auto merge of #14963 : w3ln4/rust/master, r=alexcrichton

The aim of these changes is not working out a generic bi-endianness architectures support but to allow people develop for little endian MIPS machines (issue #7190).

3 files changed, 171 insertions, 0 deletions

diff --git a/src/rt/arch/mipsel/_context.S b/src/rt/arch/mipsel/_context.S
new file mode 100644
index 00000000000..cfe77cc3045
--- /dev/null
+++ b/src/rt/arch/mipsel/_context.S
@@ -0,0 +1,88 @@
+// Mark stack as non-executable
+#if defined(__linux__) && defined(__ELF__)
+.section	.note.GNU-stack, "", @progbits
+#endif
+
+.text
+.globl rust_swap_registers
+.align 2
+.set nomips16
+.ent rust_swap_registers
+rust_swap_registers:
+        .set noreorder
+        .set nomacro
+        .set noat
+        sw $1, 1 * 4($4)
+        sw $2, 2 * 4($4)
+        sw $3, 3 * 4($4)
+        sw $4, 4 * 4($4)
+        sw $5, 5 * 4($4)
+        sw $6, 6 * 4($4)
+        sw $7, 7 * 4($4)
+
+        sw $8, 8 * 4($4)
+        sw $9, 9 * 4($4)
+        sw $10, 10 * 4($4)
+        sw $11, 11 * 4($4)
+        sw $12, 12 * 4($4)
+        sw $13, 13 * 4($4)
+        sw $14, 14 * 4($4)
+        sw $15, 15 * 4($4)
+
+        sw $16, 16 * 4($4)
+        sw $17, 17 * 4($4)
+        sw $18, 18 * 4($4)
+        sw $19, 19 * 4($4)
+        sw $20, 20 * 4($4)
+        sw $21, 21 * 4($4)
+        sw $22, 22 * 4($4)
+        sw $23, 23 * 4($4)
+
+        sw $24, 24 * 4($4)
+        sw $25, 25 * 4($4)
+        sw $26, 26 * 4($4)
+        sw $27, 27 * 4($4)
+        sw $28, 28 * 4($4)
+        sw $29, 29 * 4($4)
+        sw $30, 30 * 4($4)
+        sw $31, 31 * 4($4)
+
+        lw $1, 1 * 4($5)
+        lw $2, 2 * 4($5)
+        lw $3, 3 * 4($5)
+        lw $4, 4 * 4($5)
+        lw $6, 6 * 4($5)
+        lw $7, 7 * 4($5)
+
+        lw $8, 8 * 4($5)
+        lw $9, 9 * 4($5)
+        lw $10, 10 * 4($5)
+        lw $11, 11 * 4($5)
+        lw $12, 12 * 4($5)
+        lw $13, 13 * 4($5)
+        lw $14, 14 * 4($5)
+        lw $15, 15 * 4($5)
+
+        lw $16, 16 * 4($5)
+        lw $17, 17 * 4($5)
+        lw $18, 18 * 4($5)
+        lw $19, 19 * 4($5)
+        lw $20, 20 * 4($5)
+        lw $21, 21 * 4($5)
+        lw $22, 22 * 4($5)
+        lw $23, 23 * 4($5)
+
+        lw $24, 24 * 4($5)
+        lw $25, 25 * 4($5)
+        lw $26, 26 * 4($5)
+        lw $27, 27 * 4($5)
+        lw $28, 28 * 4($5)
+        lw $29, 29 * 4($5)
+        lw $30, 30 * 4($5)
+        lw $31, 31 * 4($5)
+
+        lw $5, 5 * 4($5)
+
+        jr $31
+        nop
+.end rust_swap_registers
diff --git a/src/rt/arch/mipsel/morestack.S b/src/rt/arch/mipsel/morestack.S
new file mode 100644
index 00000000000..266933df8c5
--- /dev/null
+++ b/src/rt/arch/mipsel/morestack.S
@@ -0,0 +1,43 @@
+// Mark stack as non-executable
+#if defined(__linux__) && defined(__ELF__)
+.section        .note.GNU-stack, "", @progbits
+#endif
+
+/* See i386/morestack.S for the lengthy, general explanation. */
+
+.text
+
+.globl rust_stack_exhausted
+.globl __morestack
+
+.hidden __morestack
+
+.cfi_startproc
+.set nomips16
+.ent __morestack
+__morestack:
+        .set noreorder
+        .set nomacro
+
+        addiu $29, $29, -4
+        sw $30, 0($29)
+
+        // 16 = 4 (current) + 12 (previous)
+        .cfi_def_cfa_offset 16
+        .cfi_offset 31, -4
+        .cfi_offset 30, -16
+
+        move $30, $29
+        .cfi_def_cfa_register 30
+
+        // O32 ABI always reserves 16 bytes for arguments
+        addiu $29, $29, -16
+
+        lw $25, %call16(rust_stack_exhausted)($28)
+        jalr $25
+        nop
+
+        // the above function make sure that we never get here
+
+.end __morestack
+.cfi_endproc
diff --git a/src/rt/arch/mipsel/record_sp.S b/src/rt/arch/mipsel/record_sp.S
new file mode 100644
index 00000000000..a6dfa04edbb
--- /dev/null
+++ b/src/rt/arch/mipsel/record_sp.S
@@ -0,0 +1,40 @@
+// Mark stack as non-executable
+#if defined(__linux__) && defined(__ELF__)
+.section	.note.GNU-stack, "", @progbits
+#endif
+
+.text
+
+.globl record_sp_limit
+.align 2
+.set nomips16
+.ent record_sp_limit
+record_sp_limit:
+        .set noreorder
+        .set nomacro
+        .set push
+        .set mips32r2
+        rdhwr $3, $29
+        .set pop
+        addiu $3, $3, -0x7004
+        sw $4, 0($3)
+        jr $31
+        nop
+.end record_sp_limit
+
+.globl get_sp_limit
+.align 2
+.set nomips16
+.ent get_sp_limit
+get_sp_limit:
+        .set noreorder
+        .set nomacro
+        .set push
+        .set mips32r2
+        rdhwr $3, $29
+        .set pop
+        addiu $3, $3, -0x7004
+        lw $2, 0($3)
+        jr $31
+        nop
+.end get_sp_limit