fix runOnImplicitGEP for more than 1 index missing (google#1254)

Since runOnGEPFromGEP has been supported more cases, the if statement
removed by this commit is not needed. In fact, removing it fix code as
shown in the test here added.

Fix google#1225

lib/SimplifyPointerBitcastPass.cpp

@@ -460,11 +460,9 @@ bool clspv::SimplifyPointerBitcastPass::runOnImplicitGEP(Module &M) const {
           auto *gep = dyn_cast<GetElementPtrInst>(&I);
           auto *call = dyn_cast_or_null<CallInst>(&I);
           bool userCall = call && !call->getCalledFunction()->isDeclaration();
-          if ((Steps > 0 && !gep) || (Steps == 1)) {
-            if (!userCall && (gep || PerfectMatch)) {
-              GEPAliasingList.push_back(
-                  {&I, Steps, PerfectMatch ? nullptr : gep});
-            }
+          if (!userCall && (gep || PerfectMatch)) {
+            GEPAliasingList.push_back(
+                {&I, Steps, PerfectMatch ? nullptr : gep});
           }
         } else if (isa<StoreInst>(&I) && !isa<GetElementPtrInst>(source)) {
           GEPBeforeStoreList.push_back({&I, dest_ty});

test/PointerCasts/issue-1225.ll

@@ -0,0 +1,18 @@
+; RUN: clspv-opt %s -o %t.ll --passes=simplify-pointer-bitcast,replace-pointer-bitcast
+; RUN: FileCheck %s < %t.ll
+
+; CHECK: [[gep:%[^ ]+]] = getelementptr { %struct.s, %struct.s }, ptr %alloca, i32 0, i32 0, i32 0, i32 1
+; CHECK: load i64, ptr [[gep]], align 8
+
+target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024"
+target triple = "spir64-unknown-unknown"
+
+%struct.s = type { [8 x i64], i32 }
+
+define spir_kernel void @foo() {
+entry:
+  %alloca = alloca { %struct.s, %struct.s }, align 8
+  %gep = getelementptr inbounds [8 x i64], ptr %alloca, i64 0, i64 1
+  %load = load i64, ptr %gep, align 8
+  ret void
+}