel.crashing.org> wrote: > If an addic. is split to addi+cmp (because RA didn't give it CR0), it will > do the wrong thing if the input reg is GPR0 ("addi X,0,N" is "li X,N"). > So don't allow such an input. > > Spotted visually while investigating PR64268. Tested etc.; okay for > mainline? > > > Segher > > > 2014-12-15 Segher Boessenkool <segher@kernel.crashing.org> > > gcc/ > * gcc/config/rs6000/rs6000.md (*add>mode>3_imm_dot, > *add<mode>3_imm_dot2): Change the constraint for the second > alternative for operand 1 from "r" to "b". Okay. thanks, David
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md index bb9ab0f..36e6182 100644 --- a/gcc/config/rs6000/rs6000.md +++ b/gcc/config/rs6000/rs6000.md @@ -1569,7 +1569,7 @@ (define_insn_and_split "*add<mode>3_dot2" (define_insn_and_split "*add<mode>3_imm_dot" [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y") - (compare:CC (plus:GPR (match_operand:GPR 1 "gpc_reg_operand" "%r,r") + (compare:CC (plus:GPR (match_operand:GPR 1 "gpc_reg_operand" "%r,b") (match_operand:GPR 2 "short_cint_operand" "I,I")) (const_int 0))) (clobber (match_scratch:GPR 0 "=r,r")) @@ -1592,7 +1592,7 @@ (define_insn_and_split "*add<mode>3_imm_dot" (define_insn_and_split "*add<mode>3_imm_dot2" [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y") - (compare:CC (plus:GPR (match_operand:GPR 1 "gpc_reg_operand" "%r,r") + (compare:CC (plus:GPR (match_operand:GPR 1 "gpc_reg_operand" "%r,b") (match_operand:GPR 2 "short_cint_operand" "I,I")) (const_int 0))) (set (match_operand:GPR 0 "gpc_reg_operand" "=r,r")
If an addic. is split to addi+cmp (because RA didn't give it CR0), it will do the wrong thing if the input reg is GPR0 ("addi X,0,N" is "li X,N"). So don't allow such an input. Spotted visually while investigating PR64268. Tested etc.; okay for mainline? Segher 2014-12-15 Segher Boessenkool <segher@kernel.crashing.org> gcc/ * gcc/config/rs6000/rs6000.md (*add>mode>3_imm_dot, *add<mode>3_imm_dot2): Change the constraint for the second alternative for operand 1 from "r" to "b". --- gcc/config/rs6000/rs6000.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)