[GISel][Inlineasm] Support inlineasm i/s constraint for symbols (#170094)

Author: KRM7

llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp

@@ -657,7 +657,18 @@ bool InlineAsmLowering::lowerAsmOperandForConstraint(
   switch (ConstraintLetter) {
   default:
     return false;
+  case 's': // Integer immediate not known at compile time
+    if (const auto *GV = dyn_cast<GlobalValue>(Val)) {
+      Ops.push_back(MachineOperand::CreateGA(GV, /*Offset=*/0));
+      return true;
+    }
+    return false;
   case 'i': // Simple Integer or Relocatable Constant
+    if (const auto *GV = dyn_cast<GlobalValue>(Val)) {
+      Ops.push_back(MachineOperand::CreateGA(GV, /*Offset=*/0));
+      return true;
+    }
+    [[fallthrough]];
   case 'n': // immediate integer with a known value.
     if (ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
       assert(CI->getBitWidth() <= 64 &&

llvm/test/CodeGen/AArch64/GlobalISel/irtranslator-inline-asm.ll

@@ -183,6 +183,25 @@ define void @test_input_imm() {
   ret void
 }
 
+@var = global i64 0, align 8
+define void @test_immediate_constraint_sym() {
+  ; CHECK-LABEL: name: test_immediate_constraint_sym
+  ; CHECK: bb.1 (%ir-block.0):
+  ; CHECK-NEXT:   INLINEASM &"#TEST $0", 9 /* sideeffect mayload attdialect */, 13 /* imm */, @var
+  ; CHECK-NEXT:   RET_ReallyLR
+  call void asm sideeffect "#TEST $0", "i"(ptr @var)
+  ret void
+}
+
+define void @test_s_constraint() {
+  ; CHECK-LABEL: name: test_s_constraint
+  ; CHECK: bb.1 (%ir-block.0):
+  ; CHECK-NEXT:   INLINEASM &"#TEST $0", 9 /* sideeffect mayload attdialect */, 13 /* imm */, @var
+  ; CHECK-NEXT:   RET_ReallyLR
+  call void asm sideeffect "#TEST $0", "s"(ptr @var)
+  ret void
+}
+
 define zeroext i8 @test_input_register(ptr %src) nounwind {
   ; CHECK-LABEL: name: test_input_register
   ; CHECK: bb.1.entry: