From 3df9102c233d3df770450b9eabf91878bf804fe7 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Thu, 19 Oct 2023 10:45:27 +0100
Subject: [PATCH] add fixedloadshift.mdwn which is a copy of fixedload.mdwn not
 edited for descriptions or pseudocode yet.
 https://bugs.libre-soc.org/show_bug.cgi?id=1090

---
 openpower/isa/fixedloadshift.mdwn | 280 ++++++++++++++++++++++++++++++
 1 file changed, 280 insertions(+)
 create mode 100644 openpower/isa/fixedloadshift.mdwn

diff --git a/openpower/isa/fixedloadshift.mdwn b/openpower/isa/fixedloadshift.mdwn
new file mode 100644
index 00000000..75be291a
--- /dev/null
+++ b/openpower/isa/fixedloadshift.mdwn
@@ -0,0 +1,280 @@
+<!-- This defines instructions described in PowerISA Version 3.0 B Book 1 -->
+
+<!-- This defines instructions that load from RAM to a register -->
+
+<!-- Note that these pages also define equivalent store instructions, -->
+<!-- these are described in fixedstore.mdwn -->
+
+<!-- Section 3.3.2 This defines the Fixed-Point Load Instructions pages 47 - 53 -->
+<!-- Section 3.3.3 Fixed-Point Store Instructions pages 54 - 56 -->
+<!-- Section 3.3.3.1 64-bit Fixed-Point Store Instructions pages 57 -->
+<!-- Section 3.3.4 Fixed Point Load and Store Quadword Instructions pages 58 - 59 -->
+<!-- Section 3.3.5 Fixed-Point Load and Store with Byte Reversal Instructions page 60 -->
+<!-- Section 3.3.5.1 64-Bit Load and Store with Byte Reversal Instructions page 61 -->
+<!-- Section 3.3.6 Fixed-Point Load and Store Multiple Instructions page 62 -->
+
+
+
+<!-- Section 3.3.2 This defines the Fixed-Point Load Instructions pages 47 - 53 -->
+
+<!-- The byte, halfword, word, or doubleword in storage addressed by EA is loaded -->
+<!-- into register RT. -->
+
+<!-- Many of the Load instructions have an “update” form, in which register RA is -->
+<!-- updated with the effective address. For these forms, if RA!=0 and RA!=RT, the -->
+<!-- effective address is placed into register RA and the storage element (byte, -->
+<!-- halfword, word, or doubleword) addressed by EA is loaded into RT. -->
+
+
+# Load Byte and Zero Indexed
+
+X-Form
+
+* lbzx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    RT <- ([0] * (XLEN-8)) || MEM(EA, 1)
+
+Special Registers Altered:
+
+    None
+
+# Load Byte and Zero with Update Indexed
+
+X-Form
+
+* lbzux RT,RA,RB
+
+Pseudo-code:
+
+    EA <- (RA) + (RB)
+    RT <- ([0] * (XLEN-8)) || MEM(EA, 1)
+    RA <- EA
+
+Special Registers Altered:
+
+    None
+
+# Load Halfword and Zero Indexed
+
+X-Form
+
+* lhzx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    RT <- ([0] * (XLEN-16)) || MEM(EA, 2)
+
+Special Registers Altered:
+
+    None
+
+# Load Halfword and Zero with Update Indexed
+
+X-Form
+
+* lhzux RT,RA,RB
+
+Pseudo-code:
+
+    EA <- (RA) + (RB)
+    RT <- ([0] * (XLEN-16)) || MEM(EA, 2)
+    RA <- EA
+
+Special Registers Altered:
+
+    None
+
+# Load Halfword Algebraic Indexed
+
+X-Form
+
+* lhax RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    RT <- EXTS(MEM(EA, 2))
+
+Special Registers Altered:
+
+    None
+
+# Load Halfword Algebraic with Update Indexed
+
+X-Form
+
+* lhaux RT,RA,RB
+
+Pseudo-code:
+
+    EA <- (RA) + (RB)
+    RT <- EXTS(MEM(EA, 2))
+    RA <- EA
+
+Special Registers Altered:
+
+    None
+
+# Load Word and Zero Indexed
+
+X-Form
+
+* lwzx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    RT <- [0] * 32 || MEM(EA, 4)
+
+Special Registers Altered:
+
+    None
+
+# Load Word and Zero with Update Indexed
+
+X-Form
+
+* lwzux RT,RA,RB
+
+Pseudo-code:
+
+    EA <- (RA) + (RB)
+    RT <- [0] * 32 || MEM(EA, 4)
+    RA <- EA
+
+Special Registers Altered:
+
+    None
+
+# Load Word Algebraic Indexed
+
+X-Form
+
+* lwax RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    RT <- EXTS(MEM(EA, 4))
+
+Special Registers Altered:
+
+    None
+
+# Load Word Algebraic with Update Indexed
+
+X-Form
+
+* lwaux RT,RA,RB
+
+Pseudo-code:
+
+    EA <- (RA) + (RB)
+    RT <- EXTS(MEM(EA, 4))
+    RA <- EA
+
+Special Registers Altered:
+
+    None
+
+# Load Doubleword Indexed
+
+X-Form
+
+* ldx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    RT <- MEM(EA, 8)
+
+Special Registers Altered:
+
+    None
+
+# Load Doubleword with Update Indexed
+
+X-Form
+
+* ldux RT,RA,RB
+
+Pseudo-code:
+
+    EA <- (RA) + (RB)
+    RT <- MEM(EA, 8)
+    RA <- EA
+
+Special Registers Altered:
+
+    None
+
+<!-- byte-reverse shifted -->
+
+# Load Halfword Byte-Reverse Indexed
+
+X-Form
+
+* lhbrx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    load_data <- MEM(EA, 2)
+    RT <- [0]*48 || load_data[8:15] || load_data[0:7]
+
+Special Registers Altered:
+
+    None
+
+# Load Word Byte-Reverse Indexed
+
+X-Form
+
+* lwbrx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    load_data <- MEM(EA, 4)
+    RT <- ([0] * 32 || load_data[24:31] || load_data[16:23]
+                    || load_data[8:15]  || load_data[0:7])
+
+Special Registers Altered:
+
+    None
+
+
+<!-- Section 3.3.5.1 64-Bit Load and Store with Byte Reversal Instructions page 61 -->
+
+# Load Doubleword Byte-Reverse Indexed
+
+X-Form
+
+* ldbrx RT,RA,RB
+
+Pseudo-code:
+
+    b <- (RA|0)
+    EA <- b + (RB)
+    load_data <- MEM(EA, 8)
+    RT <- (load_data[56:63] || load_data[48:55]
+        || load_data[40:47] || load_data[32:39]
+        || load_data[24:31] || load_data[16:23]
+        || load_data[8:15]  || load_data[0:7])
+
+Special Registers Altered:
+
+    None
+
-- 
2.30.2