fix isCall flag for JAL and JALR, and the isBranch flag for C_JR

[moste00]

Fixes #161104

[github-actions]

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[llvmbot]

@llvm/pr-subscribers-backend-risc-v

Author: مصطفي محمود كمال الدين (moste00)

Changes

Fixes #161104

---

Full diff: https://github.com/llvm/llvm-project/pull/161105.diff

2 Files Affected:

• (modified) llvm/lib/Target/RISCV/RISCVInstrInfo.td (+8-6)
• (modified) llvm/lib/Target/RISCV/RISCVInstrInfoC.td (+1)

diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfo.td b/llvm/lib/Target/RISCV/RISCVInstrInfo.td
index 9855c47a63392..3aa65cfb4c556 100644
--- a/llvm/lib/Target/RISCV/RISCVInstrInfo.td
+++ b/llvm/lib/Target/RISCV/RISCVInstrInfo.td
@@ -752,13 +752,15 @@ def LUI : RVInstU<OPC_LUI, (outs GPR:$rd), (ins uimm20_lui:$imm20),
 def AUIPC : RVInstU<OPC_AUIPC, (outs GPR:$rd), (ins uimm20_auipc:$imm20),
                     "auipc", "$rd, $imm20">, Sched<[WriteIALU]>;
 
-def JAL : RVInstJ<OPC_JAL, (outs GPR:$rd), (ins simm21_lsb0_jal:$imm20),
-                  "jal", "$rd, $imm20">, Sched<[WriteJal]>;
+    let isCall = 1 in {
+    def JAL : RVInstJ<OPC_JAL, (outs GPR:$rd), (ins simm21_lsb0_jal:$imm20),
+                    "jal", "$rd, $imm20">, Sched<[WriteJal]>;
 
-def JALR : RVInstI<0b000, OPC_JALR, (outs GPR:$rd),
-                   (ins GPR:$rs1, simm12_lo:$imm12),
-                   "jalr", "$rd, ${imm12}(${rs1})">,
-           Sched<[WriteJalr, ReadJalr]>;
+    def JALR : RVInstI<0b000, OPC_JALR, (outs GPR:$rd),
+                    (ins GPR:$rs1, simm12_lo:$imm12),
+                    "jalr", "$rd, ${imm12}(${rs1})">,
+            Sched<[WriteJalr, ReadJalr]>;
+    }
 } // hasSideEffects = 0, mayLoad = 0, mayStore = 0
 
 def BEQ  : BranchCC_rri<0b000, "beq">;
diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfoC.td b/llvm/lib/Target/RISCV/RISCVInstrInfoC.td
index 24e7a0ee5a79f..fadea31075d37 100644
--- a/llvm/lib/Target/RISCV/RISCVInstrInfoC.td
+++ b/llvm/lib/Target/RISCV/RISCVInstrInfoC.td
@@ -488,6 +488,7 @@ def C_LDSP : CStackLoad<0b011, "c.ldsp", GPRNoX0, uimm9_lsb000>,
 let hasSideEffects = 0, mayLoad = 0, mayStore = 0 in
 def C_JR : RVInst16CR<0b1000, 0b10, (outs), (ins GPRNoX0:$rs1),
                       "c.jr", "$rs1">, Sched<[WriteJalr, ReadJalr]> {
+  let isBranch = 1;
   let isBarrier = 1;
   let isTerminator = 1;
   let rs2 = 0;

[topperc]

Both of these instructions are not a call if the destination is X0. The RET pseudoinstruciton for example is JALR with rd=x0 and rs1=x0.

[topperc]

c.jr is not a branch if rs1=x1. It's a return.