X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb/blobdiff_plain/4bc8424a9fde81305a5bcd04708492f3a067b438..6ae7b8549252175fdf8749aed634bd48d3232532:/base/asm-common.h

diff --git a/base/asm-common.h b/base/asm-common.h
index e8f6445c..83aac636 100644
--- a/base/asm-common.h
+++ b/base/asm-common.h
@@ -106,12 +106,14 @@ name:
 
 #if __ELF__
 
+// Special arrangements for position-independent code.
 #if __PIC__ || __PIE__
 #  define WANT_PIC 1
 #endif
 
+// Additional symbol metadata.
 #define TYPE_FUNC(name) .type name, STT_FUNC
-
+#define TYPE_OBJ(name) .type name, STT_OBJECT
 #define SIZE_OBJ(name) .size name, . - name
 
 #endif
@@ -121,6 +123,7 @@ name:
 
 #if ABI_WIN
 
+// Function names need decorating on 32-bit i386.
 #if CPUFAM_X86
 #  define F(name) _##name
 #endif
@@ -311,6 +314,7 @@ name:
 // R_r(decor) applies decoration decor to register r, which is an internal
 // register name.  The internal register names are: `ip', `a', `b', `c', `d',
 // `si', `di', `bp', `sp', `r8'--`r15'.
+#define R_nil(decor) nil
 #define R_ip(decor) _DECOR(ip, decor, ip)
 #define R_a(decor) _DECOR(abcd, decor, a)
 #define R_b(decor) _DECOR(abcd, decor, b)
@@ -345,6 +349,8 @@ name:
 // assembler-level register name, in place of any decoration that register
 // name has already.
 
+#define _REGFORM_nil(decor) R_nil(decor)
+
 #define _REGFORM_ip(decor) R_ip(decor)
 #define _REGFORM_eip(decor) R_ip(decor)
 
@@ -452,10 +458,20 @@ name:
 #endif
 #define WHOLE(reg) _REGFORM(reg, r)
 
+// Macros for some common registers.
+#define AX R_a(r)
+#define BX R_b(r)
+#define CX R_c(r)
+#define DX R_d(r)
+#define SI R_si(r)
+#define DI R_di(r)
+#define BP R_bp(r)
+#define SP R_sp(r)
+
 // Stack management and unwinding.
-.macro	setfp	fp=R_bp(r), offset=0
+.macro	setfp	fp=BP, offset=0
   .if \offset == 0
-	mov	\fp, R_sp(r)
+	mov	\fp, SP
 #if __ELF__
 	  .cfi_def_cfa_register \fp
 #endif
@@ -463,7 +479,7 @@ name:
 	  .seh_setframe \fp, 0
 #endif
   .else
-	lea	\fp, [R_sp(r) + \offset]
+	lea	\fp, [SP + \offset]
 #if __ELF__
 	  .cfi_def_cfa_register \fp
 	  .cfi_adjust_cfa_offset -\offset
@@ -478,14 +494,14 @@ name:
 
 .macro	_dropfp	fp, offset=0
   .if \offset == 0
-	mov	R_sp(r), \fp
+	mov	SP, \fp
 #if __ELF__
-	  .cfi_def_cfa_register R_sp(r)
+	  .cfi_def_cfa_register SP
 #endif
   .else
-	lea	R_sp(r), [\fp - \offset]
+	lea	SP, [\fp - \offset]
 #if __ELF__
-	  .cfi_def_cfa_register R_sp(r)
+	  .cfi_def_cfa_register SP
 	  .cfi_adjust_cfa_offset +\offset
 #endif
   .endif
@@ -494,7 +510,7 @@ name:
 .endm
 
 .macro	stalloc	n
-	sub	R_sp(r), \n
+	sub	SP, \n
 #if __ELF__
 	  .cfi_adjust_cfa_offset +\n
 #endif
@@ -504,7 +520,7 @@ name:
 .endm
 
 .macro	stfree	n
-	add	R_sp(r), \n
+	add	SP, \n
 #if __ELF__
 	  .cfi_adjust_cfa_offset -\n
 #endif
@@ -530,14 +546,14 @@ name:
 .endm
 
 .macro	savexmm	r, offset
-	movdqa	[R_sp(r) + \offset], \r
+	movdqa	[SP + \offset], \r
 #if ABI_WIN && CPUFAM_AMD64
 	  .seh_savexmm \r, \offset
 #endif
 .endm
 
 .macro	rstrxmm	r, offset
-	movdqa	\r, [R_sp(r) + \offset]
+	movdqa	\r, [SP + \offset]
 .endm
 
 .macro	endprologue
@@ -657,6 +673,8 @@ name:
 // Internal macros: `_REGFORM_r(decor)' applies decoration decor to register
 // name r.
 
+#define _REGFORM_nil(decor) nil
+
 #define _REGFORM_s0(decor) _DECOR(s, decor, 0)
 #define _REGFORM_s1(decor) _DECOR(s, decor, 1)
 #define _REGFORM_s2(decor) _DECOR(s, decor, 2)
@@ -1099,6 +1117,59 @@ name:
 .macro	endprologue
 .endm
 
+// cmov RD, RN, CC: set RD to RN if CC is satisfied, otherwise do nothing
+.macro	cmov	rd, rn, cc
+	csel	\rd, \rn, \rd, \cc
+.endm
+
+// Notational improvement: write `csel.CC' etc., rather than `csel ..., CC'.
+#define _COND(_)							\
+	_(eq) _(ne) _(cs) _(cc) _(vs) _(vc) _(mi) _(pl)			\
+	_(ge) _(lt) _(gt) _(le) _(hi) _(ls) _(al) _(nv)			\
+	_(hs) _(lo)
+#define _INST(_)							\
+	_(ccmp) _(ccmn)							\
+	_(csel) _(cmov)							\
+	_(csinc) _(cinc) _(cset)					\
+	_(csneg) _(cneg)						\
+	_(csinv) _(cinv) _(csetm)
+#define _CONDVAR(cc) _definstvar cc;
+#define _INSTVARS(inst)							\
+	.macro _definstvar cc;						\
+	  .macro inst.\cc args:vararg; inst \args, \cc; .endm;		\
+	.endm;								\
+	_COND(_CONDVAR);						\
+	.purgem _definstvar;
+	_INST(_INSTVARS)
+#undef _COND
+#undef _INST
+#undef _CONDVAR
+#undef _INSTVARS
+
+// Flag bits for `ccmp' and friends.
+#define CCMP_N 8
+#define CCMP_Z 4
+#define CCMP_C 2
+#define CCMP_V 1
+
+// Flag settings for satisfying conditions.
+#define CCMP_MI CCMP_N
+#define CCMP_PL 0
+#define CCMP_EQ CCMP_Z
+#define CCMP_NE 0
+#define CCMP_CS CCMP_C
+#define CCMP_HS CCMP_C
+#define CCMP_CC 0
+#define CCMP_LO 0
+#define CCMP_VS CCMP_V
+#define CCMP_VC 0
+#define CCMP_HI CCMP_C
+#define CCMP_LS 0
+#define CCMP_LT CCMP_N
+#define CCMP_GE 0
+#define CCMP_LE CCMP_N
+#define CCMP_GT 0
+
 #endif
 
 ///--------------------------------------------------------------------------
@@ -1116,18 +1187,24 @@ name:
 #endif
 
 #ifndef F
-#  define F(name) name
+#  ifdef SYM_USCORE
+#    define F(name) _##name
+#  else
+#    define F(name) name
+#  endif
 #endif
 
 #ifndef TYPE_FUNC
 #  define TYPE_FUNC(name)
 #endif
-
+#ifndef TYPE_OBJ
+#  define TYPE_OBJ(name)
+#endif
 #ifndef SIZE_OBJ
 #  define SIZE_OBJ(name)
 #endif
 
-#if __ELF__ && !defined(WANT_EXECUTABLE_STACK)
+#if __ELF__ && !defined(FORCE_EXECUTABLE_STACK)
 	.pushsection .note.GNU-stack, "", _SECTTY(progbits)
 	.popsection
 #endif