[X86] Teach X86SelectionDAGInfo::EmitTargetCodeForMemcpy about GNUX32

Summary:
In GNUX23, is64BitMode returns true, but pointers are 32-bits. So we shouldn't copy pointer values into RSI/RDI since the widths don't match.

Fixes PR38865 despite what the title says. I think the llvm_unreachable in the copyPhysReg code tricked the optimizer and made the fatal error trigger.

Reviewers: rnk, efriedma, MatzeB, echristo

Reviewed By: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D51893

llvm-svn: 342015

1 files changed, 47 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/X86/pr38865.ll b/llvm/test/CodeGen/X86/pr38865.ll
new file mode 100644
index 00000000000..5c8689203c7
--- /dev/null
+++ b/llvm/test/CodeGen/X86/pr38865.ll
@@ -0,0 +1,47 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -show-mc-encoding < %s | FileCheck %s
+
+target datalayout = "e-m:e-p:32:32-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnux32"
+
+%struct.a = type { [65 x i32] }
+
+@c = global %struct.a zeroinitializer, align 4
+
+define void @e() nounwind {
+; CHECK-LABEL: e:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    pushq %rbx # encoding: [0x53]
+; CHECK-NEXT:    subl $528, %esp # encoding: [0x81,0xec,0x10,0x02,0x00,0x00]
+; CHECK-NEXT:    # imm = 0x210
+; CHECK-NEXT:    leal {{[0-9]+}}(%rsp), %ebx # encoding: [0x8d,0x9c,0x24,0x08,0x01,0x00,0x00]
+; CHECK-NEXT:    movl $c, %esi # encoding: [0xbe,A,A,A,A]
+; CHECK-NEXT:    # fixup A - offset: 1, value: c, kind: FK_Data_4
+; CHECK-NEXT:    movl $260, %edx # encoding: [0xba,0x04,0x01,0x00,0x00]
+; CHECK-NEXT:    # imm = 0x104
+; CHECK-NEXT:    movl %ebx, %edi # encoding: [0x89,0xdf]
+; CHECK-NEXT:    callq memcpy # encoding: [0xe8,A,A,A,A]
+; CHECK-NEXT:    # fixup A - offset: 1, value: memcpy-4, kind: FK_PCRel_4
+; CHECK-NEXT:    movl $32, %ecx # encoding: [0xb9,0x20,0x00,0x00,0x00]
+; CHECK-NEXT:    movl %esp, %edi # encoding: [0x89,0xe7]
+; CHECK-NEXT:    movl %ebx, %esi # encoding: [0x89,0xde]
+; CHECK-NEXT:    rep;movsq (%esi), %es:(%edi) # encoding: [0xf3,0x67,0x48,0xa5]
+; CHECK-NEXT:    movl {{[0-9]+}}(%esp), %eax # encoding: [0x67,0x8b,0x84,0x24,0x08,0x02,0x00,0x00]
+; CHECK-NEXT:    movl %eax, {{[0-9]+}}(%esp) # encoding: [0x67,0x89,0x84,0x24,0x00,0x01,0x00,0x00]
+; CHECK-NEXT:    callq d # encoding: [0xe8,A,A,A,A]
+; CHECK-NEXT:    # fixup A - offset: 1, value: d-4, kind: FK_PCRel_4
+; CHECK-NEXT:    addl $528, %esp # encoding: [0x81,0xc4,0x10,0x02,0x00,0x00]
+; CHECK-NEXT:    # imm = 0x210
+; CHECK-NEXT:    popq %rbx # encoding: [0x5b]
+; CHECK-NEXT:    retq # encoding: [0xc3]
+entry:
+  %byval-temp = alloca %struct.a, align 8
+  %0 = bitcast %struct.a* %byval-temp to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* nonnull align 8 %0, i8* align 4 bitcast (%struct.a* @c to i8*), i32 260, i1 false)
+  call void @d(%struct.a* byval nonnull align 8 %byval-temp)
+  ret void
+}
+
+declare void @d(%struct.a* byval align 8) local_unnamed_addr #1
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture writeonly, i8* nocapture readonly, i32, i1)