From: Taylor R Campbell <campbell@mumble.net>
Date: Thu, 7 Oct 2010 05:59:36 +0000 (+0000)
Subject: Fix comments in i386.m4 and x86-64.m4 about executable stack.
X-Git-Tag: 20101212-Gtk~49
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=1c7865d7bb203128dfaa53b3fabe816f5be7e8b8;p=mit-scheme.git

Fix comments in i386.m4 and x86-64.m4 about executable stack.
---

diff --git a/src/microcode/cmpauxmd/i386.m4 b/src/microcode/cmpauxmd/i386.m4
index a69527e18..7f3165c03 100644
--- a/src/microcode/cmpauxmd/i386.m4
+++ b/src/microcode/cmpauxmd/i386.m4
@@ -1207,35 +1207,56 @@ asm_fixnum_rsh_overflow_negative:
 	OP(mov,l)	TW(IMM_DETAGGED_FIXNUM_MINUS_ONE,REG(eax))
 	ret
 
-define_c_label(i387_read_fp_control_word)
-IF387(`	OP(cmp,l)	TW(IMM(0),ABS(EVR(i387_presence)))
-	je		i387_read_fp_control_word_lose
-	enter		IMM(4),IMM(0)
+define_c_label(sse_read_mxcsr)
+IFSSE(`	enter		IMM(4),IMM(0)
+	stmxcsr		IND(REG(esp))
+	OP(mov,l)	TW(IND(REG(esp)),REG(eax))
+	leave')
+	ret
+
+define_c_label(sse_write_mxcsr)
+IFSSE(`	ldmxcsr		LOF(4,REG(esp))')
+	ret
+
+define_c_label(x87_clear_exceptions)
+IF387(`	fnclex')
+	ret
+
+define_c_label(x87_trap_exceptions)
+IF387(`	fwait')
+	ret
+
+define_c_label(x87_read_control_word)
+IF387(`	enter		IMM(4),IMM(0)
 	fnstcw		IND(REG(esp))
 	OP(mov,w)	TW(IND(REG(esp)),REG(ax))
-	leave
+	leave')
 	ret
-')
 
-i387_read_fp_control_word_lose:
-	OP(xor,l)	TW(REG(eax),REG(eax))
+define_c_label(x87_write_control_word)
+IF387(`	fldcw		LOF(4,REG(esp))')
 	ret
 
-define_c_label(i387_write_fp_control_word)
-IF387(`	OP(cmp,l)	TW(IMM(0),ABS(EVR(i387_presence)))
-	je		i387_write_fp_control_word_lose
-	fldcw		LOF(4,REG(esp))
+define_c_label(x87_read_status_word)
+IF387(`	enter		IMM(4),IMM(0)
+	fnstsw		IND(REG(esp))
+	OP(mov,w)	TW(IND(REG(esp)),REG(ax))
+	leave')
+	ret
+
+define_c_label(x87_read_environment)
+IF387(`	OP(mov,l)	TW(LOF(4,REG(esp)),REG(eax))
+	fnstenv		IND(REG(eax))')
 	ret
-')
 
-i387_write_fp_control_word_lose:
+define_c_label(x87_write_environment)
+IF387(`	OP(mov,l)	TW(LOF(4,REG(esp)),REG(eax))
+	fldenv		IND(REG(eax))')
 	ret
 
 IFDASM(`end')
 
-# Mark the stack nonexecutable.  If we ever put code (e.g.,
-# dynamic-extent closure entry points) on the stack, this would have
-# to change.
+# Mark the C stack nonexecutable.
 
 ifdef(`__linux__', `ifdef(`__ELF__', `.section .note.GNU-stack,"",%progbits')')
 
diff --git a/src/microcode/cmpauxmd/x86-64.m4 b/src/microcode/cmpauxmd/x86-64.m4
index ff2238c57..b70f0c6d5 100644
--- a/src/microcode/cmpauxmd/x86-64.m4
+++ b/src/microcode/cmpauxmd/x86-64.m4
@@ -982,9 +982,7 @@ define_c_label(x86_64_write_mxcsr)
 
 IFDASM(`end')
 
-# Mark the stack nonexecutable.  If we ever put code (e.g.,
-# dynamic-extent closure entry points) on the stack, this would have
-# to change.
+# Mark the C stack nonexecutable.
 
 ifdef(`__linux__', `ifdef(`__ELF__', `.section .note.GNU-stack,"",%progbits')')