Author: Julien Jorge Date: 2020-12-01T13:56:00-08:00 New Revision: 8b89bc0de0e190be04991a9622c5866a2e93ef6d
URL: https://github.com/llvm/llvm-project/commit/8b89bc0de0e190be04991a9622c5866a2e93ef6d DIFF: https://github.com/llvm/llvm-project/commit/8b89bc0de0e190be04991a9622c5866a2e93ef6d.diff LOG: [WebAssembly] Don't fold frame offset for global addresses When machine instructions are in the form of ``` %0 = CONST_I32 @str %1 = ADD_I32 %stack.0, %0 %2 = LOAD 0, 0, %1 ``` In the `ADD_I32` instruction, it is possible to fold it if `%0` is a `CONST_I32` from an immediate number. But in this case it is a global address, so we shouldn't do that. But we haven't checked if the operand of `ADD` is an immediate so far. This fixes the problem. (The case applies the same for `ADD_I64` and `CONST_I64` instructions.) Fixes https://bugs.llvm.org/show_bug.cgi?id=47944. Patch by Julien Jorge (jjo...@quarkslab.com) Reviewed By: dschuff Differential Revision: https://reviews.llvm.org/D90577 (cherry picked from commit 0fca6517118d435f9c2d7afe6135fd5f357509b5) Added: Modified: llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp llvm/test/CodeGen/WebAssembly/userstack.ll Removed: ################################################################################ diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td index 5ff0d73534a6..085910f01ee6 100644 --- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td +++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td @@ -328,7 +328,9 @@ defm CONST_F64 : I<(outs F64:$res), (ins f64imm_op:$imm), } // isMoveImm = 1, isAsCheapAsAMove = 1, isReMaterializable = 1 def : Pat<(i32 (WebAssemblywrapper tglobaladdr:$addr)), - (CONST_I32 tglobaladdr:$addr)>, Requires<[IsNotPIC]>; + (CONST_I32 tglobaladdr:$addr)>, Requires<[IsNotPIC, HasAddr32]>; +def : Pat<(i64 (WebAssemblywrapper tglobaladdr:$addr)), + (CONST_I64 tglobaladdr:$addr)>, Requires<[IsNotPIC, HasAddr64]>; def : Pat<(i32 (WebAssemblywrapper tglobaladdr:$addr)), (GLOBAL_GET_I32 tglobaladdr:$addr)>, Requires<[IsPIC]>; diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp index 130589c9df8c..6b6394a58339 100644 --- a/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp +++ b/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp @@ -101,10 +101,12 @@ void WebAssemblyRegisterInfo::eliminateFrameIndex( WebAssemblyFrameLowering::getOpcConst(MF) && MRI.hasOneNonDBGUse(Def->getOperand(0).getReg())) { MachineOperand &ImmMO = Def->getOperand(1); - ImmMO.setImm(ImmMO.getImm() + uint32_t(FrameOffset)); - MI.getOperand(FIOperandNum) - .ChangeToRegister(FrameRegister, /*isDef=*/false); - return; + if (ImmMO.isImm()) { + ImmMO.setImm(ImmMO.getImm() + uint32_t(FrameOffset)); + MI.getOperand(FIOperandNum) + .ChangeToRegister(FrameRegister, /*isDef=*/false); + return; + } } } } diff --git a/llvm/test/CodeGen/WebAssembly/userstack.ll b/llvm/test/CodeGen/WebAssembly/userstack.ll index dec202ea6af9..3d0e0d8c86a0 100644 --- a/llvm/test/CodeGen/WebAssembly/userstack.ll +++ b/llvm/test/CodeGen/WebAssembly/userstack.ll @@ -328,6 +328,22 @@ define void @inline_asm() { ret void } +; We optimize the format of "frame offset + operand" by folding it, but this is +; only possible when that operand is an immediate. In this example it is a +; global address, so we should not fold it. +; CHECK-LABEL: frame_offset_with_global_address +; CHECK: i[[PTR]].const ${{.*}}=, str +@str = local_unnamed_addr global [3 x i8] c"abc", align 16 +define i8 @frame_offset_with_global_address() { + %1 = alloca i8, align 4 + %2 = ptrtoint i8* %1 to i32 + ;; Here @str is a global address and not an immediate, so cannot be folded + %3 = getelementptr [3 x i8], [3 x i8]* @str, i32 0, i32 %2 + %4 = load i8, i8* %3, align 8 + %5 = and i8 %4, 67 + ret i8 %5 +} + ; CHECK: .globaltype __stack_pointer, i[[PTR]]{{$}} ; TODO: test over-aligned alloca _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
