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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/blackfin/lib/modsi3.S
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+/*
+ * This program computes 32 bit signed remainder. It calls div32 function
+ * for quotient estimation.
+ * Registers in: R0, R1 = Numerator/ Denominator
+ * Registers out: R0 = Remainder
+ *
+ * Copyright 2004-2009 Analog Devices Inc.
+ *
+ * Licensed under the Clear BSD license or the GPL-2 (or later)
+ */
+
+.global ___modsi3;
+.type ___modsi3, STT_FUNC;
+.extern ___divsi3;
+.type ___divsi3, STT_FUNC;
+
+#ifdef CONFIG_ARITHMETIC_OPS_L1
+.section .l1.text
+#else
+.text
+#endif
+
+___modsi3:
+
+ CC=R0==0;
+ IF CC JUMP .LRETURN_R0; /* Return 0, if numerator == 0 */
+ CC=R1==0;
+ IF CC JUMP .LRETURN_ZERO; /* Return 0, if denominator == 0 */
+ CC=R0==R1;
+ IF CC JUMP .LRETURN_ZERO; /* Return 0, if numerator == denominator */
+ CC = R1 == 1;
+ IF CC JUMP .LRETURN_ZERO; /* Return 0, if denominator == 1 */
+ CC = R1 == -1;
+ IF CC JUMP .LRETURN_ZERO; /* Return 0, if denominator == -1 */
+
+ /* Valid input. Use __divsi3() to compute the quotient, and then
+ * derive the remainder from that. */
+
+ [--SP] = (R7:6); /* Push R7 and R6 */
+ [--SP] = RETS; /* and return address */
+ R7 = R0; /* Copy of R0 */
+ R6 = R1; /* Save for later */
+ SP += -12; /* Should always provide this space */
+ CALL ___divsi3; /* Compute signed quotient using ___divsi3()*/
+ SP += 12;
+ R0 *= R6; /* Quotient * divisor */
+ R0 = R7 - R0; /* Dividend - (quotient * divisor) */
+ RETS = [SP++]; /* Get back return address */
+ (R7:6) = [SP++]; /* Pop registers R7 and R4 */
+ RTS; /* Store remainder */
+
+.LRETURN_ZERO:
+ R0 = 0;
+.LRETURN_R0:
+ RTS;
+
+.size ___modsi3, .-___modsi3