[SelectionDAG] Move SelectionDAG::getAllOnesConstant out of line. NFC

[topperc]

This function has to get the scalar size and create an APInt. I don't think it belongs inline.

[llvmbot]

@llvm/pr-subscribers-llvm-selectiondag

Author: Craig Topper (topperc)

Changes

This function has to get the scalar size and create an APInt. I don't think it belongs inline.

---

Full diff: https://github.com/llvm/llvm-project/pull/102995.diff

2 Files Affected:

• (modified) llvm/include/llvm/CodeGen/SelectionDAG.h (+1-4)
• (modified) llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp (+6)

diff --git a/llvm/include/llvm/CodeGen/SelectionDAG.h b/llvm/include/llvm/CodeGen/SelectionDAG.h
index 1d0124ec755352..9ce3c48a7f76cb 100644
--- a/llvm/include/llvm/CodeGen/SelectionDAG.h
+++ b/llvm/include/llvm/CodeGen/SelectionDAG.h
@@ -675,10 +675,7 @@ class SelectionDAG {
                       bool isTarget = false, bool isOpaque = false);
 
   SDValue getAllOnesConstant(const SDLoc &DL, EVT VT, bool IsTarget = false,
-                             bool IsOpaque = false) {
-    return getConstant(APInt::getAllOnes(VT.getScalarSizeInBits()), DL, VT,
-                       IsTarget, IsOpaque);
-  }
+                             bool IsOpaque = false);
 
   SDValue getConstant(const ConstantInt &Val, const SDLoc &DL, EVT VT,
                       bool isTarget = false, bool isOpaque = false);
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index c3a7df5361cd45..fcf28f00a1008e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1748,6 +1748,12 @@ SDValue SelectionDAG::getConstant(const ConstantInt &Val, const SDLoc &DL,
   return Result;
 }
 
+SDValue SelectionDAG::getAllOnesConstant(const SDLoc &DL, EVT VT,
+                                         bool IsTarget, bool IsOpaque) {
+  return getConstant(APInt::getAllOnes(VT.getScalarSizeInBits()), DL, VT,
+                     IsTarget, IsOpaque);
+}
+
 SDValue SelectionDAG::getIntPtrConstant(uint64_t Val, const SDLoc &DL,
                                         bool isTarget) {
   return getConstant(Val, DL, TLI->getPointerTy(getDataLayout()), isTarget);

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[arsenm]

Can't this just use -1 and let the implementation extend to APInt if it's larger?

[nikic]

Doing that is exactly how most i128 miscompiles get introduced ;) Note that getConstant() performs a zero extension, not a sign extension.

[arsenm]

But that sounds like a bug, generally constants are sign extended in other contexts in llvm (e.g. in MachineOperand)

[nikic]

No, constants in LLVM are zero extended by default. They only get sign extended to 64 bit as a result of normal integer promotion rules. Some APIs have a flag to switch to sign extension instead, and everyone always forgets to set it when necessary, because things look like they work correctly for small integer types. (See also #80309.)

[nikic]

LGTM

[RKSimon]

LGTM