Thanks for taking care of this issue. Ok to backport GCC-13. juzhe.zhong@rivai.ai From: Li Xu Date: 2023-08-28 10:33 To: xuli1; gcc-patches CC: kito.cheng; palmer; juzhe.zhong Subject: Re: [PATCH V2] RISC-V: Insert vsetivli zero, 0 for vmv.x.s/vfmv.f.s instructions satisfying REG_P(operand[1]) in -O0. This patch should be backported to releases/gcc-13 to address https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111076 -------------- Li Xu >This issue happens is because the operand1 of scalar move can be >REG_P (operand[1]) in the O0 case, which causes the VSETVL PASS to >not insert the vsetvl instruction correctly, and the compiler crashes. > >Consider this following case: >int16_t foo1 (void *base, size_t vl) >{ > int16_t maxVal = __riscv_vmv_x_s_i16m1_i16 (__riscv_vle16_v_i16m1 (base, vl)); > return maxVal; >} > >Before this patch: >bug.c:15:1: internal compiler error: Segmentation fault > 15 | } > | ^ >0x145d723 crash_signal > ../.././riscv-gcc/gcc/toplev.cc:314 >0x22929dd const_csr_operand(rtx_def*, machine_mode) > ../.././riscv-gcc/gcc/config/riscv/predicates.md:44 >0x2292a21 csr_operand(rtx_def*, machine_mode) > ../.././riscv-gcc/gcc/config/riscv/predicates.md:46 >0x23dfbb0 recog_356 > ../.././riscv-gcc/gcc/config/riscv/iterators.md:72 >0x23efecd recog(rtx_def*, rtx_insn*, int*) > ../.././riscv-gcc/gcc/config/riscv/iterators.md:89 >0xdddc15 recog_memoized(rtx_insn*) > ../.././riscv-gcc/gcc/recog.h:273 > >After this patch: > vsetivli zero,0,e16,m1,ta,ma > vmv.x.s a5,v1 > >gcc/ChangeLog: > > * config/riscv/riscv-vsetvl.cc (gen_vsetvl_pat): For vfmv.f.s/vmv.x.s intruction replace null avl with (const_int 0). > >gcc/testsuite/ChangeLog: > > * gcc.target/riscv/rvv/base/scalar_move-10.c: New test. > * gcc.target/riscv/rvv/base/scalar_move-11.c: New test. >--- > gcc/config/riscv/riscv-vsetvl.cc | 5 +++ > .../riscv/rvv/base/scalar_move-10.c | 31 +++++++++++++++++++ > .../riscv/rvv/base/scalar_move-11.c | 20 ++++++++++++ > 3 files changed, 56 insertions(+) > create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-10.c > create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-11.c > >diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc >index d4d6f336ef9..14ebae1f3f6 100644 >--- a/gcc/config/riscv/riscv-vsetvl.cc >+++ b/gcc/config/riscv/riscv-vsetvl.cc >@@ -618,6 +618,11 @@ static rtx > gen_vsetvl_pat (enum vsetvl_type insn_type, const vl_vtype_info &info, rtx vl) > { > rtx avl = info.get_avl (); >+ /* if optimization == 0 and the instruction is vmv.x.s/vfmv.f.s, >+ set the value of avl to (const_int 0) so that VSETVL PASS will >+ insert vsetvl correctly.*/ >+ if (info.has_avl_no_reg ()) >+ avl = GEN_INT (0); > rtx sew = gen_int_mode (info.get_sew (), Pmode); > rtx vlmul = gen_int_mode (info.get_vlmul (), Pmode); > rtx ta = gen_int_mode (info.get_ta (), Pmode); >diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-10.c b/gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-10.c >new file mode 100644 >index 00000000000..9760d77fb22 >--- /dev/null >+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-10.c >@@ -0,0 +1,31 @@ >+/* { dg-do compile } */ >+/* { dg-options "-march=rv64gcv -mabi=lp64d -O0" } */ >+/* { dg-final { check-function-bodies "**" "" } } */ >+ >+#include "riscv_vector.h" >+ >+/* >+** foo1: >+** ... >+** vsetivli\tzero,0,e16,m1,t[au],m[au] >+** vmv.x.s\t[a-x0-9]+,v[0-9]+ >+** ... >+*/ >+int16_t foo1 (void *base, size_t vl) >+{ >+ int16_t maxVal = __riscv_vmv_x_s_i16m1_i16 (__riscv_vle16_v_i16m1 (base, vl)); >+ return maxVal; >+} >+ >+/* >+** foo2: >+** ... >+** vsetivli\tzero,0,e32,m1,t[au],m[au] >+** vfmv.f.s\tf[a-x0-9]+,v[0-9]+ >+** ... >+*/ >+float foo2 (void *base, size_t vl) >+{ >+ float maxVal = __riscv_vfmv_f_s_f32m1_f32 (__riscv_vle32_v_f32m1 (base, vl)); >+ return maxVal; >+} >diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-11.c b/gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-11.c >new file mode 100644 >index 00000000000..8036acd0a52 >--- /dev/null >+++ b/gcc/testsuite/gcc.target/riscv/rvv/base/scalar_move-11.c >@@ -0,0 +1,20 @@ >+/* { dg-do compile } */ >+/* { dg-options "-march=rv32gcv -mabi=ilp32d -O0" } */ >+/* { dg-final { check-function-bodies "**" "" } } */ >+ >+#include "riscv_vector.h" >+ >+/* >+** foo: >+** ... >+** vsetivli\tzero,0,e64,m4,t[au],m[au] >+** vmv.x.s\t[a-x0-9]+,v[0-9]+ >+** vsetivli\tzero,0,e64,m4,t[au],m[au] >+** vmv.x.s\t[a-x0-9]+,v[0-9]+ >+** ... >+*/ >+int16_t foo (void *base, size_t vl) >+{ >+ int16_t maxVal = __riscv_vmv_x_s_i64m4_i64 (__riscv_vle64_v_i64m4 (base, vl)); >+ return maxVal; >+} >-- >2.17.1