Hi, this patch changes the default from always enabling movmisalign to disabling it. It adds an option to override the default and adds generic-ooo to the uarchs that support misaligned vector access.
It also adds a check_effective_target_riscv_v_misalign_ok to the testsuite which enables or disables the vector misalignment tests depending on whether the target under test can execute a misaligned vle32. I haven't actually tested it on a target that does not support misaligned vector loads, though. Regtested on rv64gcv_zvfh_zvbb. There are a few additional failures in the rvv testsuite. They are caused by us overwriting the default vectorizer flags rather than appending. I'm going to fix them in a subsequent patch but for now I'd rather get things rolling. Regards Robin gcc/ChangeLog: * config/riscv/riscv-opts.h (TARGET_VECTOR_MISALIGN_SUPPORTED): Move from here... * config/riscv/riscv.h (TARGET_VECTOR_MISALIGN_SUPPORTED): ...to here and make dependent on uarch and rvv_allow_misalign. * config/riscv/riscv.opt: Add -mrvv-allow-unaligned. gcc/testsuite/ChangeLog: * lib/target-supports.exp: Add check_effective_target_riscv_v_misalign_ok. --- gcc/config/riscv/riscv-opts.h | 3 --- gcc/config/riscv/riscv.h | 5 ++++ gcc/config/riscv/riscv.opt | 5 ++++ gcc/testsuite/lib/target-supports.exp | 34 +++++++++++++++++++++++++-- 4 files changed, 42 insertions(+), 5 deletions(-) diff --git a/gcc/config/riscv/riscv-opts.h b/gcc/config/riscv/riscv-opts.h index 1b2dd5757a8..f58a07abffc 100644 --- a/gcc/config/riscv/riscv-opts.h +++ b/gcc/config/riscv/riscv-opts.h @@ -147,9 +147,6 @@ enum rvv_vector_bits_enum { ? 0 \ : 32 << (__builtin_popcount (opts->x_riscv_zvl_flags) - 1)) -/* TODO: Enable RVV movmisalign by default for now. */ -#define TARGET_VECTOR_MISALIGN_SUPPORTED 1 - /* The maximmum LMUL according to user configuration. */ #define TARGET_MAX_LMUL \ (int) (rvv_max_lmul == RVV_DYNAMIC ? RVV_M8 : rvv_max_lmul) diff --git a/gcc/config/riscv/riscv.h b/gcc/config/riscv/riscv.h index d6b14c4d620..8434e5677b6 100644 --- a/gcc/config/riscv/riscv.h +++ b/gcc/config/riscv/riscv.h @@ -934,6 +934,11 @@ extern enum riscv_cc get_riscv_cc (const rtx use); || (riscv_microarchitecture == sifive_p400) \ || (riscv_microarchitecture == sifive_p600)) +/* True if the target supports misaligned vector loads and stores. */ +#define TARGET_VECTOR_MISALIGN_SUPPORTED \ + (rvv_allow_misalign == 1 \ + || riscv_microarchitecture == generic_ooo) + #define LOGICAL_OP_NON_SHORT_CIRCUIT 0 /* Control the assembler format that we output. */ diff --git a/gcc/config/riscv/riscv.opt b/gcc/config/riscv/riscv.opt index 87f58332016..cff34eee8c9 100644 --- a/gcc/config/riscv/riscv.opt +++ b/gcc/config/riscv/riscv.opt @@ -628,3 +628,8 @@ Specify TLS dialect. mfence-tso Target Var(TARGET_FENCE_TSO) Init(1) Specifies whether the fence.tso instruction should be used. + +mrvv-allow-misalign +Target Var(rvv_allow_misalign) Init(0) +Allow the creation of misaligned vector loads and stores irrespective of the +current uarch. The default is off. diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp index f0f6da52275..ebb908f5c8f 100644 --- a/gcc/testsuite/lib/target-supports.exp +++ b/gcc/testsuite/lib/target-supports.exp @@ -2034,7 +2034,7 @@ proc check_effective_target_riscv_zvfh_ok { } { # check if we can execute vector insns with the given hardware or # simulator set gcc_march [regsub {[[:alnum:]]*} [riscv_get_arch] &v] - if { [check_runtime ${gcc_march}_exec { + if { [check_runtime ${gcc_march}_zvfh_exec { int main() { asm ("vsetivli zero,8,e16,m1,ta,ma"); @@ -2047,6 +2047,29 @@ proc check_effective_target_riscv_zvfh_ok { } { return 0 } +# Return 1 if we can load a vector from a 1-byte aligned address. + +proc check_effective_target_riscv_v_misalign_ok { } { + + if { ![check_effective_target_riscv_v_ok] } { + return 0 + } + + set gcc_march [riscv_get_arch] + if { [check_runtime ${gcc_march}_misalign_exec { + int main() { + unsigned char a[16] + = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}; + asm ("vsetivli zero,7,e8,m1,ta,ma"); + asm ("addi a7,%0,1" : : "r" (a) : "a7" ); + asm ("vle8.v v8,0(a7)" : : : "v8"); + return 0; } } "-march=${gcc_march}"] } { + return 1 + } + + return 0 +} + proc riscv_get_arch { } { set gcc_march "" # ??? do we neeed to add more extensions to the list below? @@ -8139,7 +8162,6 @@ proc check_effective_target_vect_hw_misalign { } { || ([istarget mips*-*-*] && [et-is-effective-target mips_msa]) || ([istarget s390*-*-*] && [check_effective_target_s390_vx]) - || ([istarget riscv*-*-*]) || ([istarget loongarch*-*-*]) || [istarget amdgcn*-*-*] } { return 1 @@ -8148,6 +8170,11 @@ proc check_effective_target_vect_hw_misalign { } { && ![check_effective_target_arm_vect_no_misalign] } { return 1 } + if { [istarget riscv*-*-*] + && [check_effective_target_riscv_v_misalign_ok] } { + return 1 + } + return 0 }] } @@ -11565,6 +11592,9 @@ proc check_vect_support_and_set_flags { } { } elseif [istarget riscv*-*-*] { if [check_effective_target_riscv_v] { set dg-do-what-default run + if [check_effective_target_riscv_v_misalign_ok] { + lappend DEFAULT_VECTCFLAGS "-mrvv-allow-misalign" + } } else { foreach item [add_options_for_riscv_v ""] { lappend DEFAULT_VECTCFLAGS $item -- 2.45.0