[llvm] d407e6c - [RISCV] Add test to showcase miscompile from #79072

[Luke Lau via llvm-commits]

Author: Luke Lau
Date: 2024-01-26T20:25:05+07:00
New Revision: d407e6ca61a422f25841674d8f0b5ea0dbec85f8

URL: https://github.com/llvm/llvm-project/commit/d407e6ca61a422f25841674d8f0b5ea0dbec85f8
DIFF: https://github.com/llvm/llvm-project/commit/d407e6ca61a422f25841674d8f0b5ea0dbec85f8.diff

LOG: [RISCV] Add test to showcase miscompile from #79072

Added: 
    

Modified: 
    llvm/test/CodeGen/RISCV/rvv/fixed-vectors-shuffle-exact-vlen.ll

Removed: 
    


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diff  --git a/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-shuffle-exact-vlen.ll b/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-shuffle-exact-vlen.ll
index c8c08ab1a987b3c..b2b6e3b4414b1f6 100644
--- a/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-shuffle-exact-vlen.ll
+++ b/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-shuffle-exact-vlen.ll
@@ -138,8 +138,8 @@ define <4 x i64> @m2_splat_two_source(<4 x i64> %v1, <4 x i64> %v2) vscale_range
   ret <4 x i64> %res
 }
 
-define <4 x i64> @m2_splat_into_identity_two_source(<4 x i64> %v1, <4 x i64> %v2) vscale_range(2,2) {
-; CHECK-LABEL: m2_splat_into_identity_two_source:
+define <4 x i64> @m2_splat_into_identity_two_source_v2_hi(<4 x i64> %v1, <4 x i64> %v2) vscale_range(2,2) {
+; CHECK-LABEL: m2_splat_into_identity_two_source_v2_hi:
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    vsetivli zero, 2, e64, m1, ta, ma
 ; CHECK-NEXT:    vrgather.vi v10, v8, 0
@@ -149,6 +149,20 @@ define <4 x i64> @m2_splat_into_identity_two_source(<4 x i64> %v1, <4 x i64> %v2
   ret <4 x i64> %res
 }
 
+; FIXME: This is a miscompile, we're clobbering the lower reg group of %v2
+; (v10), and the vmv1r.v is moving from the wrong reg group (should be v10)
+define <4 x i64> @m2_splat_into_slide_two_source_v2_lo(<4 x i64> %v1, <4 x i64> %v2) vscale_range(2,2) {
+; CHECK-LABEL: m2_splat_into_slide_two_source_v2_lo:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    vsetivli zero, 2, e64, m1, ta, ma
+; CHECK-NEXT:    vrgather.vi v10, v8, 0
+; CHECK-NEXT:    vmv1r.v v11, v8
+; CHECK-NEXT:    vmv2r.v v8, v10
+; CHECK-NEXT:    ret
+  %res = shufflevector <4 x i64> %v1, <4 x i64> %v2, <4 x i32> <i32 0, i32 0, i32 4, i32 5>
+  ret <4 x i64> %res
+}
+
 define <4 x i64> @m2_splat_into_slide_two_source(<4 x i64> %v1, <4 x i64> %v2) vscale_range(2,2) {
 ; CHECK-LABEL: m2_splat_into_slide_two_source:
 ; CHECK:       # %bb.0: