commit ed5a770b3e9e288fe375e448fb74798719325b56
author Hsiangkai Wang <kai.wang@sifive.com> Thu Feb 18 14:52:19 2021 +0800
committer Copybara-Service <copybara-worker@google.com> Fri Feb 19 03:30:25 2021 -0800
tree 3aac308195ec8d78ffb44067093e60688db37ee1
parent 6b03ec73557b98bb87bfea9be97a50b9d55a4ac7

[RISCV] Fix bugs in pseudo instructions for masked segment load.

For masked segment load, the destination register should not overlap
with mask register. It could not be V0.

In the original implementation, there is no segment load/store register
class without V0. In this patch, I added these register classes and
modify `GetVRegNoV0` to get the correct one.

Differential Revision: https://reviews.llvm.org/D96937

GitOrigin-RevId: f1efa8abaf8e4fac5ef37aeb10d607ceecdb4ece

lib/Target/RISCV/RISCVInstrInfoVPseudos.td

diff --git a/lib/Target/RISCV/RISCVInstrInfoVPseudos.td b/lib/Target/RISCV/RISCVInstrInfoVPseudos.td
index 4b93a37..2b4e9f9 100644
--- a/lib/Target/RISCV/RISCVInstrInfoVPseudos.td
+++ b/lib/Target/RISCV/RISCVInstrInfoVPseudos.td
@@ -492,7 +492,18 @@
                  !eq(VRegClass, VRM2) : VRM2NoV0,
                  !eq(VRegClass, VRM4) : VRM4NoV0,
                  !eq(VRegClass, VRM8) : VRM8NoV0,
-                 !eq(1, 1) : VRegClass);
+                 !eq(VRegClass, VRN2M1) : VRN2M1NoV0,
+                 !eq(VRegClass, VRN2M2) : VRN2M2NoV0,
+                 !eq(VRegClass, VRN2M4) : VRN2M4NoV0,
+                 !eq(VRegClass, VRN3M1) : VRN3M1NoV0,
+                 !eq(VRegClass, VRN3M2) : VRN3M2NoV0,
+                 !eq(VRegClass, VRN4M1) : VRN4M1NoV0,
+                 !eq(VRegClass, VRN4M2) : VRN4M2NoV0,
+                 !eq(VRegClass, VRN5M1) : VRN5M1NoV0,
+                 !eq(VRegClass, VRN6M1) : VRN6M1NoV0,
+                 !eq(VRegClass, VRN7M1) : VRN7M1NoV0,
+                 !eq(VRegClass, VRN8M1) : VRN8M1NoV0,
+                 true : VRegClass);
 }
 
 // Join strings in list using separator and ignoring empty elements

lib/Target/RISCV/RISCVRegisterInfo.td

diff --git a/lib/Target/RISCV/RISCVRegisterInfo.td b/lib/Target/RISCV/RISCVRegisterInfo.td
index 5227220..e13468f 100644
--- a/lib/Target/RISCV/RISCVRegisterInfo.td
+++ b/lib/Target/RISCV/RISCVRegisterInfo.td
@@ -394,18 +394,24 @@
                               ), [!mul(i, lmul)], [])));
 }
 
-class VRegList<list<dag> LIn, int start, int nf, int lmul> {
+class VRegList<list<dag> LIn, int start, int nf, int lmul, bit NoV0> {
   list<dag> L =
     !if(!ge(start, nf),
         LIn,
         !listconcat(
           [!dag(add,
-                !foreach(i, IndexSet<start, nf, lmul>.R,
-                         !cast<Register>("V" # i # !cond(!eq(lmul, 2): "M2",
-                                                         !eq(lmul, 4): "M4",
-                                                         true: ""))),
-                !listsplat("", !size(IndexSet<start, nf, lmul>.R)))],
-          VRegList<LIn, !add(start, 1), nf, lmul>.L));
+                !foreach(i,
+                  !if(NoV0,
+                    !tail(IndexSet<start, nf, lmul>.R),
+                    [!head(IndexSet<start, nf, lmul>.R)]),
+                  !cast<Register>("V" # i # !cond(!eq(lmul, 2): "M2",
+                                                  !eq(lmul, 4): "M4",
+                                                  true: ""))),
+                !listsplat("",
+                  !if(NoV0,
+                    !size(!tail(IndexSet<start, nf, lmul>.R)),
+                    !size([!head(IndexSet<start, nf, lmul>.R)]))))],
+          VRegList<LIn, !add(start, 1), nf, lmul, NoV0>.L));
 }
 
 // Vector registers
@@ -453,8 +459,12 @@
 
 foreach m = [1, 2, 4] in {
   foreach n = NFList<m>.L in {
-    def "VN" # n # "M" # m: RegisterTuples<SubRegSet<[], 0, n, m>.L,
-                                           VRegList<[], 0, n, m>.L>;
+    def "VN" # n # "M" # m # "NoV0": RegisterTuples<
+                                       SubRegSet<[], 0, n, m>.L,
+                                       VRegList<[], 0, n, m, 1>.L>;
+    def "VN" # n # "M" # m # "V0" : RegisterTuples<
+                                       SubRegSet<[], 0, n, m>.L,
+                                       VRegList<[], 0, n, m, 0>.L>;
   }
 }
 
@@ -524,8 +534,11 @@
 
 foreach m = LMULList.m in {
   foreach nf = NFList<m>.L in {
-    def "VRN" # nf # "M" # m : VReg<[untyped],
-                               (add !cast<RegisterTuples>("VN" # nf # "M" # m)),
+    def "VRN" # nf # "M" # m: VReg<[untyped],
+                               (add !cast<RegisterTuples>("VN" # nf # "M" # m # "V0"), !cast<RegisterTuples>("VN" # nf # "M" # m # "NoV0")),
+                                    !mul(nf, m)>;
+    def "VRN" # nf # "M" # m # "NoV0": VReg<[untyped],
+                               (add !cast<RegisterTuples>("VN" # nf # "M" # m # "NoV0")),
                                     !mul(nf, m)>;
   }
 }