[IRTranslator] Don't hardcode GEP index type

When breaking up loads and stores of aggregates, the IRTranslator uses
LLT::scalar(64) for the index type of the G_GEP instructions that
compute the addresses. This is unnecessarily large for 32-bit targets.
Use the int ptr type provided by the DataLayout instead.

Note that we're already doing the right thing when translating
getelementptr instructions from the IR. This is just an oversight when
generating new ones while translating loads/stores.

Both x86 and AArch64 already have tests confirming that the old
behaviour is preserved for 64-bit targets.

Differential Revision: https://reviews.llvm.org/D61852

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360656 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/GlobalISel/IRTranslator.cpp b/lib/CodeGen/GlobalISel/IRTranslator.cpp
index ba56054..939a9a9 100644 (file)
--- a/lib/CodeGen/GlobalISel/IRTranslator.cpp
+++ b/lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -461,9 +461,12 @@ bool IRTranslator::translateLoad(const User &U, MachineIRBuilder &MIRBuilder) {
   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(LI);
   unsigned Base = getOrCreateVReg(*LI.getPointerOperand());
 
+  Type *OffsetIRTy = DL->getIntPtrType(LI.getPointerOperandType());
+  LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
+
   for (unsigned i = 0; i < Regs.size(); ++i) {
     unsigned Addr = 0;
-    MIRBuilder.materializeGEP(Addr, Base, LLT::scalar(64), Offsets[i] / 8);
+    MIRBuilder.materializeGEP(Addr, Base, OffsetTy, Offsets[i] / 8);
 
     MachinePointerInfo Ptr(LI.getPointerOperand(), Offsets[i] / 8);
     unsigned BaseAlign = getMemOpAlignment(LI);
@@ -490,9 +493,12 @@ bool IRTranslator::translateStore(const User &U, MachineIRBuilder &MIRBuilder) {
   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(*SI.getValueOperand());
   unsigned Base = getOrCreateVReg(*SI.getPointerOperand());
 
+  Type *OffsetIRTy = DL->getIntPtrType(SI.getPointerOperandType());
+  LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
+
   for (unsigned i = 0; i < Vals.size(); ++i) {
     unsigned Addr = 0;
-    MIRBuilder.materializeGEP(Addr, Base, LLT::scalar(64), Offsets[i] / 8);
+    MIRBuilder.materializeGEP(Addr, Base, OffsetTy, Offsets[i] / 8);
 
     MachinePointerInfo Ptr(SI.getPointerOperand(), Offsets[i] / 8);
     unsigned BaseAlign = getMemOpAlignment(SI);

diff --git a/test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll b/test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll
index 1756737..1d7ca32 100644 (file)
--- a/test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll
+++ b/test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll
@@ -544,3 +544,20 @@ define i32 @test_constantstruct_v2s32_s32_s32() {
   %elt = extractelement <2 x i32> %vec, i32 0
   ret i32 %elt
 }
+
+define void @test_load_store_struct({i32, i32} *%addr) {
+; Make sure the IRTranslator doesn't use an unnecessarily large GEP index type
+; when breaking up loads and stores of aggregates.
+; CHECK-LABEL: name: test_load_store_struct
+; CHECK: [[ADDR1:%[0-9]+]]:_(p0) = COPY $r0
+; CHECK-DAG: [[VAL1:%[0-9]+]]:_(s32) = G_LOAD [[ADDR1]](p0) :: (load 4 from %ir.addr)
+; CHECK-DAG: [[OFFSET:%[0-9]+]]:_(s32) = G_CONSTANT i32 4
+; CHECK-DAG: [[ADDR2:%[0-9]+]]:_(p0) = G_GEP [[ADDR1]], [[OFFSET]](s32)
+; CHECK-DAG: [[VAL2:%[0-9]+]]:_(s32) = G_LOAD [[ADDR2]](p0) :: (load 4 from %ir.addr + 4)
+; CHECK-DAG: G_STORE [[VAL1]](s32), [[ADDR1]](p0) :: (store 4 into %ir.addr)
+; CHECK-DAG: [[ADDR2:%[0-9]+]]:_(p0) = G_GEP [[ADDR1]], [[OFFSET]](s32)
+; CHECK-DAG: G_STORE [[VAL2]](s32), [[ADDR2]](p0) :: (store 4 into %ir.addr + 4)
+  %val = load {i32, i32}, {i32, i32} *%addr, align 4
+  store {i32, i32} %val, {i32, i32} *%addr, align 4
+  ret void
+}