Bug 1323642 - IonMonkey: MIPS64: Fix load unsigned 48-bit immediate

Issue:
In ma_li(Register, ImmWord):
	Load unsigned 48-bit immediate: 0x0000_8000_0000_0000
	Wrong instructions stream:
		lui	reg, 0x8000
		dsll	reg, reg, 16 # reg = 0xffff_8000_0000_0000
	Fixed instructions stream:
		lui	reg, 0x8000
		dinsu	reg, zero, 32, 32
		dsll	reg, reg, 16

Tag: #1542

1 files changed, 32 insertions, 23 deletions

diff --git a/js/src/jit/mips64/MacroAssembler-mips64.cpp b/js/src/jit/mips64/MacroAssembler-mips64.cpp
index f58184bca..7021d0f74 100644
--- a/js/src/jit/mips64/MacroAssembler-mips64.cpp
+++ b/js/src/jit/mips64/MacroAssembler-mips64.cpp
@@ -258,36 +258,45 @@ MacroAssemblerMIPS64::ma_li(Register dest, ImmWord imm)
 {
     int64_t value = imm.value;
 
-    if (value >= INT16_MIN && value <= INT16_MAX) {
+    if (-1 == (value >> 15) || 0 == (value >> 15)) {
         as_addiu(dest, zero, value);
-    } else if (imm.value <= UINT16_MAX) {
-        as_ori(dest, zero, Imm16::Lower(Imm32(value)).encode());
-    } else if (value >= INT32_MIN && value <= INT32_MAX) {
-        as_lui(dest, Imm16::Upper(Imm32(value)).encode());
-        if (value & 0xffff)
-            as_ori(dest, dest, Imm16::Lower(Imm32(value)).encode());
-    } else if (imm.value <= UINT32_MAX) {
-        as_lui(dest, Imm16::Upper(Imm32(value)).encode());
-        if (value & 0xffff)
-            as_ori(dest, dest, Imm16::Lower(Imm32(value)).encode());
+        return;
+    }
+    if (0 == (value >> 16)) {
+        as_ori(dest, zero, value);
+        return;
+    }
+
+    if (-1 == (value >> 31) || 0 == (value >> 31)) {
+        as_lui(dest, uint16_t(value >> 16));
+    } else if (0 == (value >> 32)) {
+        as_lui(dest, uint16_t(value >> 16));
         as_dinsu(dest, zero, 32, 32);
+    } else if (-1 == (value >> 47) || 0 == (value >> 47)) {
+        as_lui(dest, uint16_t(value >> 32));
+        if (uint16_t(value >> 16))
+            as_ori(dest, dest, uint16_t(value >> 16));
+        as_dsll(dest, dest, 16);
+    } else if (0 == (value >> 48)) {
+        as_lui(dest, uint16_t(value >> 32));
+        as_dinsu(dest, zero, 32, 32);
+        if (uint16_t(value >> 16))
+            as_ori(dest, dest, uint16_t(value >> 16));
+        as_dsll(dest, dest, 16);
     } else {
-        uint64_t high = imm.value >> 32;
-
-        if (imm.value >> 48) {
-            as_lui(dest, Imm16::Upper(Imm32(high)).encode());
-            if (high & 0xffff)
-                as_ori(dest, dest, Imm16::Lower(Imm32(high)).encode());
+        as_lui(dest, uint16_t(value >> 48));
+        if (uint16_t(value >> 32))
+            as_ori(dest, dest, uint16_t(value >> 32));
+        if (uint16_t(value >> 16)) {
+            as_dsll(dest, dest, 16);
+            as_ori(dest, dest, uint16_t(value >> 16));
             as_dsll(dest, dest, 16);
         } else {
-            as_lui(dest, Imm16::Lower(Imm32(high)).encode());
+            as_dsll32(dest, dest, 32);
         }
-        if ((imm.value >> 16) & 0xffff)
-            as_ori(dest, dest, Imm16::Upper(Imm32(value)).encode());
-        as_dsll(dest, dest, 16);
-        if (value & 0xffff)
-            as_ori(dest, dest, Imm16::Lower(Imm32(value)).encode());
     }
+    if (uint16_t(value))
+        as_ori(dest, dest, uint16_t(value));
 }
 
 // This method generates lui, dsll and ori instruction block that can be modified