From: Pan Li <pan2...@intel.com> For QI/HImode of .SAT_ADD, the operands may be sign-extended and the high bits of Xmode may be all 1 which is not expected. For example as below code.
signed char b[1]; unsigned short c; signed char *d = b; int main() { b[0] = -40; c = ({ (unsigned short)d[0] < 0xFFF6 ? (unsigned short)d[0] : 0xFFF6; }) + 9; __builtin_printf("%d\n", c); } After expanding we have: ;; _6 = .SAT_ADD (_3, 9); (insn 8 7 9 (set (reg:DI 143) (high:DI (symbol_ref:DI ("d") [flags 0x86] <var_decl d>))) (nil)) (insn 9 8 10 (set (reg/f:DI 142) (mem/f/c:DI (lo_sum:DI (reg:DI 143) (symbol_ref:DI ("d") [flags 0x86] <var_decl d>)) [1 d+0 S8 A64])) (nil)) (insn 10 9 11 (set (reg:HI 144 [ _3 ]) (sign_extend:HI (mem:QI (reg/f:DI 142) [0 *d.0_1+0 S1 A8]))) "test.c":7:10 -1 (nil)) The convert from signed char to unsigned short will have sign_extend rtl as above. And finally become the lb insn as below: lb a1,0(a5) // a1 is -40, aka 0xffffffffffffffd8 lui a0,0x1a addi a5,a1,9 slli a5,a5,0x30 srli a5,a5,0x30 // a5 is 65505 sltu a1,a5,a1 // compare 65505 and 0xffffffffffffffd8 => TRUE The sltu try to compare 65505 and 0xffffffffffffffd8 here, but we actually want to compare 65505 and 65496 (0xffd8). Thus we need to clean up the high bits to ensure this. The below test suites are passed for this patch: * The rv64gcv fully regression test. PR target/116278 gcc/ChangeLog: * config/riscv/riscv.cc (riscv_gen_zero_extend_rtx): Add new func impl to zero extend rtx. (riscv_expand_usadd): Leverage above func to cleanup operands and sum. gcc/testsuite/ChangeLog: * gcc.target/riscv/pr116278-run-1.c: New test. * gcc.target/riscv/pr116278-run-2.c: New test. PR 116278 gcc/ChangeLog: * config/riscv/riscv.cc (riscv_gen_zero_extend_rtx): Add new func impl to zero extend rtx. (riscv_expand_usadd): Leverage above func to cleanup operands 0 and remove the special handing for SImode in RV64. gcc/testsuite/ChangeLog: * gcc.target/riscv/sat_u_add-11.c: Adjust asm check body. * gcc.target/riscv/sat_u_add-15.c: Ditto. * gcc.target/riscv/sat_u_add-19.c: Ditto. * gcc.target/riscv/sat_u_add-23.c: Ditto. * gcc.target/riscv/sat_u_add-3.c: Ditto. * gcc.target/riscv/sat_u_add-7.c: Ditto. * gcc.target/riscv/sat_u_add_imm-11.c: Ditto. * gcc.target/riscv/sat_u_add_imm-15.c: Ditto. * gcc.target/riscv/sat_u_add_imm-3.c: Ditto. * gcc.target/riscv/sat_u_add_imm-7.c: Ditto. * gcc.target/riscv/pr116278-run-1.c: New test. * gcc.target/riscv/pr116278-run-2.c: New test. Signed-off-by: Pan Li <pan2...@intel.com> --- gcc/config/riscv/riscv.cc | 34 ++++++++++++------- .../gcc.target/riscv/pr116278-run-1.c | 20 +++++++++++ .../gcc.target/riscv/pr116278-run-2.c | 20 +++++++++++ gcc/testsuite/gcc.target/riscv/sat_u_add-11.c | 6 +++- gcc/testsuite/gcc.target/riscv/sat_u_add-15.c | 6 +++- gcc/testsuite/gcc.target/riscv/sat_u_add-19.c | 6 +++- gcc/testsuite/gcc.target/riscv/sat_u_add-23.c | 6 +++- gcc/testsuite/gcc.target/riscv/sat_u_add-3.c | 6 +++- gcc/testsuite/gcc.target/riscv/sat_u_add-7.c | 6 +++- .../gcc.target/riscv/sat_u_add_imm-11.c | 6 +++- .../gcc.target/riscv/sat_u_add_imm-15.c | 6 +++- .../gcc.target/riscv/sat_u_add_imm-3.c | 6 +++- .../gcc.target/riscv/sat_u_add_imm-7.c | 6 +++- 13 files changed, 112 insertions(+), 22 deletions(-) create mode 100644 gcc/testsuite/gcc.target/riscv/pr116278-run-1.c create mode 100644 gcc/testsuite/gcc.target/riscv/pr116278-run-2.c diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc index 1f60d8f9711..453a061428e 100644 --- a/gcc/config/riscv/riscv.cc +++ b/gcc/config/riscv/riscv.cc @@ -11801,12 +11801,29 @@ riscv_get_raw_result_mode (int regno) return default_get_reg_raw_mode (regno); } +/* Generate a new rtx of Xmode based on the rtx and mode in define pattern. + The rtx x will be zero extended to Xmode if the mode is HI/QImode, and + the new zero extended Xmode rtx will be returned. + Or the gen_lowpart rtx of Xmode will be returned. */ + +static rtx +riscv_gen_zero_extend_rtx (rtx x, machine_mode mode) +{ + if (mode == Xmode) + return x; + + rtx xmode_reg = gen_reg_rtx (Xmode); + riscv_emit_unary (ZERO_EXTEND, xmode_reg, x); + + return xmode_reg; +} + /* Implements the unsigned saturation add standard name usadd for int mode. z = SAT_ADD(x, y). => 1. sum = x + y. - 2. sum = truncate (sum) for QI and HI only. + 2. sum = truncate (sum) for non-Xmode. 3. lt = sum < x. 4. lt = -lt. 5. z = sum | lt. */ @@ -11817,22 +11834,15 @@ riscv_expand_usadd (rtx dest, rtx x, rtx y) machine_mode mode = GET_MODE (dest); rtx xmode_sum = gen_reg_rtx (Xmode); rtx xmode_lt = gen_reg_rtx (Xmode); - rtx xmode_x = gen_lowpart (Xmode, x); + rtx xmode_x = riscv_gen_zero_extend_rtx (x, mode); rtx xmode_y = gen_lowpart (Xmode, y); rtx xmode_dest = gen_reg_rtx (Xmode); /* Step-1: sum = x + y */ - if (mode == SImode && mode != Xmode) - { /* Take addw to avoid the sum truncate. */ - rtx simode_sum = gen_reg_rtx (SImode); - riscv_emit_binary (PLUS, simode_sum, x, y); - emit_move_insn (xmode_sum, gen_lowpart (Xmode, simode_sum)); - } - else - riscv_emit_binary (PLUS, xmode_sum, xmode_x, xmode_y); + riscv_emit_binary (PLUS, xmode_sum, xmode_x, xmode_y); - /* Step-1.1: truncate sum for HI and QI as we have no insn for add QI/HI. */ - if (mode == HImode || mode == QImode) + /* Step-1.1: truncate sum for non-Xmode for overflow check. */ + if (mode != Xmode) { int shift_bits = GET_MODE_BITSIZE (Xmode) - GET_MODE_BITSIZE (mode).to_constant (); diff --git a/gcc/testsuite/gcc.target/riscv/pr116278-run-1.c b/gcc/testsuite/gcc.target/riscv/pr116278-run-1.c new file mode 100644 index 00000000000..d3812bdcdfb --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/pr116278-run-1.c @@ -0,0 +1,20 @@ +/* { dg-do run { target { riscv_v } } } */ +/* { dg-options "-O2 -fdump-rtl-expand-details" } */ + +#include <stdint-gcc.h> + +int8_t b[1]; +int8_t *d = b; +int32_t c; + +int main() { + b[0] = -40; + uint16_t t = (uint16_t)d[0]; + + c = (t < 0xFFF6 ? t : 0xFFF6) + 9; + + if (c != 65505) + __builtin_abort (); +} + +/* { dg-final { scan-rtl-dump-times ".SAT_ADD " 2 "expand" } } */ diff --git a/gcc/testsuite/gcc.target/riscv/pr116278-run-2.c b/gcc/testsuite/gcc.target/riscv/pr116278-run-2.c new file mode 100644 index 00000000000..669cd4f003f --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/pr116278-run-2.c @@ -0,0 +1,20 @@ +/* { dg-do run { target { riscv_v } } } */ +/* { dg-options "-O2 -fdump-rtl-expand-details" } */ + +#include <stdint-gcc.h> + +int16_t b[1]; +int16_t *d = b; +int64_t c; + +int main() { + b[0] = -40; + uint32_t t = (uint32_t)d[0]; + + c = (t < 0xFFFFFFF6u ? t : 0xFFFFFFF6u) + 9; + + if (c != 4294967265) + __builtin_abort (); +} + +/* { dg-final { scan-rtl-dump-times ".SAT_ADD " 2 "expand" } } */ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add-11.c b/gcc/testsuite/gcc.target/riscv/sat_u_add-11.c index b6dc779b212..e248aeafa8e 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add-11.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add-11.c @@ -6,7 +6,11 @@ /* ** sat_u_add_uint32_t_fmt_3: -** addw\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** add\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add-15.c b/gcc/testsuite/gcc.target/riscv/sat_u_add-15.c index 27de543159d..bb8b991a84e 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add-15.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add-15.c @@ -6,7 +6,11 @@ /* ** sat_u_add_uint32_t_fmt_4: -** addw\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** add\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add-19.c b/gcc/testsuite/gcc.target/riscv/sat_u_add-19.c index 491909165dc..7e4ae12f2f5 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add-19.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add-19.c @@ -6,7 +6,11 @@ /* ** sat_u_add_uint32_t_fmt_5: -** addw\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** add\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add-23.c b/gcc/testsuite/gcc.target/riscv/sat_u_add-23.c index 3b82bdffb59..49bbb74a401 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add-23.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add-23.c @@ -6,7 +6,11 @@ /* ** sat_u_add_uint32_t_fmt_6: -** addw\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** add\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add-3.c b/gcc/testsuite/gcc.target/riscv/sat_u_add-3.c index 12347c607bd..cd15dc96450 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add-3.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add-3.c @@ -6,7 +6,11 @@ /* ** sat_u_add_uint32_t_fmt_1: -** addw\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** add\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add-7.c b/gcc/testsuite/gcc.target/riscv/sat_u_add-7.c index fe9dcd4f806..a0b79b15ac4 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add-7.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add-7.c @@ -6,7 +6,11 @@ /* ** sat_u_add_uint32_t_fmt_2: -** addw\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** add\s+[atx][0-9]+,\s*a0,\s*a1 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-11.c b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-11.c index f30e2405a0d..43f34b5f3c9 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-11.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-11.c @@ -6,7 +6,11 @@ /* ** sat_u_add_imm7_uint32_t_fmt_3: -** addiw\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** addi\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-15.c b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-15.c index 3918d215658..eeea574bba2 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-15.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-15.c @@ -6,7 +6,11 @@ /* ** sat_u_add_imm7_uint32_t_fmt_4: -** addiw\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** addi\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-3.c b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-3.c index 21cc903c78e..6283168b46d 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-3.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-3.c @@ -6,7 +6,11 @@ /* ** sat_u_add_imm7_uint32_t_fmt_1: -** addiw\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** addi\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ diff --git a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-7.c b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-7.c index 044b821f7b5..9008d2f946a 100644 --- a/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-7.c +++ b/gcc/testsuite/gcc.target/riscv/sat_u_add_imm-7.c @@ -6,7 +6,11 @@ /* ** sat_u_add_imm7_uint32_t_fmt_2: -** addiw\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*a0,\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 +** addi\s+[atx][0-9]+,\s*a0,\s*7 +** slli\s+[atx][0-9]+,\s*[atx][0-9],\s*32 +** srli\s+[atx][0-9]+,\s*[atx][0-9]+,\s*32 ** sltu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ ** neg\s+[atx][0-9]+,\s*[atx][0-9]+ ** or\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+ -- 2.43.0