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+# Assembler initialization code for actual execution test.
+
+# This code becomes the start of the execution test program. It is
+# responsible for initializing the static data, invoking the C code,
+# and returning the result. It is called as though it were a C
+# function with an argument of the address of the data segment.
+
+# We need to know the value of _ftext and _fdata at link time, but we
+# have no way to actually get that at runtime. This is because when
+# this code is compiled with -membedded-pic, the la instruction will
+# be turned into an addiu $gp instruction. We work around this by
+# storing the information in words in the .data section. We then load
+# the values of these words *before* doing the runtime relocation.
+ .sdata
+text_start:
+ .word _ftext
+data_start:
+ .word _fdata
+
+ .globl start
+ .text
+start:
+ # Grab some space on the stack, just as though we were a real
+ # function.
+ addiu $sp,$sp,-8
+ sw $31,0($sp)
+
+ # Save the $gp register, and set it up for our data section.
+ sw $gp,4($sp)
+
+ addu $gp,$4,0x8000 # macro
+
+ # The start of the data segment is in $4.
+
+ # Get the address of start into $5 in a position independent
+ # fashion.
+ .set noreorder
+ $LF1 = . + 8
+ bal $LF1
+ la $5,start-$LF1 # macro
+ .set reorder
+ addu $5,$5,$31
+
+ # Now get the address of _ftext into $6.
+ la $6,_ftext-start # macro
+ addu $6,$6,$5
+
+ # Get the value of _ftext used to link into $7.
+ lw $7,text_start # macro
+
+ # Get the value of _fdata used to link into $8.
+ lw $8,data_start # macro
+
+ # Get the address of __runtime_reloc_start into $9.
+ la $9,__runtime_reloc_start-start # macro
+ addu $9,$9,$5
+
+ # Get the address of __runtime_reloc_stop into $10.
+ la $10,__runtime_reloc_stop-start # macro
+ addu $10,$10,$5
+
+ # The words between $9 and $10 are the runtime initialization
+ # instructions. Step through and relocate them. First set
+ # $11 and $12 to the values to add to text and data sections,
+ # respectively.
+ subu $11,$6,$7
+ subu $12,$4,$8
+
+1:
+ bge $9,$10,3f # macro
+ lw $13,0($9)
+ and $14,$13,0xfffffffe # macro
+ move $15,$11
+ beq $13,$14,2f
+ move $15,$12
+2:
+ addu $14,$14,$4
+ lw $24,0($14)
+ addu $24,$24,$15
+ sw $24,0($14)
+ addiu $9,$9,4
+ b 1b
+3:
+
+ # Now the statically initialized data has been relocated
+ # correctly, and we can call the C code which does the actual
+ # testing.
+ bal foo
+
+ # We return the value returned by the C code.
+ lw $31,0($sp)
+ lw $gp,4($sp)
+ addu $sp,$sp,8
+ j $31