cmd/internal/obj/riscv: improve instruction validation

Ensure that rs2 is none for various instruction encodings. Fix a couple of cases
where it should have been but is not.

Change-Id: I9f8211a0257e49643dbbc89e158e048050ebe6f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/349649
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>

diff --git a/src/cmd/internal/obj/riscv/obj.go b/src/cmd/internal/obj/riscv/obj.go
index 62d44d8a3f239bdf13aa35f07bb14b3af1f25caa..f0ea21de97f43226ae411afccb360903f4fe4370 100644 (file)
--- a/src/cmd/internal/obj/riscv/obj.go
+++ b/src/cmd/internal/obj/riscv/obj.go
@@ -1003,6 +1003,7 @@ func validateII(ctxt *obj.Link, ins *instruction) {
        wantImmI(ctxt, ins.as, ins.imm, 12)
        wantIntReg(ctxt, ins.as, "rd", ins.rd)
        wantIntReg(ctxt, ins.as, "rs1", ins.rs1)
+       wantNoneReg(ctxt, ins.as, "rs2", ins.rs2)
        wantNoneReg(ctxt, ins.as, "rs3", ins.rs3)
 }
 
@@ -1010,6 +1011,7 @@ func validateIF(ctxt *obj.Link, ins *instruction) {
        wantImmI(ctxt, ins.as, ins.imm, 12)
        wantFloatReg(ctxt, ins.as, "rd", ins.rd)
        wantIntReg(ctxt, ins.as, "rs1", ins.rs1)
+       wantNoneReg(ctxt, ins.as, "rs2", ins.rs2)
        wantNoneReg(ctxt, ins.as, "rs3", ins.rs3)
 }
 
@@ -1017,6 +1019,7 @@ func validateSI(ctxt *obj.Link, ins *instruction) {
        wantImmI(ctxt, ins.as, ins.imm, 12)
        wantIntReg(ctxt, ins.as, "rd", ins.rd)
        wantIntReg(ctxt, ins.as, "rs1", ins.rs1)
+       wantNoneReg(ctxt, ins.as, "rs2", ins.rs2)
        wantNoneReg(ctxt, ins.as, "rs3", ins.rs3)
 }
 
@@ -1024,6 +1027,7 @@ func validateSF(ctxt *obj.Link, ins *instruction) {
        wantImmI(ctxt, ins.as, ins.imm, 12)
        wantIntReg(ctxt, ins.as, "rd", ins.rd)
        wantFloatReg(ctxt, ins.as, "rs1", ins.rs1)
+       wantNoneReg(ctxt, ins.as, "rs2", ins.rs2)
        wantNoneReg(ctxt, ins.as, "rs3", ins.rs3)
 }
 
@@ -1567,7 +1571,7 @@ func instructionForProg(p *obj.Prog) *instruction {
 func instructionsForOpImmediate(p *obj.Prog, as obj.As, rs int16) []*instruction {
        // <opi> $imm, REG, TO
        ins := instructionForProg(p)
-       ins.as, ins.rs1 = as, uint32(rs)
+       ins.as, ins.rs1, ins.rs2 = as, uint32(rs), obj.REG_NONE
 
        low, high, err := Split32BitImmediate(ins.imm)
        if err != nil {
@@ -1990,7 +1994,7 @@ func instructionsForProg(p *obj.Prog) []*instruction {
        case ASEQZ:
                // SEQZ rs, rd -> SLTIU $1, rs, rd
                ins.as = ASLTIU
-               ins.rs1 = uint32(p.From.Reg)
+               ins.rs1, ins.rs2 = uint32(p.From.Reg), obj.REG_NONE
                ins.imm = 1
 
        case ASNEZ: