[llvm] 1e0f480 - [AArch64][GlobalISel] Use a integer type for extract narrowing. (#216254)

[via llvm-commits]

Author: David Green
Date: 2026-08-22T06:52:15Z
New Revision: 1e0f4802e0e3865e51a82ca29b49cb722510379e

URL: https://github.com/llvm/llvm-project/commit/1e0f4802e0e3865e51a82ca29b49cb722510379e
DIFF: https://github.com/llvm/llvm-project/commit/1e0f4802e0e3865e51a82ca29b49cb722510379e.diff

LOG: [AArch64][GlobalISel] Use a integer type for extract narrowing. (#216254)

Added: 
    

Modified: 
    llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
    llvm/test/CodeGen/AArch64/GlobalISel/legalize-extracts.mir
    llvm/unittests/CodeGen/GlobalISel/LegalizerHelperTest.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 6f85390fd4ede..0d7d19ce23762 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -7537,7 +7537,7 @@ LegalizerHelper::narrowScalarExtract(MachineInstr &MI, unsigned TypeIdx,
     Register SegReg = SrcRegs[i];
     if (ExtractOffset != 0 || SegSize != NarrowSize) {
       // A genuine extract is needed.
-      SegReg = MRI.createGenericVirtualRegister(LLT::scalar(SegSize));
+      SegReg = MRI.createGenericVirtualRegister(LLT::integer(SegSize));
       MIRBuilder.buildExtract(SegReg, SrcRegs[i], ExtractOffset);
     }
 

diff  --git a/llvm/test/CodeGen/AArch64/GlobalISel/legalize-extracts.mir b/llvm/test/CodeGen/AArch64/GlobalISel/legalize-extracts.mir
index 4c07318cd582d..2b15463685191 100644
--- a/llvm/test/CodeGen/AArch64/GlobalISel/legalize-extracts.mir
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/legalize-extracts.mir
@@ -348,8 +348,8 @@ body: |
     ; CHECK-NEXT: {{  $}}
     ; CHECK-NEXT: %h0:_(i16) = COPY $h0
     ; CHECK-NEXT: [[MV:%[0-9]+]]:_(i64) = G_MERGE_VALUES %h0(i16), %h0(i16), %h0(i16), %h0(i16)
-    ; CHECK-NEXT: [[EXTRACT:%[0-9]+]]:_(s16) = G_EXTRACT [[MV]](i64), 1
-    ; CHECK-NEXT: %extract:_(i16) = COPY [[EXTRACT]](s16)
+    ; CHECK-NEXT: [[EXTRACT:%[0-9]+]]:_(i16) = G_EXTRACT [[MV]](i64), 1
+    ; CHECK-NEXT: %extract:_(i16) = COPY [[EXTRACT]](i16)
     ; CHECK-NEXT: $h0 = COPY %extract(i16)
     ; CHECK-NEXT: RET_ReallyLR implicit $h0
     %h0:_(i16) = COPY $h0
@@ -369,8 +369,8 @@ body: |
     ; CHECK-NEXT: {{  $}}
     ; CHECK-NEXT: %h0:_(i16) = COPY $h0
     ; CHECK-NEXT: [[MV:%[0-9]+]]:_(i64) = G_MERGE_VALUES %h0(i16), %h0(i16), %h0(i16), %h0(i16)
-    ; CHECK-NEXT: [[EXTRACT:%[0-9]+]]:_(s32) = G_EXTRACT [[MV]](i64), 1
-    ; CHECK-NEXT: %extract:_(i32) = COPY [[EXTRACT]](s32)
+    ; CHECK-NEXT: [[EXTRACT:%[0-9]+]]:_(i32) = G_EXTRACT [[MV]](i64), 1
+    ; CHECK-NEXT: %extract:_(i32) = COPY [[EXTRACT]](i32)
     ; CHECK-NEXT: $w0 = COPY %extract(i32)
     ; CHECK-NEXT: RET_ReallyLR implicit $w0
     %h0:_(i16) = COPY $h0

diff  --git a/llvm/unittests/CodeGen/GlobalISel/LegalizerHelperTest.cpp b/llvm/unittests/CodeGen/GlobalISel/LegalizerHelperTest.cpp
index 346f3d9a88390..7201a9a480355 100644
--- a/llvm/unittests/CodeGen/GlobalISel/LegalizerHelperTest.cpp
+++ b/llvm/unittests/CodeGen/GlobalISel/LegalizerHelperTest.cpp
@@ -3228,7 +3228,7 @@ TEST_F(AArch64GISelMITest, NarrowScalarExtract) {
   CHECK: [[UV:%[0-9]+]]:_(i32), [[UV1:%[0-9]+]]:_(i32) = G_UNMERGE_VALUES
   CHECK: [[COPY:%[0-9]+]]:_(i32) = COPY [[UV1]]
   CHECK: [[UV3:%[0-9]+]]:_(i32), [[UV4:%[0-9]+]]:_(i32) = G_UNMERGE_VALUES
-  CHECK: [[EXTR:%[0-9]+]]:_(s16) = G_EXTRACT [[UV3]]:_(i32), 0
+  CHECK: [[EXTR:%[0-9]+]]:_(i16) = G_EXTRACT [[UV3]]:_(i32), 0
   CHECK: [[COPY:%[0-9]+]]:_(i16) = COPY [[EXTR]]
   )";