[llvm] 941f8a9 - [LV][NFC] Make ARM/mve-selectandorcost.ll test more robust (#197388)

[via llvm-commits]

Author: David Sherwood
Date: 2026-05-13T10:23:26+01:00
New Revision: 941f8a9ee61ae670e2bd905de86212ca7c40065c

URL: https://github.com/llvm/llvm-project/commit/941f8a9ee61ae670e2bd905de86212ca7c40065c
DIFF: https://github.com/llvm/llvm-project/commit/941f8a9ee61ae670e2bd905de86212ca7c40065c.diff

LOG: [LV][NFC] Make ARM/mve-selectandorcost.ll test more robust (#197388)

The test currently has an fdiv in the loop, which leads to vector costs
that are almost identical to the scalar cost. This makes the test
fragile and future cost model work for VPDerivedIVRecipe will cause the
test to favour the scalar version. I've changed the fdiv to fmul to make
the test more robust.

Added: 
    

Modified: 
    llvm/test/Transforms/LoopVectorize/ARM/mve-selectandorcost.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/LoopVectorize/ARM/mve-selectandorcost.ll b/llvm/test/Transforms/LoopVectorize/ARM/mve-selectandorcost.ll
index abc77b26d5053..917dae8ff2de1 100644
--- a/llvm/test/Transforms/LoopVectorize/ARM/mve-selectandorcost.ll
+++ b/llvm/test/Transforms/LoopVectorize/ARM/mve-selectandorcost.ll
@@ -43,7 +43,7 @@ define float @test(ptr nocapture readonly %pA, ptr nocapture readonly %pB, i32 %
 ; CHECK-NEXT:    [[TMP10:%.*]] = fadd fast <4 x float> [[TMP9]], [[TMP8]]
 ; CHECK-NEXT:    [[TMP11:%.*]] = fsub fast <4 x float> [[WIDE_LOAD]], [[WIDE_LOAD3]]
 ; CHECK-NEXT:    [[TMP12:%.*]] = call fast <4 x float> @llvm.fabs.v4f32(<4 x float> [[TMP11]])
-; CHECK-NEXT:    [[TMP13:%.*]] = fdiv fast <4 x float> [[TMP12]], [[TMP10]]
+; CHECK-NEXT:    [[TMP13:%.*]] = fmul fast <4 x float> [[TMP12]], [[TMP10]]
 ; CHECK-NEXT:    [[TMP14:%.*]] = select ninf <4 x i1> [[TMP7]], <4 x float> [[TMP13]], <4 x float> splat (float -0.000000e+00)
 ; CHECK-NEXT:    [[PREDPHI]] = fadd reassoc arcp contract afn <4 x float> [[VEC_PHI]], [[TMP14]]
 ; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 4
@@ -78,7 +78,7 @@ define float @test(ptr nocapture readonly %pA, ptr nocapture readonly %pB, i32 %
 ; CHECK-NEXT:    [[ADD:%.*]] = fadd fast float [[TMP20]], [[TMP19]]
 ; CHECK-NEXT:    [[SUB:%.*]] = fsub fast float [[TMP17]], [[TMP18]]
 ; CHECK-NEXT:    [[TMP21:%.*]] = tail call fast float @llvm.fabs.f32(float [[SUB]])
-; CHECK-NEXT:    [[DIV:%.*]] = fdiv fast float [[TMP21]], [[ADD]]
+; CHECK-NEXT:    [[DIV:%.*]] = fmul fast float [[TMP21]], [[ADD]]
 ; CHECK-NEXT:    [[ADD4:%.*]] = fadd fast float [[DIV]], [[ACCUM_017]]
 ; CHECK-NEXT:    br label %[[IF_END]]
 ; CHECK:       [[IF_END]]:
@@ -117,7 +117,7 @@ if.then:
   %add = fadd fast float %3, %2
   %sub = fsub fast float %0, %1
   %4 = tail call fast float @llvm.fabs.f32(float %sub)
-  %div = fdiv fast float %4, %add
+  %div = fmul fast float %4, %add
   %add4 = fadd fast float %div, %accum.017
   br label %if.end