[RISCV] Add -mcpu=sifive-p550.

This is the CPU in SiFive's HiFive Premier P550 development board.

Scheduler model will come in a later patch.

Author: topperc

clang/test/Driver/riscv-cpus.c

@@ -433,6 +433,19 @@
 // MCPU-SIFIVE-P470-SAME: "-target-feature" "+zvkt"
 // MCPU-SIFIVE-P470-SAME: "-target-abi" "lp64d"
 
+// RUN: %clang -target riscv64 -### -c %s 2>&1 -mcpu=sifive-p550 | FileCheck -check-prefix=MCPU-SIFIVE-P550 %s
+// MCPU-SIFIVE-P550: "-nostdsysteminc" "-target-cpu" "sifive-p550"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+m"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+a"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+f"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+d"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+c"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+zicsr"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+zifencei"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+zba"
+// MCPU-SIFIVE-P550-SAME: "-target-feature" "+zbb"
+// MCPU-SIFIVE-P550-SAME: "-target-abi" "lp64d"
+
 // RUN: %clang -target riscv64 -### -c %s 2>&1 -mcpu=sifive-p670 | FileCheck -check-prefix=MCPU-SIFIVE-P670 %s
 // MCPU-SIFIVE-P670: "-target-cpu" "sifive-p670"
 // MCPU-SIFIVE-P670-SAME: "-target-feature" "+m"

clang/test/Misc/target-invalid-cpu-note/riscv.c

@@ -29,6 +29,7 @@
 // RISCV64-SAME: {{^}}, rocket-rv64
 // RISCV64-SAME: {{^}}, sifive-p450
 // RISCV64-SAME: {{^}}, sifive-p470
+// RISCV64-SAME: {{^}}, sifive-p550
 // RISCV64-SAME: {{^}}, sifive-p670
 // RISCV64-SAME: {{^}}, sifive-s21
 // RISCV64-SAME: {{^}}, sifive-s51
@@ -77,6 +78,7 @@
 // TUNE-RISCV64-SAME: {{^}}, rocket-rv64
 // TUNE-RISCV64-SAME: {{^}}, sifive-p450
 // TUNE-RISCV64-SAME: {{^}}, sifive-p470
+// TUNE-RISCV64-SAME: {{^}}, sifive-p550
 // TUNE-RISCV64-SAME: {{^}}, sifive-p670
 // TUNE-RISCV64-SAME: {{^}}, sifive-s21
 // TUNE-RISCV64-SAME: {{^}}, sifive-s51

llvm/docs/ReleaseNotes.md

@@ -198,6 +198,7 @@ Changes to the RISC-V Backend
 * `-mcpu=syntacore-scr7` was added.
 * `-mcpu=tt-ascalon-d8` was added.
 * `-mcpu=mips-p8700` was added.
+* `-mcpu=sifive-p550` was added.
 * The `Zacas` extension is no longer marked as experimental.
 * Added Smdbltrp, Ssdbltrp extensions to -march.
 * The `Smmpm`, `Smnpm`, `Ssnpm`, `Supm`, and `Sspm` pointer masking extensions

llvm/lib/Target/RISCV/RISCVProcessors.td

@@ -321,6 +321,25 @@ def SIFIVE_P470 : RISCVProcessorModel<"sifive-p470", SiFiveP400Model,
                                                   [TuneNoSinkSplatOperands,
                                                    TuneVXRMPipelineFlush])>;
 
+defvar SiFiveP500TuneFeatures = [TuneNoDefaultUnroll,
+                                 TuneConditionalCompressedMoveFusion,
+                                 TuneLUIADDIFusion,
+                                 TuneAUIPCADDIFusion,
+                                 TunePostRAScheduler];
+
+def SIFIVE_P550 : RISCVProcessorModel<"sifive-p550", NoSchedModel,
+                                      [Feature64Bit,
+                                       FeatureStdExtI,
+                                       FeatureStdExtZifencei,
+                                       FeatureStdExtM,
+                                       FeatureStdExtA,
+                                       FeatureStdExtF,
+                                       FeatureStdExtD,
+                                       FeatureStdExtC,
+                                       FeatureStdExtZba,
+                                       FeatureStdExtZbb],
+                                      SiFiveP500TuneFeatures>;
+
 def SIFIVE_P670 : RISCVProcessorModel<"sifive-p670", SiFiveP600Model,
                                       !listconcat(RVA22U64Features,
                                       [FeatureStdExtV,