[RISCV] Use the 'B' extension in RISC-V profile definitions #113942
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The specification was recently ratified <https://github.com/riscv/riscv-profiles/blob/main/src/rvb23-profile.adoc>.
RVA22 has retrospectively been defined as including 'B' (as it's a
shorthand for Zba+Zbb+Zbs, which were previously explicitly enumerated)
and RV{A,B,M}23 are defined featuring B. We don't currently infer B
whenever Zba+Zbb+Zbs are present due to concerns about compatibility
with external assemblers such as gas.
llvmbot
added
clang
|
@llvm/pr-subscribers-backend-risc-v @llvm/pr-subscribers-clang-driver Author: Alex Bradbury (asb) ChangesStacks on top of #113918. RVA22 has retroactively been defined as including 'B' (as it's a Marked as an RFC as it seems worth checking we're happy with the implications of this, especially when it comes to changing RVA22. e.g. are we happy it won't confuse external tools, and do we forsee any issues from the canonical normalised ISA naming string for RVA22 now being different to what it was. I've listed this on the agenda for the next RISC-V LLVM sync call. Note: RVM23 doesn't currently use B, but I filed riscv/riscv-profiles#191 which I'd expect would be accepted. Full diff: https://github.com/llvm/llvm-project/pull/113942.diff 7 Files Affected:
diff --git a/clang/test/Driver/print-supported-extensions-riscv.c b/clang/test/Driver/print-supported-extensions-riscv.c
index e39847b9c31a8e..68acde65a74bfb 100644
--- a/clang/test/Driver/print-supported-extensions-riscv.c
+++ b/clang/test/Driver/print-supported-extensions-riscv.c
@@ -193,12 +193,12 @@
// CHECK-NEXT: rva22u64
// CHECK-NEXT: rva23s64
// CHECK-NEXT: rva23u64
+// CHECK-NEXT: rvb23s64
+// CHECK-NEXT: rvb23u64
// CHECK-NEXT: rvi20u32
// CHECK-NEXT: rvi20u64
// CHECK-EMPTY:
// CHECK-NEXT: Experimental Profiles
-// CHECK-NEXT: rvb23s64
-// CHECK-NEXT: rvb23u64
// CHECK-NEXT: rvm23u32
// CHECK-EMPTY:
// CHECK-NEXT: Use -march to specify the target's extension.
diff --git a/clang/test/Driver/riscv-profiles.c b/clang/test/Driver/riscv-profiles.c
index d85ac8baf4edd9..2b4d19422874cf 100644
--- a/clang/test/Driver/riscv-profiles.c
+++ b/clang/test/Driver/riscv-profiles.c
@@ -207,7 +207,7 @@
// RVA23S64: "-target-feature" "+svnapot"
// RVA23S64: "-target-feature" "+svpbmt"
-// RUN: %clang --target=riscv64 -### -c %s 2>&1 -march=rvb23u64 -menable-experimental-extensions \
+// RUN: %clang --target=riscv64 -### -c %s 2>&1 -march=rvb23u64 \
// RUN: | FileCheck -check-prefix=RVB23U64 %s
// RVB23U64: "-target-feature" "+m"
// RVB23U64: "-target-feature" "+a"
@@ -239,7 +239,7 @@
// RVB23U64: "-target-feature" "+zbs"
// RVB23U64: "-target-feature" "+zkt"
-// RUN: %clang --target=riscv64 -### -c %s 2>&1 -march=rvb23s64 -menable-experimental-extensions \
+// RUN: %clang --target=riscv64 -### -c %s 2>&1 -march=rvb23s64 \
// RUN: | FileCheck -check-prefix=RVB23S64 %s
// RVB23S64: "-target-feature" "+m"
// RVB23S64: "-target-feature" "+a"
diff --git a/llvm/docs/RISCVUsage.rst b/llvm/docs/RISCVUsage.rst
index 04f2c357766d44..f6f2eb45c49c17 100644
--- a/llvm/docs/RISCVUsage.rst
+++ b/llvm/docs/RISCVUsage.rst
@@ -84,6 +84,8 @@ ISA naming string. Currently supported profiles:
* ``rva22s64``
* ``rva23u64``
* ``rva23s64``
+* ``rvb23u64``
+* ``rvb23s64``
Note that you can also append additional extension names to be enabled, e.g.
``rva20u64_zicond`` will enable the ``zicond`` extension in addition to those
@@ -93,8 +95,6 @@ Profiles that are not yet ratified cannot be used unless
``-menable-experimental-extensions`` (or equivalent for other tools) is
specified. This applies to the following profiles:
-* ``rvb23u64``
-* ``rvb23s64``
* ``rvm23u32``
.. _riscv-extensions:
diff --git a/llvm/docs/ReleaseNotes.md b/llvm/docs/ReleaseNotes.md
index ac7a795daf791a..92a45d845f1db8 100644
--- a/llvm/docs/ReleaseNotes.md
+++ b/llvm/docs/ReleaseNotes.md
@@ -184,7 +184,8 @@ Changes to the RISC-V Backend
* The `Smmpm`, `Smnpm`, `Ssnpm`, `Supm`, and `Sspm` pointer masking extensions
are no longer marked as experimental.
* The `Sha` extension is now supported.
-* The RVA23U64 and RVA23S64 profiles are no longer marked as experimental.
+* The RVA23U64, RVA23S64, RVB23U64, and RVB23S64 profiles are no longer marked
+ as experimental.
Changes to the WebAssembly Backend
----------------------------------
diff --git a/llvm/lib/Target/RISCV/RISCVProfiles.td b/llvm/lib/Target/RISCV/RISCVProfiles.td
index ea0fe08abd7a14..bcb776e682aea7 100644
--- a/llvm/lib/Target/RISCV/RISCVProfiles.td
+++ b/llvm/lib/Target/RISCV/RISCVProfiles.td
@@ -45,9 +45,7 @@ defvar RVA22U64Features = !listconcat(RVA20U64BaseFeatures,
[FeatureStdExtZa64rs,
FeatureStdExtZihpm,
FeatureStdExtZihintpause,
- FeatureStdExtZba,
- FeatureStdExtZbb,
- FeatureStdExtZbs,
+ FeatureStdExtB,
FeatureStdExtZic64b,
FeatureStdExtZicbom,
FeatureStdExtZicbop,
@@ -92,9 +90,7 @@ defvar RVB23U64Features = !listconcat(RVA20U64BaseFeatures,
[FeatureStdExtZihpm,
FeatureStdExtZa64rs,
FeatureStdExtZihintpause,
- FeatureStdExtZba,
- FeatureStdExtZbb,
- FeatureStdExtZbs,
+ FeatureStdExtB,
FeatureStdExtZic64b,
FeatureStdExtZicbom,
FeatureStdExtZicbop,
@@ -128,9 +124,7 @@ defvar RVB23S64Features = !listconcat(RVB23U64Features,
defvar RVM23U32Features = [Feature32Bit,
FeatureStdExtI,
FeatureStdExtM,
- FeatureStdExtZba,
- FeatureStdExtZbb,
- FeatureStdExtZbs,
+ FeatureStdExtB,
FeatureStdExtZicond,
FeatureStdExtZihintpause,
FeatureStdExtZihintntl,
@@ -163,6 +157,6 @@ def RVA22U64 : RISCVProfile<"rva22u64", RVA22U64Features>;
def RVA22S64 : RISCVProfile<"rva22s64", RVA22S64Features>;
def RVA23U64 : RISCVProfile<"rva23u64", RVA23U64Features>;
def RVA23S64 : RISCVProfile<"rva23s64", RVA23S64Features>;
-def RVB23U64 : RISCVExperimentalProfile<"rvb23u64", RVB23U64Features>;
-def RVB23S64 : RISCVExperimentalProfile<"rvb23s64", RVB23S64Features>;
+def RVB23U64 : RISCVProfile<"rvb23u64", RVB23U64Features>;
+def RVB23S64 : RISCVProfile<"rvb23s64", RVB23S64Features>;
def RVM23U32 : RISCVExperimentalProfile<"rvm23u32", RVM23U32Features>;
diff --git a/llvm/test/CodeGen/RISCV/attributes.ll b/llvm/test/CodeGen/RISCV/attributes.ll
index 2545c7075e4cf5..8688009f492b94 100644
--- a/llvm/test/CodeGen/RISCV/attributes.ll
+++ b/llvm/test/CodeGen/RISCV/attributes.ll
@@ -293,8 +293,8 @@
; RUN: llc -mtriple=riscv64 -mattr=+rva22s64 %s -o - | FileCheck --check-prefix=RVA22S64 %s
; RUN: llc -mtriple=riscv64 -mattr=+rva23u64 %s -o - | FileCheck --check-prefix=RVA23U64 %s
; RUN: llc -mtriple=riscv64 -mattr=+rva23s64 %s -o - | FileCheck --check-prefix=RVA23S64 %s
-; RUN: llc -mtriple=riscv64 -mattr=+experimental-rvb23u64 %s -o - | FileCheck --check-prefix=RVB23U64 %s
-; RUN: llc -mtriple=riscv64 -mattr=+experimental-rvb23s64 %s -o - | FileCheck --check-prefix=RVB23S64 %s
+; RUN: llc -mtriple=riscv64 -mattr=+rvb23u64 %s -o - | FileCheck --check-prefix=RVB23U64 %s
+; RUN: llc -mtriple=riscv64 -mattr=+rvb23s64 %s -o - | FileCheck --check-prefix=RVB23S64 %s
; RUN: llc -mtriple=riscv32 -mattr=+experimental-rvm23u32 %s -o - | FileCheck --check-prefix=RVM23U32 %s
; CHECK: .attribute 4, 16
@@ -584,13 +584,13 @@
; RVI20U64: .attribute 5, "rv64i2p1"
; RVA20U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicsr2p0_zmmul1p0_za128rs1p0"
; RVA20S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicsr2p0_zifencei2p0_zmmul1p0_za128rs1p0_ssccptr1p0_sstvala1p0_sstvecd1p0_svade1p0_svbare1p0"
-; RVA22U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicsr2p0_zihintpause2p0_zihpm2p0_zmmul1p0_za64rs1p0_zfhmin1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0"
-; RVA22S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicsr2p0_zifencei2p0_zihintpause2p0_zihpm2p0_zmmul1p0_za64rs1p0_zfhmin1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_ssccptr1p0_sscounterenw1p0_sstvala1p0_sstvecd1p0_svade1p0_svbare1p0_svinval1p0_svpbmt1p0"
-; RVA23U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_v1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zfhmin1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_zvbb1p0_zve32f1p0_zve32x1p0_zve64d1p0_zve64f1p0_zve64x1p0_zvfhmin1p0_zvkb1p0_zvkt1p0_zvl128b1p0_zvl32b1p0_zvl64b1p0_supm1p0"
-; RVA23S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_v1p0_h1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zifencei2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zfhmin1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_zvbb1p0_zve32f1p0_zve32x1p0_zve64d1p0_zve64f1p0_zve64x1p0_zvfhmin1p0_zvkb1p0_zvkt1p0_zvl128b1p0_zvl32b1p0_zvl64b1p0_sha1p0_shcounterenw1p0_shgatpa1p0_shtvala1p0_shvsatpa1p0_shvstvala1p0_shvstvecd1p0_ssccptr1p0_sscofpmf1p0_sscounterenw1p0_ssnpm1p0_ssstateen1p0_sstc1p0_sstvala1p0_sstvecd1p0_ssu64xl1p0_supm1p0_svade1p0_svbare1p0_svinval1p0_svnapot1p0_svpbmt1p0"
-; RVB23U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0"
-; RVB23S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zifencei2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_ssccptr1p0_sscofpmf1p0_sscounterenw1p0_sstc1p0_sstvala1p0_sstvecd1p0_ssu64xl1p0_svade1p0_svbare1p0_svinval1p0_svnapot1p0_svpbmt1p0"
-; RVM23U32: .attribute 5, "rv32i2p1_m2p0_zicbop1p0_zicond1p0_zicsr2p0_zihintntl1p0_zihintpause2p0_zimop1p0_zmmul1p0_zca1p0_zcb1p0_zce1p0_zcmop1p0_zcmp1p0_zcmt1p0_zba1p0_zbb1p0_zbs1p0"
+; RVA22U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_b1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicsr2p0_zihintpause2p0_zihpm2p0_zmmul1p0_za64rs1p0_zfhmin1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0"
+; RVA22S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_b1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicsr2p0_zifencei2p0_zihintpause2p0_zihpm2p0_zmmul1p0_za64rs1p0_zfhmin1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_ssccptr1p0_sscounterenw1p0_sstvala1p0_sstvecd1p0_svade1p0_svbare1p0_svinval1p0_svpbmt1p0"
+; RVA23U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_b1p0_v1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zfhmin1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_zvbb1p0_zve32f1p0_zve32x1p0_zve64d1p0_zve64f1p0_zve64x1p0_zvfhmin1p0_zvkb1p0_zvkt1p0_zvl128b1p0_zvl32b1p0_zvl64b1p0_supm1p0"
+; RVA23S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_b1p0_v1p0_h1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zifencei2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zfhmin1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_zvbb1p0_zve32f1p0_zve32x1p0_zve64d1p0_zve64f1p0_zve64x1p0_zvfhmin1p0_zvkb1p0_zvkt1p0_zvl128b1p0_zvl32b1p0_zvl64b1p0_sha1p0_shcounterenw1p0_shgatpa1p0_shtvala1p0_shvsatpa1p0_shvstvala1p0_shvstvecd1p0_ssccptr1p0_sscofpmf1p0_sscounterenw1p0_ssnpm1p0_ssstateen1p0_sstc1p0_sstvala1p0_sstvecd1p0_ssu64xl1p0_supm1p0_svade1p0_svbare1p0_svinval1p0_svnapot1p0_svpbmt1p0"
+; RVB23U64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_b1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0"
+; RVB23S64: .attribute 5, "rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_b1p0_zic64b1p0_zicbom1p0_zicbop1p0_zicboz1p0_ziccamoa1p0_ziccif1p0_zicclsm1p0_ziccrse1p0_zicntr2p0_zicond1p0_zicsr2p0_zifencei2p0_zihintntl1p0_zihintpause2p0_zihpm2p0_zimop1p0_zmmul1p0_za64rs1p0_zawrs1p0_zfa1p0_zca1p0_zcb1p0_zcmop1p0_zba1p0_zbb1p0_zbs1p0_zkt1p0_ssccptr1p0_sscofpmf1p0_sscounterenw1p0_sstc1p0_sstvala1p0_sstvecd1p0_ssu64xl1p0_svade1p0_svbare1p0_svinval1p0_svnapot1p0_svpbmt1p0"
+; RVM23U32: .attribute 5, "rv32i2p1_m2p0_b1p0_zicbop1p0_zicond1p0_zicsr2p0_zihintntl1p0_zihintpause2p0_zimop1p0_zmmul1p0_zca1p0_zcb1p0_zce1p0_zcmop1p0_zcmp1p0_zcmt1p0_zba1p0_zbb1p0_zbs1p0"
define i32 @addi(i32 %a) {
%1 = add i32 %a, 1
diff --git a/llvm/unittests/TargetParser/RISCVISAInfoTest.cpp b/llvm/unittests/TargetParser/RISCVISAInfoTest.cpp
index 48792ad0265fc4..a1d493e12fda6d 100644
--- a/llvm/unittests/TargetParser/RISCVISAInfoTest.cpp
+++ b/llvm/unittests/TargetParser/RISCVISAInfoTest.cpp
@@ -1138,12 +1138,12 @@ Supported Profiles
rva22u64
rva23s64
rva23u64
+ rvb23s64
+ rvb23u64
rvi20u32
rvi20u64
Experimental Profiles
- rvb23s64
- rvb23u64
rvm23u32
Use -march to specify the target's extension.
|
|
I think we shouldn't do this for RVA22, so as not to break existing users of that profile, who may have a toolchain that doesn't support B. This change makes sense to me for the RV*23 profiles, especially since your change to RVM23 has been accepted. |
|
The change should be reflected in the -target-feature checks in clang/test/Driver/riscv-profiles.c too. |
For RVA22, I had a look at the commit history for extension support in binutils. From what I can see (@kito-cheng please correct me if I'm wrong):
So given we emit zic64b anyway (as it has always been in the RVA22 spec), I think we probably do have freedom to add in B here without breaking binutils that would have previously successfully assembled our rva22u64 output. |
Alright, then I don't have any worries about RVA22. |
asb
changed the title
|
I've added the CHECK lines to riscv-profiles.c as spotted by @topperc, and based on the above discussion I think this is now ready to review. |
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/52/builds/3611 Here is the relevant piece of the build log for the reference |
|
Sorry I didn't get to this over the weekend. LGTM. |
Groverkss
pushed a commit
to iree-org/llvm-project
that referenced
this pull request
Nov 15, 2024
) RVA22 has retroactively been defined as including 'B' (as it's a shorthand for Zba+Zbb+Zbs, which were previously explicitly enumerated) and RV{A,B,M}23 are defined featuring B. We don't currently infer B whenever Zba+Zbb+Zbs are present due to concerns about compatibility with external assemblers such as gas. We don't believe that adding B to RVA22 will cause issues for users who (for instance) build with clang and assemble with binutils as looking at the binutils commit history: zic64b support was only committed in 25f05199bb7e35820c23e802424484accb7936b1 in July 2024 B support was committed in c144f638337944101131d9fe6de4ab908f6d4c2d in May 2024 So given we emit zic64b anyway (as it has always been in the RVA22 spec), no binutils that would have previously successfully assembled our rva22u64 output should fail due to the addition of 'B'.
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RVA22 has retroactively been defined as including 'B' (as it's a
shorthand for Zba+Zbb+Zbs, which were previously explicitly enumerated)
and RV{A,B,M}23 are defined featuring B. We don't currently infer B
whenever Zba+Zbb+Zbs are present due to concerns about compatibility
with external assemblers such as gas.
We don't believe that adding B to RVA22 will cause issues for users who (for instance) build with clang and assemble with binutils as looking at the binutils commit history:
zic64b support was only committed in 25f05199bb7e35820c23e802424484accb7936b1 in July 2024
B support was committed in c144f638337944101131d9fe6de4ab908f6d4c2d in May 2024
So given we emit zic64b anyway (as it has always been in the RVA22 spec), no binutils that would have previously successfully assembled our rva22u64 output should fail due to the addition of 'B'.
Note: This was initially posted as an RFC but is now ready for review