[llvm] [AArch64] Guard against non-simple types in udiv sve costs. (PR #148580)

Mon Jul 14 01:05:45 PDT 2025

llvmbot wrote:




@llvm/pr-subscribers-llvm-analysis

Author: David Green (davemgreen)

<details>
<summary>Changes</summary>

The code here probably needs to change to handle types more uniformly, but this prevents it from trying to use a simple type where it does not exist.

Fixes #148438.

---
Full diff: https://github.com/llvm/llvm-project/pull/148580.diff


2 Files Affected:

- (modified) llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp (+4-4) 
- (modified) llvm/test/Analysis/CostModel/AArch64/sve-div.ll (+8) 


``````````diff

diff --git a/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
index 392f1f6efa997..796a53e9f29cc 100644
--- a/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
@@ -4126,10 +4126,10 @@ InstructionCost AArch64TTIImpl::getArithmeticInstrCost(
       if (TLI->isOperationLegalOrCustom(ISD, LT.second) && ST->hasSVE()) {
         // SDIV/UDIV operations are lowered using SVE, then we can have less
         // costs.
-        if (isa<FixedVectorType>(Ty) && cast<FixedVectorType>(Ty)
-                                                ->getPrimitiveSizeInBits()
-                                                .getFixedValue() < 128) {
-          EVT VT = TLI->getValueType(DL, Ty);
+        if (VT.isSimple() && isa<FixedVectorType>(Ty) &&
+            cast<FixedVectorType>(Ty)
+                    ->getPrimitiveSizeInBits()
+                    .getFixedValue() < 128) {
           static const CostTblEntry DivTbl[]{
               {ISD::SDIV, MVT::v2i8, 5},  {ISD::SDIV, MVT::v4i8, 8},
               {ISD::SDIV, MVT::v8i8, 8},  {ISD::SDIV, MVT::v2i16, 5},
diff --git a/llvm/test/Analysis/CostModel/AArch64/sve-div.ll b/llvm/test/Analysis/CostModel/AArch64/sve-div.ll
index c055d3218f65b..84a9ca0fab6d8 100644
--- a/llvm/test/Analysis/CostModel/AArch64/sve-div.ll
+++ b/llvm/test/Analysis/CostModel/AArch64/sve-div.ll
@@ -10,6 +10,7 @@ define void @sdiv() {
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V8i64 = sdiv <8 x i64> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:1 CodeSize:4 Lat:4 SizeLat:4 for: %V2i32 = sdiv <2 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:2 CodeSize:4 Lat:4 SizeLat:4 for: %V4i32 = sdiv <4 x i32> undef, undef
+; CHECK-NEXT:  Cost Model: Found costs of 4 for: %V6i32 = sdiv <6 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of 4 for: %V8i32 = sdiv <8 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V16i32 = sdiv <16 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:5 CodeSize:4 Lat:4 SizeLat:4 for: %V2i16 = sdiv <2 x i16> undef, undef
@@ -19,6 +20,7 @@ define void @sdiv() {
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:32 CodeSize:4 Lat:4 SizeLat:4 for: %V32i16 = sdiv <32 x i16> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:5 CodeSize:4 Lat:4 SizeLat:4 for: %V2i8 = sdiv <2 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V4i8 = sdiv <4 x i8> undef, undef
+; CHECK-NEXT:  Cost Model: Found costs of RThru:16 CodeSize:4 Lat:4 SizeLat:4 for: %V6i8 = sdiv <6 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V8i8 = sdiv <8 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:16 CodeSize:4 Lat:4 SizeLat:4 for: %V16i8 = sdiv <16 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:32 CodeSize:4 Lat:4 SizeLat:4 for: %V32i8 = sdiv <32 x i8> undef, undef
@@ -48,6 +50,7 @@ define void @sdiv() {
   %V8i64 = sdiv <8 x i64> undef, undef
   %V2i32 = sdiv <2 x i32> undef, undef
   %V4i32 = sdiv <4 x i32> undef, undef
+  %V6i32 = sdiv <6 x i32> undef, undef
   %V8i32 = sdiv <8 x i32> undef, undef
   %V16i32 = sdiv <16 x i32> undef, undef
   %V2i16 = sdiv <2 x i16> undef, undef
@@ -57,6 +60,7 @@ define void @sdiv() {
   %V32i16 = sdiv <32 x i16> undef, undef
   %V2i8 = sdiv <2 x i8> undef, undef
   %V4i8 = sdiv <4 x i8> undef, undef
+  %V6i8 = sdiv <6 x i8> undef, undef
   %V8i8 = sdiv <8 x i8> undef, undef
   %V16i8 = sdiv <16 x i8> undef, undef
   %V32i8 = sdiv <32 x i8> undef, undef
@@ -89,6 +93,7 @@ define void @udiv() {
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V8i64 = udiv <8 x i64> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:1 CodeSize:4 Lat:4 SizeLat:4 for: %V2i32 = udiv <2 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:2 CodeSize:4 Lat:4 SizeLat:4 for: %V4i32 = udiv <4 x i32> undef, undef
+; CHECK-NEXT:  Cost Model: Found costs of 4 for: %V6i32 = udiv <6 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of 4 for: %V8i32 = udiv <8 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V16i32 = udiv <16 x i32> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:5 CodeSize:4 Lat:4 SizeLat:4 for: %V2i16 = udiv <2 x i16> undef, undef
@@ -98,6 +103,7 @@ define void @udiv() {
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:32 CodeSize:4 Lat:4 SizeLat:4 for: %V32i16 = udiv <32 x i16> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:5 CodeSize:4 Lat:4 SizeLat:4 for: %V2i8 = udiv <2 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V4i8 = udiv <4 x i8> undef, undef
+; CHECK-NEXT:  Cost Model: Found costs of RThru:16 CodeSize:4 Lat:4 SizeLat:4 for: %V6i8 = udiv <6 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:8 CodeSize:4 Lat:4 SizeLat:4 for: %V8i8 = udiv <8 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:16 CodeSize:4 Lat:4 SizeLat:4 for: %V16i8 = udiv <16 x i8> undef, undef
 ; CHECK-NEXT:  Cost Model: Found costs of RThru:32 CodeSize:4 Lat:4 SizeLat:4 for: %V32i8 = udiv <32 x i8> undef, undef
@@ -127,6 +133,7 @@ define void @udiv() {
   %V8i64 = udiv <8 x i64> undef, undef
   %V2i32 = udiv <2 x i32> undef, undef
   %V4i32 = udiv <4 x i32> undef, undef
+  %V6i32 = udiv <6 x i32> undef, undef
   %V8i32 = udiv <8 x i32> undef, undef
   %V16i32 = udiv <16 x i32> undef, undef
   %V2i16 = udiv <2 x i16> undef, undef
@@ -136,6 +143,7 @@ define void @udiv() {
   %V32i16 = udiv <32 x i16> undef, undef
   %V2i8 = udiv <2 x i8> undef, undef
   %V4i8 = udiv <4 x i8> undef, undef
+  %V6i8 = udiv <6 x i8> undef, undef
   %V8i8 = udiv <8 x i8> undef, undef
   %V16i8 = udiv <16 x i8> undef, undef
   %V32i8 = udiv <32 x i8> undef, undef

``````````

</details>


https://github.com/llvm/llvm-project/pull/148580
