[llvm] b39ab2e - [RISCV] Use PADD_DW instead of ADDD for GPRPair copy on RV32 with P extension (#181316)

[via llvm-commits]

Author: Craig Topper
Date: 2026-02-13T09:41:08-08:00
New Revision: b39ab2e0ef601f563ec0ab0ae384b9b08730073a

URL: https://github.com/llvm/llvm-project/commit/b39ab2e0ef601f563ec0ab0ae384b9b08730073a
DIFF: https://github.com/llvm/llvm-project/commit/b39ab2e0ef601f563ec0ab0ae384b9b08730073a.diff

LOG: [RISCV] Use PADD_DW instead of ADDD for GPRPair copy on RV32 with P extension (#181316)

Added: 
    

Modified: 
    llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
    llvm/test/CodeGen/RISCV/make-compressible-zilsd.mir

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp b/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
index 0dfff7ee7d00c..2b496b1b20318 100644
--- a/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
+++ b/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
@@ -542,8 +542,8 @@ void RISCVInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
       }
 
       if (STI.hasStdExtP()) {
-        // On RV32P, `addd` is a GPR Pair Add
-        BuildMI(MBB, MBBI, DL, get(RISCV::ADDD), DstReg)
+        // On RV32P, `padd.dw` is a GPR Pair Add
+        BuildMI(MBB, MBBI, DL, get(RISCV::PADD_DW), DstReg)
             .addReg(SrcReg, KillFlag | getRenamableRegState(RenamableSrc))
             .addReg(RISCV::X0_Pair);
         return;

diff  --git a/llvm/test/CodeGen/RISCV/make-compressible-zilsd.mir b/llvm/test/CodeGen/RISCV/make-compressible-zilsd.mir
index 897f215cee525..0c22db20d4a68 100644
--- a/llvm/test/CodeGen/RISCV/make-compressible-zilsd.mir
+++ b/llvm/test/CodeGen/RISCV/make-compressible-zilsd.mir
@@ -130,7 +130,7 @@ body:             |
     ; RV32_P-LABEL: name: store_common_value_double
     ; RV32_P: liveins: $x10, $x11, $x12, $x16, $x17
     ; RV32_P-NEXT: {{  $}}
-    ; RV32_P-NEXT: $x14_x15 = ADDD $x16_x17, $x0_pair
+    ; RV32_P-NEXT: $x14_x15 = PADD_DW $x16_x17, $x0_pair
     ; RV32_P-NEXT: SD_RV32 $x14_x15, killed renamable $x10, 0 :: (store (s64) into %ir.a)
     ; RV32_P-NEXT: SD_RV32 $x14_x15, killed renamable $x11, 0 :: (store (s64) into %ir.b)
     ; RV32_P-NEXT: SD_RV32 killed $x14_x15, killed renamable $x12, 0 :: (store (s64) into %ir.c)
@@ -160,7 +160,7 @@ body:             |
     ; RV32_P-LABEL: name: store_common_value_double_zero
     ; RV32_P: liveins: $x10, $x11, $x12
     ; RV32_P-NEXT: {{  $}}
-    ; RV32_P-NEXT: $x14_x15 = ADDD $x0_pair, $x0_pair
+    ; RV32_P-NEXT: $x14_x15 = PADD_DW $x0_pair, $x0_pair
     ; RV32_P-NEXT: SD_RV32 $x14_x15, killed renamable $x10, 0 :: (store (s64) into %ir.a)
     ; RV32_P-NEXT: SD_RV32 $x14_x15, killed renamable $x11, 0 :: (store (s64) into %ir.b)
     ; RV32_P-NEXT: SD_RV32 $x14_x15, killed renamable $x12, 0 :: (store (s64) into %ir.c)