From: Maciej W. Rozycki Date: Sat, 5 Dec 2020 18:26:26 +0000 (+0000) Subject: VAX: Remove EXTV/EXTZV/INSV instruction use from aligned case insns X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=8a8de7507e1cfa2e7a16940a1ad93eb339258042;p=gcc.git VAX: Remove EXTV/EXTZV/INSV instruction use from aligned case insns The INSV machine instruction is the only computational operation in the VAX ISA that keeps condition codes intact. In preparation to MODE_CC transition keep patterns apart then that make or do not make use of said instruction. For consistency update EXTV and EXTZV instruction uses accordingly. In expand SUBREGs will be presented as operands, so handle that possibility in the insn condition. This actually yields better code by avoiding EXTV/EXTZV instructions in pseudo-aligned register cases previously resorting to those instructions: @@ -42,7 +42,7 @@ ins8: subl2 $4,%sp # 21 [c=32] addsi3 movl 4(%ap),%r0 # 2 [c=16] movsi_2 movl 8(%ap),%r1 # 17 [c=16] movsi_2 - insv %r1,$8,$8,%r0 # 9 [c=4] *insv_aligned + insv %r1,$8,$8,%r0 # 9 [c=4] *insv_2 ret # 25 [c=0] return .size ins8, .-ins8 .align 1 @@ -60,12 +60,12 @@ ext8: .globl extz8 .type extz8, @function extz8: - .word 0 # 19 [c=0] procedure_entry_mask - subl2 $4,%sp # 20 [c=32] addsi3 + .word 0 # 18 [c=0] procedure_entry_mask + subl2 $4,%sp # 19 [c=32] addsi3 movl 4(%ap),%r0 # 2 [c=16] movsi_2 - extzv $8,$8,%r0,%r1 # 13 [c=60] *extzv_aligned - movl %r1,%r0 # 18 [c=4] movsi_2 - ret # 24 [c=0] return + rotl $24,%r0,%r0 # 13 [c=60] *extzv_non_const + movzbl %r0,%r0 + ret # 23 [c=0] return .size extz8, .-extz8 .align 1 .globl ins16 @@ -75,7 +75,7 @@ ins16: subl2 $4,%sp # 21 [c=32] addsi3 movl 4(%ap),%r0 # 2 [c=16] movsi_2 movl 8(%ap),%r1 # 17 [c=16] movsi_2 - insv %r1,$16,$16,%r0 # 9 [c=4] *insv_aligned + insv %r1,$16,$16,%r0 # 9 [c=4] *insv_2 ret # 25 [c=0] return .size ins16, .-ins16 .align 1 @@ -94,8 +94,9 @@ ext16: extz16: .word 0 # 18 [c=0] procedure_entry_mask subl2 $4,%sp # 19 [c=32] addsi3 - movl 4(%ap),%r1 # 2 [c=16] movsi_2 - extzv $16,$16,%r1,%r0 # 7 [c=60] *extzv_aligned + movl 4(%ap),%r0 # 2 [c=16] movsi_2 + rotl $16,%r0,%r0 # 7 [c=60] *extzv_non_const + movzwl %r0,%r0 movzwl %r0,%r0 # 13 [c=4] zero_extendhisi2 ret # 23 [c=0] return .size extz16, .-extz16 demonstrated with this program: typedef struct { int f0:1; int f1:7; int f8:8; int f16:16; } bit_t; typedef struct { unsigned int f0:1; unsigned int f1:7; unsigned int f8:8; unsigned int f16:16; } ubit_t; typedef union { bit_t b; int i; } bit_u; typedef union { ubit_t b; unsigned int i; } ubit_u; int ins1 (bit_u x, int y) { asm volatile ("" : "+r" (x), "+r" (y)); x.b.f1 = y; return x.i; } int ext1 (bit_u x) { asm volatile ("" : "+r" (x)); return x.b.f1; } unsigned int extz1 (ubit_u x) { asm volatile ("" : "+r" (x)); return x.b.f1; } int ins8 (bit_u x, int y) { asm volatile ("" : "+r" (x), "+r" (y)); x.b.f8 = y; return x.i; } int ext8 (bit_u x) { asm volatile ("" : "+r" (x)); return x.b.f8; } unsigned int extz8 (ubit_u x) { asm volatile ("" : "+r" (x)); return x.b.f8; } int ins16 (bit_u x, int y) { asm volatile ("" : "+r" (x), "+r" (y)); x.b.f16 = y; return x.i; } int ext16 (bit_u x) { asm volatile ("" : "+r" (x)); return x.b.f16; } unsigned int extz16 (ubit_u x) { asm volatile ("" : "+r" (x)); return x.b.f16; } It also papers over a regression: FAIL: gcc.dg/pr83623.c (internal compiler error) FAIL: gcc.dg/pr83623.c (test for excess errors) from an ICE like: during RTL pass: final .../gcc/testsuite/gcc.dg/pr83623.c: In function 'foo': .../gcc/testsuite/gcc.dg/pr83623.c:13:1: internal compiler error: in change_address_1, at emit-rtl.c:2275 0x10a056e3 change_address_1 .../gcc/emit-rtl.c:2275 0x10a0645f adjust_address_1(rtx_def*, machine_mode, poly_int<1u, long>, int, int, int, poly_int<1u, long>) .../gcc/emit-rtl.c:2409 0x11cb588f output_97 .../gcc/config/vax/vax.md:808 0x10aafb2f get_insn_template(int, rtx_insn*) .../gcc/final.c:2070 0x10ab2b3f final_scan_insn_1 .../gcc/final.c:3039 0x10ab313b final_scan_insn(rtx_insn*, _IO_FILE*, int, int, int*) .../gcc/final.c:3152 0x10aaf887 final_1 .../gcc/final.c:2020 0x10ab703b rest_of_handle_final .../gcc/final.c:4658 0x10ab757b execute .../gcc/final.c:4736 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See for instructions. compiler exited with status 1 FAIL: gcc.dg/pr83623.c (internal compiler error) triggered by an RTL instruction like: (insn 17 14 145 (set (reg:SI 1 %r1) (zero_extract:SI (mem/c:SI (symbol_ref:SI ("x") ) [1 x+0 S4 A128]) (const_int 16 [0x10]) (const_int 16 [0x10]))) ".../gcc/testsuite/gcc.dg/pr83623.c":12:9 97 {*extzv_aligned} (nil)) (where the address cannot be adjusted by 2 for PIC code as requested here as it would create an offset external symbol reference) otherwise caused by the patterns modified here, addressed next. This indicates a further rework is warranted here, but at least problems at hand have been fixed. gcc/ * config/vax/vax.md (*insv_aligned, *extzv_aligned) (*extv_aligned): Reject register bit-field locations that are not aligned to the least significant bit; update output statement accordingly. --- diff --git a/gcc/config/vax/vax.md b/gcc/config/vax/vax.md index de90848a600..80f09d97727 100644 --- a/gcc/config/vax/vax.md +++ b/gcc/config/vax/vax.md @@ -754,8 +754,8 @@ ;; Special cases of bit-field insns which we should ;; recognize in preference to the general case. -;; These handle aligned 8-bit and 16-bit fields, -;; which can usually be done with move instructions. +;; These handle aligned 8-bit and 16-bit fields +;; that can be done with move or convert instructions. (define_insn "*insv_aligned" [(set (zero_extract:SI (match_operand:SI 0 "nonimmediate_operand" "+ro") @@ -766,19 +766,19 @@ && INTVAL (operands[2]) % INTVAL (operands[1]) == 0 && (!MEM_P (operands[0]) || ! mode_dependent_address_p (XEXP (operands[0], 0), - MEM_ADDR_SPACE (operands[0])))" + MEM_ADDR_SPACE (operands[0]))) + && (!(REG_P (operands[0]) + || (SUBREG_P (operands[0]) && REG_P (SUBREG_REG (operands[0])))) + || INTVAL (operands[2]) == 0)" "* { - if (REG_P (operands[0])) - { - if (INTVAL (operands[2]) != 0) - return \"insv %3,%2,%1,%0\"; - } - else + if (!REG_P (operands[0])) operands[0] = adjust_address (operands[0], INTVAL (operands[1]) == 8 ? QImode : HImode, INTVAL (operands[2]) / 8); + else + gcc_assert (INTVAL (operands[2]) == 0); CC_STATUS_INIT; if (INTVAL (operands[1]) == 8) @@ -795,19 +795,19 @@ && INTVAL (operands[3]) % INTVAL (operands[2]) == 0 && (!MEM_P (operands[1]) || ! mode_dependent_address_p (XEXP (operands[1], 0), - MEM_ADDR_SPACE (operands[1])))" + MEM_ADDR_SPACE (operands[1]))) + && (!(REG_P (operands[1]) + || (SUBREG_P (operands[1]) && REG_P (SUBREG_REG (operands[1])))) + || INTVAL (operands[3]) == 0)" "* { - if (REG_P (operands[1])) - { - if (INTVAL (operands[3]) != 0) - return \"extzv %3,%2,%1,%0\"; - } - else + if (!REG_P (operands[1])) operands[1] = adjust_address (operands[1], INTVAL (operands[2]) == 8 ? QImode : HImode, INTVAL (operands[3]) / 8); + else + gcc_assert (INTVAL (operands[3]) == 0); if (INTVAL (operands[2]) == 8) return \"movzbl %1,%0\"; @@ -823,19 +823,19 @@ && INTVAL (operands[3]) % INTVAL (operands[2]) == 0 && (!MEM_P (operands[1]) || ! mode_dependent_address_p (XEXP (operands[1], 0), - MEM_ADDR_SPACE (operands[1])))" + MEM_ADDR_SPACE (operands[1]))) + && (!(REG_P (operands[1]) + || (SUBREG_P (operands[1]) && REG_P (SUBREG_REG (operands[1])))) + || INTVAL (operands[3]) == 0)" "* { - if (REG_P (operands[1])) - { - if (INTVAL (operands[3]) != 0) - return \"extv %3,%2,%1,%0\"; - } - else + if (!REG_P (operands[1])) operands[1] = adjust_address (operands[1], INTVAL (operands[2]) == 8 ? QImode : HImode, INTVAL (operands[3]) / 8); + else + gcc_assert (INTVAL (operands[3]) == 0); if (INTVAL (operands[2]) == 8) return \"cvtbl %1,%0\";