Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 140 insertions, 0 deletions

diff --git a/xpcom/reflect/xptcall/md/unix/xptcinvoke_ppc64_linux.cpp b/xpcom/reflect/xptcall/md/unix/xptcinvoke_ppc64_linux.cpp
new file mode 100644
index 0000000000..f7673bb29d
--- /dev/null
+++ b/xpcom/reflect/xptcall/md/unix/xptcinvoke_ppc64_linux.cpp
@@ -0,0 +1,140 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Platform specific code to invoke XPCOM methods on native objects
+
+#include "xptcprivate.h"
+
+// The purpose of NS_InvokeByIndex() is to map a platform
+// independent call to the platform ABI. To do that,
+// NS_InvokeByIndex() has to determine the method to call via vtable
+// access. The parameters for the method are read from the
+// nsXPTCVariant* and prepared for the native ABI.
+//
+// Prior to POWER8, all 64-bit Power ISA systems used ELF v1 ABI, found
+// here:
+//   https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html
+// and in particular:
+//   https://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#FUNC-CALL
+// Little-endian ppc64le, however, uses ELF v2 ABI, which is here:
+//   http://openpowerfoundation.org/wp-content/uploads/resources/leabi/leabi-20170510.pdf
+// and in particular section 2.2, page 22. However, most big-endian ppc64
+// systems still use ELF v1, so this file should support both.
+
+// 7 integral parameters are passed in registers, not including |this|
+// (i.e., r3-r10, with r3 being |this|).
+const uint32_t GPR_COUNT = 7;
+
+// 13 floating point parameters are passed in registers, either single or
+// double precision (i.e., f1-f13).
+const uint32_t FPR_COUNT = 13;
+
+// Both ABIs use the same register assignment strategy, as per this
+// example from V1 ABI section 3.2.3 and V2 ABI section 2.2.3.2 [page 43]:
+//
+// typedef struct {
+//   int    a;
+//   double dd;
+// } sparm;
+// sparm   s, t;
+// int     c, d, e;
+// long double ld;
+// double  ff, gg, hh;
+//
+// x = func(c, ff, d, ld, s, gg, t, e, hh);
+//
+// Parameter     Register     Offset in parameter save area
+// c             r3           0-7    (not stored in parameter save area)
+// ff            f1           8-15   (not stored)
+// d             r5           16-23  (not stored)
+// ld            f2,f3        24-39  (not stored)
+// s             r8,r9        40-55  (not stored)
+// gg            f4           56-63  (not stored)
+// t             (none)       64-79  (stored in parameter save area)
+// e             (none)       80-87  (stored)
+// hh            f5           88-95  (not stored)
+//
+// i.e., each successive FPR usage skips a GPR, but not the other way around.
+
+extern "C" void invoke_copy_to_stack(uint64_t* gpregs, double* fpregs,
+                                     uint32_t paramCount, nsXPTCVariant* s,
+                                     uint64_t* d)
+{
+    uint32_t nr_gpr = 0u;
+    uint32_t nr_fpr = 0u;
+    uint64_t value = 0u;
+
+    for (uint32_t i = 0; i < paramCount; i++, s++) {
+        if (s->IsIndirect())
+            value = (uint64_t) &s->val;
+        else {
+            switch (s->type) {
+            case nsXPTType::T_FLOAT:                                break;
+            case nsXPTType::T_DOUBLE:                               break;
+            case nsXPTType::T_I8:     value = s->val.i8;            break;
+            case nsXPTType::T_I16:    value = s->val.i16;           break;
+            case nsXPTType::T_I32:    value = s->val.i32;           break;
+            case nsXPTType::T_I64:    value = s->val.i64;           break;
+            case nsXPTType::T_U8:     value = s->val.u8;            break;
+            case nsXPTType::T_U16:    value = s->val.u16;           break;
+            case nsXPTType::T_U32:    value = s->val.u32;           break;
+            case nsXPTType::T_U64:    value = s->val.u64;           break;
+            case nsXPTType::T_BOOL:   value = s->val.b;             break;
+            case nsXPTType::T_CHAR:   value = s->val.c;             break;
+            case nsXPTType::T_WCHAR:  value = s->val.wc;            break;
+            default:                  value = (uint64_t) s->val.p;  break;
+            }
+        }
+
+        if (!s->IsIndirect() && s->type == nsXPTType::T_DOUBLE) {
+            if (nr_fpr < FPR_COUNT) {
+                fpregs[nr_fpr++] = s->val.d;
+                // Even if we have enough FPRs, still skip space in
+                // the parameter area if we ran out of placeholder GPRs.
+                if (nr_gpr < GPR_COUNT) {
+                    nr_gpr++;
+                } else {
+                    d++;
+                }
+            } else {
+                *((double *)d) = s->val.d;
+                d++;
+            }
+        }
+        else if (!s->IsIndirect() && s->type == nsXPTType::T_FLOAT) {
+            if (nr_fpr < FPR_COUNT) {
+                // Single-precision floats are passed in FPRs too.
+                fpregs[nr_fpr++] = s->val.f;
+                if (nr_gpr < GPR_COUNT) {
+                    nr_gpr++;
+                } else {
+                    d++;
+                }
+            } else {
+#ifdef __LITTLE_ENDIAN__
+                *((float *)d) = s->val.f;
+#else
+                // Big endian needs adjustment to point to the least
+                // significant word.
+                float* p = (float*)d;
+                p++;
+                *p = s->val.f;
+#endif
+                d++;
+            }
+        }
+        else {
+            if (nr_gpr < GPR_COUNT) {
+                gpregs[nr_gpr++] = value;
+            } else {
+                *d++ = value;
+            }
+        }
+    }
+}
+
+EXPORT_XPCOM_API(nsresult)
+NS_InvokeByIndex(nsISupports* that, uint32_t methodIndex, uint32_t paramCount,
+                 nsXPTCVariant* params);