The issue with the bug is the power10 load GPR + cmpi -1/0/1 fusion optimization generates illegal assembler code.
Ultimately the code was dying because the fusion load + compare -1/0/1 patterns did not handle the possibility that the load might be prefixed. The main cause is the constraints for the individual loads in the fusion did not match the machine. In particular, LWA is a ds format instruction when it is unprefixed. The code did not also set the prefixed attribute correctly. This patch rewrites the genfusion.pl script so that it will have more accurate constraints for the LWA and LD instructions (which are DS instructions). The updated genfusion.pl was then run to update fusion.md. Finally, the code for the "prefixed" attribute is modified so that it considers load + compare immediate patterns to be like the normal load insns in checking whether operand[1] is a prefixed instruction. I have tested this patch on a little endian power10 system, on a little endian power9 system, and a big endian power8 system (both -m32 and -m64 tested on BE). There were no regressions, can I check this into the trunk? The same patch applies to the gcc-12 and gcc-11 branches. Can I check this patch into those branches also after a burn-in period? 2023-03-21 Michael Meissner <meiss...@linux.ibm.com> Aaron Sawdey <acsaw...@linux.ibm.com> gcc/ PR target/105325 * gcc/config/rs6000/genfusion.pl (gen_ld_cmpi_p10): Improve generation of the ld and lwa instructions which use the DS encoding instead of D. Use the YZ constraint for these loads. Handle prefixed loads better. Set the sign_extend attribute as appropriate. * gcc/config/rs6000/fusion.md: Regenerate. * gcc/config/rs6000/rs6000.md (prefixed attribute): Add fused_load_cmpi instructions to the list of instructions that might have a prefixed load instruction. gcc/testsuite/ PR target/105325 * g++.target/powerpc/pr105325.C: New test. * gcc.target/powerpc/fusion-p10-ldcmpi.c: Adjust insn counts. --- gcc/config/rs6000/genfusion.pl | 26 ++++++++++++++++--- gcc/config/rs6000/fusion.md | 17 +++++++----- gcc/config/rs6000/rs6000.md | 2 +- gcc/testsuite/g++.target/powerpc/pr105325.C | 24 +++++++++++++++++ .../gcc.target/powerpc/fusion-p10-ldcmpi.c | 4 +-- 5 files changed, 59 insertions(+), 14 deletions(-) create mode 100644 gcc/testsuite/g++.target/powerpc/pr105325.C diff --git a/gcc/config/rs6000/genfusion.pl b/gcc/config/rs6000/genfusion.pl index e4db352e0ce..4f367cadc52 100755 --- a/gcc/config/rs6000/genfusion.pl +++ b/gcc/config/rs6000/genfusion.pl @@ -56,7 +56,7 @@ sub mode_to_ldst_char sub gen_ld_cmpi_p10 { my ($lmode, $ldst, $clobbermode, $result, $cmpl, $echr, $constpred, - $mempred, $ccmode, $np, $extend, $resultmode); + $mempred, $ccmode, $np, $extend, $resultmode, $constraint); LMODE: foreach $lmode ('DI','SI','HI','QI') { $ldst = mode_to_ldst_char($lmode); $clobbermode = $lmode; @@ -71,21 +71,34 @@ sub gen_ld_cmpi_p10 CCMODE: foreach $ccmode ('CC','CCUNS') { $np = "NON_PREFIXED_D"; $mempred = "non_update_memory_operand"; + $constraint = "m"; if ( $ccmode eq 'CC' ) { next CCMODE if $lmode eq 'QI'; - if ( $lmode eq 'DI' || $lmode eq 'SI' ) { + if ( $lmode eq 'HI' ) { + $np = "NON_PREFIXED_D"; + $mempred = "non_update_memory_operand"; + $echr = "a"; + } elsif ( $lmode eq 'SI' ) { + # ld and lwa are both DS-FORM. + $np = "NON_PREFIXED_DS"; + $mempred = "lwa_operand"; + $echr = "a"; + $constraint = "YZ"; + } elsif ( $lmode eq 'DI' ) { # ld and lwa are both DS-FORM. $np = "NON_PREFIXED_DS"; $mempred = "ds_form_mem_operand"; + $echr = ""; + $constraint = "YZ"; } $cmpl = ""; - $echr = "a"; $constpred = "const_m1_to_1_operand"; } else { if ( $lmode eq 'DI' ) { # ld is DS-form, but lwz is not. $np = "NON_PREFIXED_DS"; $mempred = "ds_form_mem_operand"; + $constraint = "YZ"; } $cmpl = "l"; $echr = "z"; @@ -108,7 +121,7 @@ sub gen_ld_cmpi_p10 print "(define_insn_and_split \"*l${ldst}${echr}_cmp${cmpl}di_cr0_${lmode}_${result}_${ccmode}_${extend}\"\n"; print " [(set (match_operand:${ccmode} 2 \"cc_reg_operand\" \"=x\")\n"; - print " (compare:${ccmode} (match_operand:${lmode} 1 \"${mempred}\" \"m\")\n"; + print " (compare:${ccmode} (match_operand:${lmode} 1 \"${mempred}\" \"${constraint}\")\n"; if ($ccmode eq 'CCUNS') { print " "; } print " (match_operand:${lmode} 3 \"${constpred}\" \"n\")))\n"; if ($result eq 'clobber') { @@ -137,6 +150,11 @@ sub gen_ld_cmpi_p10 print " \"\"\n"; print " [(set_attr \"type\" \"fused_load_cmpi\")\n"; print " (set_attr \"cost\" \"8\")\n"; + + if ($extend eq "sign") { + print " (set_attr \"sign_extend\" \"yes\")\n"; + } + print " (set_attr \"length\" \"8\")])\n"; print "\n"; } diff --git a/gcc/config/rs6000/fusion.md b/gcc/config/rs6000/fusion.md index d45fb138a70..da9953d9ad9 100644 --- a/gcc/config/rs6000/fusion.md +++ b/gcc/config/rs6000/fusion.md @@ -22,7 +22,7 @@ ;; load mode is DI result mode is clobber compare mode is CC extend is none (define_insn_and_split "*ld_cmpdi_cr0_DI_clobber_CC_none" [(set (match_operand:CC 2 "cc_reg_operand" "=x") - (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "m") + (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "YZ") (match_operand:DI 3 "const_m1_to_1_operand" "n"))) (clobber (match_scratch:DI 0 "=r"))] "(TARGET_P10_FUSION)" @@ -43,7 +43,7 @@ (define_insn_and_split "*ld_cmpdi_cr0_DI_clobber_CC_none" ;; load mode is DI result mode is clobber compare mode is CCUNS extend is none (define_insn_and_split "*ld_cmpldi_cr0_DI_clobber_CCUNS_none" [(set (match_operand:CCUNS 2 "cc_reg_operand" "=x") - (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "m") + (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "YZ") (match_operand:DI 3 "const_0_to_1_operand" "n"))) (clobber (match_scratch:DI 0 "=r"))] "(TARGET_P10_FUSION)" @@ -64,7 +64,7 @@ (define_insn_and_split "*ld_cmpldi_cr0_DI_clobber_CCUNS_none" ;; load mode is DI result mode is DI compare mode is CC extend is none (define_insn_and_split "*ld_cmpdi_cr0_DI_DI_CC_none" [(set (match_operand:CC 2 "cc_reg_operand" "=x") - (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "m") + (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "YZ") (match_operand:DI 3 "const_m1_to_1_operand" "n"))) (set (match_operand:DI 0 "gpc_reg_operand" "=r") (match_dup 1))] "(TARGET_P10_FUSION)" @@ -85,7 +85,7 @@ (define_insn_and_split "*ld_cmpdi_cr0_DI_DI_CC_none" ;; load mode is DI result mode is DI compare mode is CCUNS extend is none (define_insn_and_split "*ld_cmpldi_cr0_DI_DI_CCUNS_none" [(set (match_operand:CCUNS 2 "cc_reg_operand" "=x") - (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "m") + (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "YZ") (match_operand:DI 3 "const_0_to_1_operand" "n"))) (set (match_operand:DI 0 "gpc_reg_operand" "=r") (match_dup 1))] "(TARGET_P10_FUSION)" @@ -106,7 +106,7 @@ (define_insn_and_split "*ld_cmpldi_cr0_DI_DI_CCUNS_none" ;; load mode is SI result mode is clobber compare mode is CC extend is none (define_insn_and_split "*lwa_cmpdi_cr0_SI_clobber_CC_none" [(set (match_operand:CC 2 "cc_reg_operand" "=x") - (compare:CC (match_operand:SI 1 "ds_form_mem_operand" "m") + (compare:CC (match_operand:SI 1 "lwa_operand" "YZ") (match_operand:SI 3 "const_m1_to_1_operand" "n"))) (clobber (match_scratch:SI 0 "=r"))] "(TARGET_P10_FUSION)" @@ -148,7 +148,7 @@ (define_insn_and_split "*lwz_cmpldi_cr0_SI_clobber_CCUNS_none" ;; load mode is SI result mode is SI compare mode is CC extend is none (define_insn_and_split "*lwa_cmpdi_cr0_SI_SI_CC_none" [(set (match_operand:CC 2 "cc_reg_operand" "=x") - (compare:CC (match_operand:SI 1 "ds_form_mem_operand" "m") + (compare:CC (match_operand:SI 1 "lwa_operand" "YZ") (match_operand:SI 3 "const_m1_to_1_operand" "n"))) (set (match_operand:SI 0 "gpc_reg_operand" "=r") (match_dup 1))] "(TARGET_P10_FUSION)" @@ -190,7 +190,7 @@ (define_insn_and_split "*lwz_cmpldi_cr0_SI_SI_CCUNS_none" ;; load mode is SI result mode is EXTSI compare mode is CC extend is sign (define_insn_and_split "*lwa_cmpdi_cr0_SI_EXTSI_CC_sign" [(set (match_operand:CC 2 "cc_reg_operand" "=x") - (compare:CC (match_operand:SI 1 "ds_form_mem_operand" "m") + (compare:CC (match_operand:SI 1 "lwa_operand" "YZ") (match_operand:SI 3 "const_m1_to_1_operand" "n"))) (set (match_operand:EXTSI 0 "gpc_reg_operand" "=r") (sign_extend:EXTSI (match_dup 1)))] "(TARGET_P10_FUSION)" @@ -205,6 +205,7 @@ (define_insn_and_split "*lwa_cmpdi_cr0_SI_EXTSI_CC_sign" "" [(set_attr "type" "fused_load_cmpi") (set_attr "cost" "8") + (set_attr "sign_extend" "yes") (set_attr "length" "8")]) ;; load-cmpi fusion pattern generated by gen_ld_cmpi_p10 @@ -247,6 +248,7 @@ (define_insn_and_split "*lha_cmpdi_cr0_HI_clobber_CC_sign" "" [(set_attr "type" "fused_load_cmpi") (set_attr "cost" "8") + (set_attr "sign_extend" "yes") (set_attr "length" "8")]) ;; load-cmpi fusion pattern generated by gen_ld_cmpi_p10 @@ -289,6 +291,7 @@ (define_insn_and_split "*lha_cmpdi_cr0_HI_EXTHI_CC_sign" "" [(set_attr "type" "fused_load_cmpi") (set_attr "cost" "8") + (set_attr "sign_extend" "yes") (set_attr "length" "8")]) ;; load-cmpi fusion pattern generated by gen_ld_cmpi_p10 diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md index 81bffb04ceb..0f809c3793f 100644 --- a/gcc/config/rs6000/rs6000.md +++ b/gcc/config/rs6000/rs6000.md @@ -302,7 +302,7 @@ (define_attr "prefixed" "no,yes" (eq_attr "maybe_prefixed" "no")) (const_string "no") - (eq_attr "type" "load,fpload,vecload") + (eq_attr "type" "load,fpload,vecload,vecload,fused_load_cmpi") (if_then_else (match_test "prefixed_load_p (insn)") (const_string "yes") (const_string "no")) diff --git a/gcc/testsuite/g++.target/powerpc/pr105325.C b/gcc/testsuite/g++.target/powerpc/pr105325.C new file mode 100644 index 00000000000..f4ab384daa7 --- /dev/null +++ b/gcc/testsuite/g++.target/powerpc/pr105325.C @@ -0,0 +1,24 @@ +/* { dg-do assemble } */ +/* { dg-require-effective-target lp64 } */ +/* { dg-require-effective-target powerpc_prefixed_addr } */ +/* { dg-options "-O2 -mdejagnu-cpu=power10 -fstack-protector" } */ + +/* Test that power10 fusion does not generate an LWA/CMPDI instruction pair + instead of PLWZ/CMPWI. Ultimately the code was dying because the fusion + load + compare -1/0/1 patterns did not handle the possibility that the load + might be prefixed. */ + +struct Ath__array1D { + int _current; + int getCnt() { return _current; } +}; +struct extMeasure { + int _mapTable[10000]; + Ath__array1D _metRCTable; +}; +void measureRC() { + extMeasure m; + for (; m._metRCTable.getCnt();) + for (;;) + ; +} diff --git a/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c b/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c index 526a026d874..ca7297375a4 100644 --- a/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c +++ b/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c @@ -61,7 +61,7 @@ TEST(int8_t) /* { dg-final { scan-assembler-times "lha_cmpdi_cr0_HI_clobber_CC_sign" 16 { target lp64 } } } */ /* { dg-final { scan-assembler-times "lhz_cmpldi_cr0_HI_clobber_CCUNS_zero" 4 { target lp64 } } } */ /* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_EXTSI_CC_sign" 0 { target lp64 } } } */ -/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 4 { target lp64 } } } */ +/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 8 { target lp64 } } } */ /* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_EXTSI_CCUNS_zero" 0 { target lp64 } } } */ /* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_clobber_CCUNS_none" 2 { target lp64 } } } */ @@ -73,6 +73,6 @@ TEST(int8_t) /* { dg-final { scan-assembler-times "lha_cmpdi_cr0_HI_clobber_CC_sign" 8 { target ilp32 } } } */ /* { dg-final { scan-assembler-times "lhz_cmpldi_cr0_HI_clobber_CCUNS_zero" 2 { target ilp32 } } } */ /* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_EXTSI_CC_sign" 0 { target ilp32 } } } */ -/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 9 { target ilp32 } } } */ +/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 16 { target ilp32 } } } */ /* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_EXTSI_CCUNS_zero" 0 { target ilp32 } } } */ /* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_clobber_CCUNS_none" 6 { target ilp32 } } } */ -- 2.39.2 -- Michael Meissner, IBM PO Box 98, Ayer, Massachusetts, USA, 01432 email: meiss...@linux.ibm.com