Add implies of Zicifss.

Author: Yeting Kuo

llvm/lib/Support/RISCVISAInfo.cpp

@@ -1024,6 +1024,7 @@ static const char *ImpliedExtsZfinx[] = {"zicsr"};
 static const char *ImpliedExtsZhinx[] = {"zhinxmin"};
 static const char *ImpliedExtsZhinxmin[] = {"zfinx"};
 static const char *ImpliedExtsZicntr[] = {"zicsr"};
+static const char *ImpliedExtsZicfiss[] = {"zicsr", "zimop", "zcmop"};
 static const char *ImpliedExtsZihpm[] = {"zicsr"};
 static const char *ImpliedExtsZk[] = {"zkn", "zkt", "zkr"};
 static const char *ImpliedExtsZkn[] = {"zbkb", "zbkc", "zbkx",
@@ -1096,6 +1097,7 @@ static constexpr ImpliedExtsEntry ImpliedExts[] = {
     {{"zfinx"}, {ImpliedExtsZfinx}},
     {{"zhinx"}, {ImpliedExtsZhinx}},
     {{"zhinxmin"}, {ImpliedExtsZhinxmin}},
+    {{"zicfiss"}, {ImpliedExtsZicfiss}},
     {{"zicntr"}, {ImpliedExtsZicntr}},
     {{"zihpm"}, {ImpliedExtsZihpm}},
     {{"zk"}, {ImpliedExtsZk}},

llvm/lib/Target/RISCV/RISCVFeatures.td

@@ -79,13 +79,6 @@ def HasStdExtZihintntl : Predicate<"Subtarget->hasStdExtZihintntl()">,
                                     AssemblerPredicate<(all_of FeatureStdExtZihintntl),
                                     "'Zihintntl' (Non-Temporal Locality Hints)">;
 
-def FeatureStdExtZicfiss
-    : SubtargetFeature<"experimental-zicfiss", "HasStdExtZicfiss", "true",
-                       "'Zicfiss' (Shadow stack)">;
-def HasStdExtZicfiss : Predicate<"Subtarget->hasStdExtZicfiss()">,
-                                 AssemblerPredicate<(all_of FeatureStdExtZicfiss),
-                                 "'Zicfiss' (Shadow stack)">;
-
 def FeatureStdExtZifencei
     : SubtargetFeature<"zifencei", "HasStdExtZifencei", "true",
                        "'Zifencei' (fence.i)">;
@@ -707,6 +700,14 @@ def HasStdExtZcmop : Predicate<"Subtarget->hasStdExtZcmop()">,
                                AssemblerPredicate<(all_of FeatureStdExtZcmop),
                                "'Zcmop' (Compressed May-Be-Operations)">;
 
+def FeatureStdExtZicfiss
+    : SubtargetFeature<"experimental-zicfiss", "HasStdExtZicfiss", "true",
+                       "'Zicfiss' (Shadow stack)",
+                       [FeatureStdExtZicsr, FeatureStdExtZimop, FeatureStdExtZcmop]>;
+def HasStdExtZicfiss : Predicate<"Subtarget->hasStdExtZicfiss()">,
+                                 AssemblerPredicate<(all_of FeatureStdExtZicfiss),
+                                 "'Zicfiss' (Shadow stack)">;
+
 def FeatureStdExtSmaia
     : SubtargetFeature<"smaia", "HasStdExtSmaia", "true",
                        "'Smaia' (Smaia encompasses all added CSRs and all "

llvm/test/MC/RISCV/attribute-arch.s

@@ -313,7 +313,7 @@
 # CHECK: attribute      5, "rv32i2p1_zicfilp0p4"
 
 .attribute arch, "rv32i_zicfiss0p4"
-# CHECK: .attribute     5, "rv32i2p1_zicfiss0p4"
+# CHECK: .attribute     5, "rv32i2p1_zicfiss0p4_zicsr2p0_zimop0p1_zca1p0_zcmop0p2"
 
 .attribute arch, "rv64i_xsfvfwmaccqqq"
 # CHECK: attribute      5, "rv64i2p1_f2p2_zicsr2p0_zve32f1p0_zve32x1p0_zvfbfmin0p8_zvl32b1p0_xsfvfwmaccqqq1p0"

llvm/test/MC/RISCV/compressed-zicfiss.s

@@ -100,3 +100,23 @@ ssamoswap.d.rl a4, ra, (s0)
 # CHECK-NO-EXT-RV64: error: instruction requires the following: 'Zicfiss' (Shadow stack)
 ssamoswap.d.aqrl a4, ra, (s0)
 .endif
+
+# CHECK-ASM-AND-OBJ: c.sspush ra
+# CHECK-ASM: encoding: [0x81,0x60]
+# CHECK-NO-EXT: error: instruction requires the following: 'Zicfiss' (Shadow stack)
+c.sspush x1
+
+# CHECK-ASM-AND-OBJ: c.sspush ra
+# CHECK-ASM: encoding: [0x81,0x60]
+# CHECK-NO-EXT: error: instruction requires the following: 'Zicfiss' (Shadow stack)
+c.sspush ra
+
+# CHECK-ASM-AND-OBJ: c.sspopchk t0
+# CHECK-ASM: encoding: [0x81,0x62]
+# CHECK-NO-EXT: error: instruction requires the following: 'Zicfiss' (Shadow stack)
+c.sspopchk x5
+
+# CHECK-ASM-AND-OBJ: c.sspopchk t0
+# CHECK-ASM: encoding: [0x81,0x62]
+# CHECK-NO-EXT: error: instruction requires the following: 'Zicfiss' (Shadow stack)
+c.sspopchk t0