[RISCV] Promote s32 G_SEXT_INREG for RV64

Author: topperc

llvm/lib/Target/RISCV/GISel/RISCVLegalizerInfo.cpp

@@ -159,19 +159,15 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST)
                        typeIsLegalIntOrFPVec(1, IntOrFPVecTys, ST)));
   if (ST.is64Bit()) {
     ExtActions.legalFor({{sXLen, s32}});
-    getActionDefinitionsBuilder(G_SEXT_INREG)
-        .customFor({s32, sXLen})
-        .maxScalar(0, sXLen)
-        .lower();
-  } else {
-    getActionDefinitionsBuilder(G_SEXT_INREG)
-        .customFor({s32})
-        .maxScalar(0, sXLen)
-        .lower();
   }
   ExtActions.customIf(typeIsLegalBoolVec(1, BoolVecTys, ST))
       .maxScalar(0, sXLen);
 
+  getActionDefinitionsBuilder(G_SEXT_INREG)
+      .customFor({sXLen})
+      .clampScalar(0, sXLen, sXLen)
+      .lower();
+
   // Merge/Unmerge
   for (unsigned Op : {G_MERGE_VALUES, G_UNMERGE_VALUES}) {
     auto &MergeUnmergeActions = getActionDefinitionsBuilder(Op);

llvm/lib/Target/RISCV/RISCVGISel.td

@@ -218,11 +218,6 @@ def : Pat<(shl (zext GPR:$rs), uimm5:$shamt),
 // Zb* RV64 i32 patterns not used by SelectionDAG.
 //===----------------------------------------------------------------------===//
 
-let Predicates = [HasStdExtZbb, IsRV64] in {
-def : Pat<(i32 (sext_inreg GPR:$rs1, i8)), (SEXT_B GPR:$rs1)>;
-def : Pat<(i32 (sext_inreg GPR:$rs1, i16)), (SEXT_H GPR:$rs1)>;
-} // Predicates = [HasStdExtZbb, IsRV64]
-
 let Predicates = [HasStdExtZba, IsRV64] in {
 def : Pat<(shl (i64 (zext GPR:$rs1)), uimm5:$shamt),
           (SLLI_UW GPR:$rs1, uimm5:$shamt)>;

llvm/test/CodeGen/RISCV/GlobalISel/rv64zbb.ll

@@ -869,8 +869,8 @@ define i64 @ctpop_i64(i64 %a) nounwind {
 define signext i32 @sextb_i32(i32 signext %a) nounwind {
 ; RV64I-LABEL: sextb_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a0, a0, 24
-; RV64I-NEXT:    sraiw a0, a0, 24
+; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srai a0, a0, 56
 ; RV64I-NEXT:    ret
 ;
 ; RV64ZBB-LABEL: sextb_i32:
@@ -901,8 +901,8 @@ define i64 @sextb_i64(i64 %a) nounwind {
 define signext i32 @sexth_i32(i32 signext %a) nounwind {
 ; RV64I-LABEL: sexth_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a0, a0, 16
-; RV64I-NEXT:    sraiw a0, a0, 16
+; RV64I-NEXT:    slli a0, a0, 48
+; RV64I-NEXT:    srai a0, a0, 48
 ; RV64I-NEXT:    ret
 ;
 ; RV64ZBB-LABEL: sexth_i32: