[WebAssembly] Fold TargetGlobalAddress with added offset (#145829)
Previously we only folded TargetGlobalAddresses into the memarg if they
were on their own, so this patch supports folding TargetGlobalAddresses
that are added to some other offset.
Previously we weren't able to do this because we didn't have nuw on the
add, but we can now that getelementptr has nuw and is plumbed through to
the add in 0564d0665b302d1c7861e03d2995612f46613a0f.
Fixes #61930
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyISelDAGToDAG.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyISelDAGToDAG.cpp
index 48c0b7e..ac819cf 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyISelDAGToDAG.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyISelDAGToDAG.cpp
@@ -343,17 +343,29 @@
if (N.getOpcode() == ISD::ADD && !N.getNode()->getFlags().hasNoUnsignedWrap())
return false;
- // Folds constants in an add into the offset.
for (size_t i = 0; i < 2; ++i) {
SDValue Op = N.getOperand(i);
SDValue OtherOp = N.getOperand(i == 0 ? 1 : 0);
+ // Folds constants in an add into the offset.
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Op)) {
Offset =
CurDAG->getTargetConstant(CN->getZExtValue(), SDLoc(N), OffsetType);
Addr = OtherOp;
return true;
}
+
+ // Fold target global addresses into the offset.
+ if (!TM.isPositionIndependent()) {
+ if (Op.getOpcode() == WebAssemblyISD::Wrapper)
+ Op = Op.getOperand(0);
+
+ if (Op.getOpcode() == ISD::TargetGlobalAddress) {
+ Addr = OtherOp;
+ Offset = Op;
+ return true;
+ }
+ }
}
return false;
}
diff --git a/llvm/test/CodeGen/WebAssembly/eh-lsda.ll b/llvm/test/CodeGen/WebAssembly/eh-lsda.ll
index ce55f76..d5b28b2 100644
--- a/llvm/test/CodeGen/WebAssembly/eh-lsda.ll
+++ b/llvm/test/CodeGen/WebAssembly/eh-lsda.ll
@@ -66,9 +66,9 @@
; CHECK-LABEL: test1:
; In static linking, we load GCC_except_table as a constant directly.
-; NOPIC: i[[PTR]].const $push[[CONTEXT:.*]]=, __wasm_lpad_context
+; NOPIC: i[[PTR]].const $push[[CONTEXT:.*]]=, {{[48]}}
; NOPIC-NEXT: i[[PTR]].const $push[[EXCEPT_TABLE:.*]]=, GCC_except_table1
-; NOPIC-NEXT: i[[PTR]].store {{[48]}}($pop[[CONTEXT]]), $pop[[EXCEPT_TABLE]]
+; NOPIC-NEXT: i[[PTR]].store __wasm_lpad_context($pop[[CONTEXT]]), $pop[[EXCEPT_TABLE]]
; In case of PIC, we make GCC_except_table symbols a relative on based on
; __memory_base.
diff --git a/llvm/test/CodeGen/WebAssembly/exception-legacy.ll b/llvm/test/CodeGen/WebAssembly/exception-legacy.ll
index b4ffd18..149e443 100644
--- a/llvm/test/CodeGen/WebAssembly/exception-legacy.ll
+++ b/llvm/test/CodeGen/WebAssembly/exception-legacy.ll
@@ -34,7 +34,7 @@
; CHECK: call foo
; CHECK: catch $[[EXN:[0-9]+]]=, __cpp_exception
; CHECK: global.set __stack_pointer
-; CHECK: i32.{{store|const}} {{.*}} __wasm_lpad_context
+; CHECK: i32.store __wasm_lpad_context
; CHECK: call $drop=, _Unwind_CallPersonality, $[[EXN]]
; CHECK: block
; CHECK: br_if 0
diff --git a/llvm/test/CodeGen/WebAssembly/offset.ll b/llvm/test/CodeGen/WebAssembly/offset.ll
index 1305084..109607c 100644
--- a/llvm/test/CodeGen/WebAssembly/offset.ll
+++ b/llvm/test/CodeGen/WebAssembly/offset.ll
@@ -118,6 +118,16 @@
ret i32 %t
}
+define i32 @load_i32_global_with_folded_gep_offset_nonconst_nuw(i32 %idx) {
+; CHECK-LABEL: load_i32_global_with_folded_gep_offset_nonconst_nuw:
+; CHECK: i32.const $push0=, 2
+; CHECK: i32.shl $push1=, $0, $pop0
+; CHECK: i32.load $push2=, gv($pop1)
+ %s = getelementptr nuw i32, ptr @gv, i32 %idx
+ %t = load i32, ptr %s
+ ret i32 %t
+}
+
;===----------------------------------------------------------------------------
; Loads: 64-bit
;===----------------------------------------------------------------------------
