Fix issue #3802 - Fix size_t size for 32bit ABI on 64bit architectures.

driver/main.cpp

@@ -728,6 +728,8 @@ void registerPredefinedTargetVersions() {
   // Set versions for arch bitwidth
   if (gDataLayout->getPointerSizeInBits() == 64) {
     VersionCondition::addPredefinedGlobalIdent("D_LP64");
+  } else if (triple.isArch64Bit()) {
+    VersionCondition::addPredefinedGlobalIdent("D_X32");
   } else if (triple.isArch16Bit()) {
     VersionCondition::addPredefinedGlobalIdent("D_P16");
   }

gen/passes/SimplifyDRuntimeCalls.cpp

@@ -210,16 +210,16 @@ struct LLVM_LIBRARY_VISIBILITY AllocationOpt : public LibCallOptimization {
 // This module will also be used in jit runtime
 // copy these function here to avoid dependencies on rest of compiler
 LLIntegerType *DtoSize_t(llvm::LLVMContext &context,
-                         const llvm::Triple &triple) {
+                         const llvm::DataLayout &DL) {
   // the type of size_t does not change once set
   static LLIntegerType *t = nullptr;
   if (t == nullptr) {
-
-    if (triple.isArch64Bit()) {
+    const auto ptrsize = DL.getPointerSize();
+    if (ptrsize == 8) {
       t = LLType::getInt64Ty(context);
-    } else if (triple.isArch32Bit()) {
+    } else if (ptrsize == 4) {
       t = LLType::getInt32Ty(context);
-    } else if (triple.isArch16Bit()) {
+    } else if (ptrsize == 2) {
       t = LLType::getInt16Ty(context);
     } else {
       llvm_unreachable("Unsupported size_t width");
@@ -229,9 +229,8 @@ LLIntegerType *DtoSize_t(llvm::LLVMContext &context,
 }
 
 llvm::ConstantInt *DtoConstSize_t(llvm::LLVMContext &context,
-                                  const llvm::Triple &targetTriple,
-                                  uint64_t i) {
-  return LLConstantInt::get(DtoSize_t(context, targetTriple), i, false);
+                                  const llvm::DataLayout &DL, uint64_t i) {
+  return LLConstantInt::get(DtoSize_t(context, DL), i, false);
 }
 
 /// ArraySliceCopyOpt - Turn slice copies into llvm.memcpy when safe
@@ -272,13 +271,11 @@ struct LLVM_LIBRARY_VISIBILITY ArraySliceCopyOpt : public LibCallOptimization {
 
     // Equal length and the pointers definitely don't alias, so it's safe to
     // replace the call with memcpy
-    auto Size =
-        Sz != llvm::MemoryLocation::UnknownSize
-            ? DtoConstSize_t(
-                  Callee->getContext(),
-                  llvm::Triple(Callee->getParent()->getTargetTriple()), Sz)
-            : B.CreateMul(DstLength, ElemSz);
-    return EmitMemCpy(CI->getOperand(0), CI->getOperand(2), Size, 1, B);
+    auto size = Sz != llvm::MemoryLocation::UnknownSize
+                    ? DtoConstSize_t(Callee->getContext(),
+                                     Callee->getParent()->getDataLayout(), Sz)
+                    : B.CreateMul(DstLength, ElemSz);
+    return EmitMemCpy(CI->getOperand(0), CI->getOperand(2), size, 1, B);
   }
 };
 

gen/target.cpp

@@ -90,7 +90,7 @@ void Target::_init(const Param &params) {
   classinfosize = 0; // unused
   maxStaticDataSize = std::numeric_limits<unsigned long long>::max();
 
-  c.longsize = triple.isArch64Bit() && !isMSVC ? 8 : 4;
+  c.longsize = (ptrsize == 8) && !isMSVC ? 8 : 4;
   c.long_doublesize = realsize;
   c.wchar_tsize = triple.isOSWindows() ? 2 : 4;
 

gen/tollvm.cpp

@@ -16,6 +16,7 @@
 #include "dmd/id.h"
 #include "dmd/init.h"
 #include "dmd/module.h"
+#include "dmd/target.h"
 #include "driver/cl_options.h"
 #include "gen/abi.h"
 #include "gen/arrays.h"
@@ -298,13 +299,11 @@ LLIntegerType *DtoSize_t() {
   // the type of size_t does not change once set
   static LLIntegerType *t = nullptr;
   if (t == nullptr) {
-    auto triple = global.params.targetTriple;
-
-    if (triple->isArch64Bit()) {
+    if (target.ptrsize == 8) {
       t = LLType::getInt64Ty(gIR->context());
-    } else if (triple->isArch32Bit()) {
+    } else if (target.ptrsize == 4) {
       t = LLType::getInt32Ty(gIR->context());
-    } else if (triple->isArch16Bit()) {
+    } else if (target.ptrsize == 2) {
       t = LLType::getInt16Ty(gIR->context());
     } else {
       llvm_unreachable("Unsupported size_t width");

tests/compilable/arch64bit_abi32bit_gh3802.d

@@ -0,0 +1,33 @@
+// Tests compilation for 64-bit architecture with 32-bit word size ABI.
+// Triple examples: mips64el-linux-gnuabin32, x86_64-linux-gnux32
+// Targeting x86 because that's the most widely available target in our CI/developer systems.
+
+// REQUIRES: target_X86
+// RUN: %ldc -mtriple=x86_64-linux-gnux32 -O -c %s
+
+static assert((void*).sizeof == 4);
+static assert(size_t.sizeof == 4);
+static assert(ptrdiff_t.sizeof == 4);
+
+version (D_LP64) static assert(0);
+version (D_X32) { /* expected */ } else static assert(0);
+
+bool equals(string lhs, string rhs)
+{
+    foreach (const i; 0 .. lhs.length) {}
+    return false;
+}
+
+// test _d_array_slice_copy optimization IR pass (requires -O)
+auto test_ArraySliceCopyOpt()
+{
+    static void copy(int[] a, int[] b)
+    {
+        a[] = b[];
+    }
+
+    int[2] a = [1, 2];
+    int[2] b = [3, 4];
+    copy(a, b);
+    return a;
+}